Exemplo n.º 1
0
/*
 * To draw a wide line we can simply redraw the span N times, side by side.
 */
static void
draw_wide_line( GLcontext *ctx, SWspan *span, GLboolean xMajor )
{
   const GLint width = (GLint) CLAMP(ctx->Line.Width,
                                     ctx->Const.MinLineWidth,
                                     ctx->Const.MaxLineWidth);
   GLint start;

   ASSERT(span->end < MAX_WIDTH);

   if (width & 1)
      start = width / 2;
   else
      start = width / 2 - 1;

   if (xMajor) {
      GLint *y = span->array->y;
      GLuint i;
      GLint w;
      for (w = 0; w < width; w++) {
         if (w == 0) {
            for (i = 0; i < span->end; i++)
               y[i] -= start;
         }
         else {
            for (i = 0; i < span->end; i++)
               y[i]++;
         }
         if (ctx->Visual.rgbMode)
            _swrast_write_rgba_span(ctx, span);
         else
            _swrast_write_index_span(ctx, span);
      }
   }
   else {
      GLint *x = span->array->x;
      GLuint i;
      GLint w;
      for (w = 0; w < width; w++) {
         if (w == 0) {
            for (i = 0; i < span->end; i++)
               x[i] -= start;
         }
         else {
            for (i = 0; i < span->end; i++)
               x[i]++;
         }
         if (ctx->Visual.rgbMode)
            _swrast_write_rgba_span(ctx, span);
         else
            _swrast_write_index_span(ctx, span);
      }
   }
}
Exemplo n.º 2
0
/*
 * To draw a wide line we can simply redraw the span N times, side by side.
 */
static void
draw_wide_line( struct gl_context *ctx, SWspan *span, GLboolean xMajor )
{
   const GLint width = (GLint) CLAMP(ctx->Line.Width,
                                     ctx->Const.MinLineWidth,
                                     ctx->Const.MaxLineWidth);
   GLint start;

   assert(span->end < SWRAST_MAX_WIDTH);

   if (width & 1)
      start = width / 2;
   else
      start = width / 2 - 1;

   if (xMajor) {
      GLint *y = span->array->y;
      GLuint i;
      GLint w;
      for (w = 0; w < width; w++) {
         if (w == 0) {
            for (i = 0; i < span->end; i++)
               y[i] -= start;
         }
         else {
            for (i = 0; i < span->end; i++)
               y[i]++;
         }
	 _swrast_write_rgba_span(ctx, span);
      }
   }
   else {
      GLint *x = span->array->x;
      GLuint i;
      GLint w;
      for (w = 0; w < width; w++) {
         if (w == 0) {
            for (i = 0; i < span->end; i++)
               x[i] -= start;
         }
         else {
            for (i = 0; i < span->end; i++)
               x[i]++;
         }
	 _swrast_write_rgba_span(ctx, span);
      }
   }
}
Exemplo n.º 3
0
/**
 * Draw size=1, single-pixel point
 */
static void
pixel_point(struct gl_context *ctx, const SWvertex *vert)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   /*
    * Note that unlike the other functions, we put single-pixel points
    * into a special span array in order to render as many points as
    * possible with a single _swrast_write_rgba_span() call.
    */
   SWspan *span = &(swrast->PointSpan);
   GLuint count;

   CULL_INVALID(vert);

   /* Span init */
   span->interpMask = 0;
   span->arrayMask = SPAN_XY | SPAN_Z;
   span->arrayMask |= SPAN_RGBA;
   /*span->arrayMask |= SPAN_LAMBDA;*/
   span->arrayAttribs = swrast->_ActiveAttribMask; /* we'll produce these vals */

   /* need these for fragment programs */
   span->attrStart[FRAG_ATTRIB_WPOS][3] = 1.0F;
   span->attrStepX[FRAG_ATTRIB_WPOS][3] = 0.0F;
   span->attrStepY[FRAG_ATTRIB_WPOS][3] = 0.0F;

   /* check if we need to flush */
   if (span->end >= MAX_WIDTH ||
       (swrast->_RasterMask & (BLEND_BIT | LOGIC_OP_BIT | MASKING_BIT)) ||
       span->facing != swrast->PointLineFacing) {
      if (span->end > 0) {
	 _swrast_write_rgba_span(ctx, span);
         span->end = 0;
      }
   }

   count = span->end;

   span->facing = swrast->PointLineFacing;

   /* fragment attributes */
   span->array->rgba[count][RCOMP] = vert->color[0];
   span->array->rgba[count][GCOMP] = vert->color[1];
   span->array->rgba[count][BCOMP] = vert->color[2];
   span->array->rgba[count][ACOMP] = vert->color[3];

   ATTRIB_LOOP_BEGIN
      COPY_4V(span->array->attribs[attr][count], vert->attrib[attr]);
   ATTRIB_LOOP_END

   /* fragment position */
   span->array->x[count] = (GLint) vert->attrib[FRAG_ATTRIB_WPOS][0];
   span->array->y[count] = (GLint) vert->attrib[FRAG_ATTRIB_WPOS][1];
   span->array->z[count] = (GLint) (vert->attrib[FRAG_ATTRIB_WPOS][2] + 0.5F);

   span->end = count + 1;
   ASSERT(span->end <= MAX_WIDTH);
}
Exemplo n.º 4
0
void
_swrast_flush( struct gl_context *ctx )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   /* flush any pending fragments from rendering points */
   if (swrast->PointSpan.end > 0) {
      _swrast_write_rgba_span(ctx, &(swrast->PointSpan));
      swrast->PointSpan.end = 0;
   }
}
Exemplo n.º 5
0
void
_swrast_flush( GLcontext *ctx )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   /* flush any pending fragments from rendering points */
   if (swrast->PointSpan.end > 0) {
      if (ctx->Visual.rgbMode) {
         _swrast_write_rgba_span(ctx, &(swrast->PointSpan));
      }
      else {
         _swrast_write_index_span(ctx, &(swrast->PointSpan));
      }
      swrast->PointSpan.end = 0;
   }
}
Exemplo n.º 6
0
/**
 * Draw a point sprite
 */
static void
sprite_point(GLcontext *ctx, const SWvertex *vert)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   SWspan span;
   GLfloat size;
   GLuint tCoords[MAX_TEXTURE_COORD_UNITS + 1];
   GLuint numTcoords = 0;
   GLfloat t0, dtdy;

   CULL_INVALID(vert);

   /* z coord */
   if (ctx->DrawBuffer->Visual.depthBits <= 16)
      span.z = FloatToFixed(vert->attrib[FRAG_ATTRIB_WPOS][2] + 0.5F);
   else
      span.z = (GLuint) (vert->attrib[FRAG_ATTRIB_WPOS][2] + 0.5F);
   span.zStep = 0;

   size = get_size(ctx, vert, GL_FALSE);

   /* span init */
   INIT_SPAN(span, GL_POINT);
   span.interpMask = SPAN_Z | SPAN_RGBA;

   span.facing = swrast->PointLineFacing;

   span.red   = ChanToFixed(vert->color[0]);
   span.green = ChanToFixed(vert->color[1]);
   span.blue  = ChanToFixed(vert->color[2]);
   span.alpha = ChanToFixed(vert->color[3]);
   span.redStep = 0;
   span.greenStep = 0;
   span.blueStep = 0;
   span.alphaStep = 0;

   /* need these for fragment programs */
   span.attrStart[FRAG_ATTRIB_WPOS][3] = 1.0F;
   span.attrStepX[FRAG_ATTRIB_WPOS][3] = 0.0F;
   span.attrStepY[FRAG_ATTRIB_WPOS][3] = 0.0F;

   {
      GLfloat s, r, dsdx;

      /* texcoord / pointcoord interpolants */
      s = 0.0;
      dsdx = 1.0 / size;
      if (ctx->Point.SpriteOrigin == GL_LOWER_LEFT) {
         dtdy = 1.0 / size;
         t0 = 0.5 * dtdy;
      }
      else {
         /* GL_UPPER_LEFT */
         dtdy = -1.0 / size;
         t0 = 1.0 + 0.5 * dtdy;
      }

      ATTRIB_LOOP_BEGIN
         if (attr >= FRAG_ATTRIB_TEX0 && attr < FRAG_ATTRIB_VAR0) {
            const GLuint u = attr - FRAG_ATTRIB_TEX0;
            /* a texcoord */
            if (ctx->Point.CoordReplace[u]) {
               tCoords[numTcoords++] = attr;

               if (ctx->Point.SpriteRMode == GL_ZERO)
                  r = 0.0F;
               else if (ctx->Point.SpriteRMode == GL_S)
                  r = vert->attrib[attr][0];
               else /* GL_R */
                  r = vert->attrib[attr][2];

               span.attrStart[attr][0] = s;
               span.attrStart[attr][1] = 0.0; /* overwritten below */
               span.attrStart[attr][2] = r;
               span.attrStart[attr][3] = 1.0;

               span.attrStepX[attr][0] = dsdx;
               span.attrStepX[attr][1] = 0.0;
               span.attrStepX[attr][2] = 0.0;
               span.attrStepX[attr][3] = 0.0;

               span.attrStepY[attr][0] = 0.0;
               span.attrStepY[attr][1] = dtdy;
               span.attrStepY[attr][2] = 0.0;
               span.attrStepY[attr][3] = 0.0;

               continue;
            }
         }
         else if (attr == FRAG_ATTRIB_FOGC) {
            /* GLSL gl_PointCoord is stored in fog.zw */
            span.attrStart[FRAG_ATTRIB_FOGC][2] = 0.0;
            span.attrStart[FRAG_ATTRIB_FOGC][3] = 0.0; /* t0 set below */
            span.attrStepX[FRAG_ATTRIB_FOGC][2] = dsdx;
            span.attrStepX[FRAG_ATTRIB_FOGC][3] = 0.0;
            span.attrStepY[FRAG_ATTRIB_FOGC][2] = 0.0;
            span.attrStepY[FRAG_ATTRIB_FOGC][3] = dtdy;
            tCoords[numTcoords++] = FRAG_ATTRIB_FOGC;
            continue;
         }
         /* use vertex's texcoord/attrib */
         COPY_4V(span.attrStart[attr], vert->attrib[attr]);
         ASSIGN_4V(span.attrStepX[attr], 0, 0, 0, 0);
         ASSIGN_4V(span.attrStepY[attr], 0, 0, 0, 0);
      ATTRIB_LOOP_END;
   }

   /* compute pos, bounds and render */
   {
      const GLfloat x = vert->attrib[FRAG_ATTRIB_WPOS][0];
      const GLfloat y = vert->attrib[FRAG_ATTRIB_WPOS][1];
      GLint iSize = (GLint) (size + 0.5F);
      GLint xmin, xmax, ymin, ymax, iy;
      GLint iRadius;
      GLfloat tcoord = t0;

      iSize = MAX2(1, iSize);
      iRadius = iSize / 2;

      if (iSize & 1) {
         /* odd size */
         xmin = (GLint) (x - iRadius);
         xmax = (GLint) (x + iRadius);
         ymin = (GLint) (y - iRadius);
         ymax = (GLint) (y + iRadius);
      }
      else {
         /* even size */
         /* 0.501 factor allows conformance to pass */
         xmin = (GLint) (x + 0.501) - iRadius;
         xmax = xmin + iSize - 1;
         ymin = (GLint) (y + 0.501) - iRadius;
         ymax = ymin + iSize - 1;
      }

      /* render spans */
      for (iy = ymin; iy <= ymax; iy++) {
         GLuint i;
         /* setup texcoord T for this row */
         for (i = 0; i < numTcoords; i++) {
            if (tCoords[i] == FRAG_ATTRIB_FOGC)
               span.attrStart[FRAG_ATTRIB_FOGC][3] = tcoord;
            else
               span.attrStart[tCoords[i]][1] = tcoord;
         }

         /* these might get changed by span clipping */
         span.x = xmin;
         span.y = iy;
         span.end = xmax - xmin + 1;

         _swrast_write_rgba_span(ctx, &span);

         tcoord += dtdy;
      }
   }
}
Exemplo n.º 7
0
/**
 * Draw large (size >= 1) non-AA point.  RGB or CI mode.
 */
static void
large_point(GLcontext *ctx, const SWvertex *vert)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   const GLboolean ciMode = !ctx->Visual.rgbMode;
   SWspan span;
   GLfloat size;

   CULL_INVALID(vert);

   /* z coord */
   if (ctx->DrawBuffer->Visual.depthBits <= 16)
      span.z = FloatToFixed(vert->attrib[FRAG_ATTRIB_WPOS][2] + 0.5F);
   else
      span.z = (GLuint) (vert->attrib[FRAG_ATTRIB_WPOS][2] + 0.5F);
   span.zStep = 0;

   size = get_size(ctx, vert, GL_FALSE);

   /* span init */
   INIT_SPAN(span, GL_POINT);
   span.arrayMask = SPAN_XY;
   span.facing = swrast->PointLineFacing;

   if (ciMode) {
      span.interpMask = SPAN_Z | SPAN_INDEX;
      span.index = FloatToFixed(vert->attrib[FRAG_ATTRIB_CI][0]);
      span.indexStep = 0;
   }
   else {
      span.interpMask = SPAN_Z | SPAN_RGBA;
      span.red   = ChanToFixed(vert->color[0]);
      span.green = ChanToFixed(vert->color[1]);
      span.blue  = ChanToFixed(vert->color[2]);
      span.alpha = ChanToFixed(vert->color[3]);
      span.redStep = 0;
      span.greenStep = 0;
      span.blueStep = 0;
      span.alphaStep = 0;
   }

   /* need these for fragment programs */
   span.attrStart[FRAG_ATTRIB_WPOS][3] = 1.0F;
   span.attrStepX[FRAG_ATTRIB_WPOS][3] = 0.0F;
   span.attrStepY[FRAG_ATTRIB_WPOS][3] = 0.0F;

   ATTRIB_LOOP_BEGIN
      COPY_4V(span.attrStart[attr], vert->attrib[attr]);
      ASSIGN_4V(span.attrStepX[attr], 0, 0, 0, 0);
      ASSIGN_4V(span.attrStepY[attr], 0, 0, 0, 0);
   ATTRIB_LOOP_END

   /* compute pos, bounds and render */
   {
      const GLfloat x = vert->attrib[FRAG_ATTRIB_WPOS][0];
      const GLfloat y = vert->attrib[FRAG_ATTRIB_WPOS][1];
      GLint iSize = (GLint) (size + 0.5F);
      GLint xmin, xmax, ymin, ymax, ix, iy;
      GLint iRadius;

      iSize = MAX2(1, iSize);
      iRadius = iSize / 2;

      if (iSize & 1) {
         /* odd size */
         xmin = (GLint) (x - iRadius);
         xmax = (GLint) (x + iRadius);
         ymin = (GLint) (y - iRadius);
         ymax = (GLint) (y + iRadius);
      }
      else {
         /* even size */
         /* 0.501 factor allows conformance to pass */
         xmin = (GLint) (x + 0.501) - iRadius;
         xmax = xmin + iSize - 1;
         ymin = (GLint) (y + 0.501) - iRadius;
         ymax = ymin + iSize - 1;
      }

      /* generate fragments */
      span.end = 0;
      for (iy = ymin; iy <= ymax; iy++) {
         for (ix = xmin; ix <= xmax; ix++) {
            span.array->x[span.end] = ix;
            span.array->y[span.end] = iy;
            span.end++;
         }
      }
      assert(span.end <= MAX_WIDTH);
      _swrast_write_rgba_span(ctx, &span);
   }
}
Exemplo n.º 8
0
/**
 * Draw smooth/antialiased point.  RGB or CI mode.
 */
static void
smooth_point(GLcontext *ctx, const SWvertex *vert)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   const GLboolean ciMode = !ctx->Visual.rgbMode;
   SWspan span;
   GLfloat size, alphaAtten;

   CULL_INVALID(vert);

   /* z coord */
   if (ctx->DrawBuffer->Visual.depthBits <= 16)
      span.z = FloatToFixed(vert->attrib[FRAG_ATTRIB_WPOS][2] + 0.5F);
   else
      span.z = (GLuint) (vert->attrib[FRAG_ATTRIB_WPOS][2] + 0.5F);
   span.zStep = 0;

   size = get_size(ctx, vert, GL_TRUE);

   /* alpha attenuation / fade factor */
   if (ctx->Multisample._Enabled) {
      if (vert->pointSize >= ctx->Point.Threshold) {
         alphaAtten = 1.0F;
      }
      else {
         GLfloat dsize = vert->pointSize / ctx->Point.Threshold;
         alphaAtten = dsize * dsize;
      }
   }
   else {
      alphaAtten = 1.0;
   }
   (void) alphaAtten; /* not used */

   /* span init */
   INIT_SPAN(span, GL_POINT);
   span.interpMask = SPAN_Z | SPAN_RGBA;
   span.arrayMask = SPAN_COVERAGE | SPAN_MASK;

   span.facing = swrast->PointLineFacing;

   span.red   = ChanToFixed(vert->color[0]);
   span.green = ChanToFixed(vert->color[1]);
   span.blue  = ChanToFixed(vert->color[2]);
   span.alpha = ChanToFixed(vert->color[3]);
   span.redStep = 0;
   span.greenStep = 0;
   span.blueStep = 0;
   span.alphaStep = 0;

   /* need these for fragment programs */
   span.attrStart[FRAG_ATTRIB_WPOS][3] = 1.0F;
   span.attrStepX[FRAG_ATTRIB_WPOS][3] = 0.0F;
   span.attrStepY[FRAG_ATTRIB_WPOS][3] = 0.0F;

   ATTRIB_LOOP_BEGIN
      COPY_4V(span.attrStart[attr], vert->attrib[attr]);
      ASSIGN_4V(span.attrStepX[attr], 0, 0, 0, 0);
      ASSIGN_4V(span.attrStepY[attr], 0, 0, 0, 0);
   ATTRIB_LOOP_END

   /* compute pos, bounds and render */
   {
      const GLfloat x = vert->attrib[FRAG_ATTRIB_WPOS][0];
      const GLfloat y = vert->attrib[FRAG_ATTRIB_WPOS][1];
      const GLfloat radius = 0.5F * size;
      const GLfloat rmin = radius - 0.7071F;  /* 0.7071 = sqrt(2)/2 */
      const GLfloat rmax = radius + 0.7071F;
      const GLfloat rmin2 = MAX2(0.0F, rmin * rmin);
      const GLfloat rmax2 = rmax * rmax;
      const GLfloat cscale = 1.0F / (rmax2 - rmin2);
      const GLint xmin = (GLint) (x - radius);
      const GLint xmax = (GLint) (x + radius);
      const GLint ymin = (GLint) (y - radius);
      const GLint ymax = (GLint) (y + radius);
      GLint ix, iy;

      for (iy = ymin; iy <= ymax; iy++) {

         /* these might get changed by span clipping */
         span.x = xmin;
         span.y = iy;
         span.end = xmax - xmin + 1;

         /* compute coverage for each pixel in span */
         for (ix = xmin; ix <= xmax; ix++) {
            const GLfloat dx = ix - x + 0.5F;
            const GLfloat dy = iy - y + 0.5F;
            const GLfloat dist2 = dx * dx + dy * dy;
            GLfloat coverage;

            if (dist2 < rmax2) {
               if (dist2 >= rmin2) {
                  /* compute partial coverage */
                  coverage = 1.0F - (dist2 - rmin2) * cscale;
                  if (ciMode) {
                     /* coverage in [0,15] */
                     coverage *= 15.0;
                  }
               }
               else {
                  /* full coverage */
                  coverage = 1.0F;
               }
               span.array->mask[ix - xmin] = 1;
            }
            else {
               /* zero coverage - fragment outside the radius */
               coverage = 0.0;
               span.array->mask[ix - xmin] = 0;
            }
            span.array->coverage[ix - xmin] = coverage;
         }

         /* render span */
         _swrast_write_rgba_span(ctx, &span);

      }
   }
}
Exemplo n.º 9
0
/*
 * Draw depth image.
 */
static void
draw_depth_pixels( struct gl_context *ctx, GLint x, GLint y,
                   GLsizei width, GLsizei height,
                   GLenum type,
                   const struct gl_pixelstore_attrib *unpack,
                   const GLvoid *pixels )
{
   const GLboolean scaleOrBias
      = ctx->Pixel.DepthScale != 1.0 || ctx->Pixel.DepthBias != 0.0;
   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0 || ctx->Pixel.ZoomY != 1.0;
   SWspan span;

   INIT_SPAN(span, GL_BITMAP);
   span.arrayMask = SPAN_Z;
   _swrast_span_default_attribs(ctx, &span);

   if (type == GL_UNSIGNED_SHORT
       && ctx->DrawBuffer->Visual.depthBits == 16
       && !scaleOrBias
       && !zoom
       && width <= SWRAST_MAX_WIDTH
       && !unpack->SwapBytes) {
      /* Special case: directly write 16-bit depth values */
      GLint row;
      for (row = 0; row < height; row++) {
         const GLushort *zSrc = (const GLushort *)
            _mesa_image_address2d(unpack, pixels, width, height,
                                  GL_DEPTH_COMPONENT, type, row, 0);
         GLint i;
         for (i = 0; i < width; i++)
            span.array->z[i] = zSrc[i];
         span.x = x;
         span.y = y + row;
         span.end = width;
         _swrast_write_rgba_span(ctx, &span);
      }
   }
   else if (type == GL_UNSIGNED_INT
            && !scaleOrBias
            && !zoom
            && width <= SWRAST_MAX_WIDTH
            && !unpack->SwapBytes) {
      /* Special case: shift 32-bit values down to Visual.depthBits */
      const GLint shift = 32 - ctx->DrawBuffer->Visual.depthBits;
      GLint row;
      for (row = 0; row < height; row++) {
         const GLuint *zSrc = (const GLuint *)
            _mesa_image_address2d(unpack, pixels, width, height,
                                  GL_DEPTH_COMPONENT, type, row, 0);
         if (shift == 0) {
            memcpy(span.array->z, zSrc, width * sizeof(GLuint));
         }
         else {
            GLint col;
            for (col = 0; col < width; col++)
               span.array->z[col] = zSrc[col] >> shift;
         }
         span.x = x;
         span.y = y + row;
         span.end = width;
         _swrast_write_rgba_span(ctx, &span);
      }
   }
   else {
Exemplo n.º 10
0
/*
 * Draw depth image.
 */
static void
draw_depth_pixels( GLcontext *ctx, GLint x, GLint y,
                   GLsizei width, GLsizei height,
                   GLenum type,
                   const struct gl_pixelstore_attrib *unpack,
                   const GLvoid *pixels )
{
   const GLboolean bias_or_scale = ctx->Pixel.DepthBias!=0.0 || ctx->Pixel.DepthScale!=1.0;
   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0 || ctx->Pixel.ZoomY != 1.0;
   const GLint desty = y;
   struct sw_span span;

   INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_Z);

   if (type != GL_BYTE
       && type != GL_UNSIGNED_BYTE
       && type != GL_SHORT
       && type != GL_UNSIGNED_SHORT
       && type != GL_INT
       && type != GL_UNSIGNED_INT
       && type != GL_FLOAT) {
      _mesa_error(ctx, GL_INVALID_ENUM, "glDrawPixels(type)");
      return;
   }

   _swrast_span_default_color(ctx, &span);

   if (ctx->Fog.Enabled)
      _swrast_span_default_fog(ctx, &span);
   if (ctx->Texture._EnabledCoordUnits)
      _swrast_span_default_texcoords(ctx, &span);

   if (type == GL_UNSIGNED_SHORT
       && ctx->Visual.depthBits == 16
       && !bias_or_scale
       && !zoom
       && ctx->Visual.rgbMode
       && width <= MAX_WIDTH) {
      /* Special case: directly write 16-bit depth values */
      GLint row, spanY = y;
      for (row = 0; row < height; row++, spanY++) {
         const GLushort *zSrc = (const GLushort *)
            _mesa_image_address2d(unpack, pixels, width, height,
                                  GL_DEPTH_COMPONENT, type, row, 0);
         GLint i;
         for (i = 0; i < width; i++)
            span.array->z[i] = zSrc[i];
         span.x = x;
         span.y = spanY;
         span.end = width;
         _swrast_write_rgba_span(ctx, &span);
      }
   }
   else if (type == GL_UNSIGNED_INT
            && sizeof(GLdepth) == 4
            && !bias_or_scale
            && !zoom
            && ctx->Visual.rgbMode
            && width <= MAX_WIDTH) {
      /* Special case: shift 32-bit values down to ctx->Visual.depthBits */
      const GLint shift = 32 - ctx->Visual.depthBits;
      GLint row, spanY = y;
      for (row = 0; row < height; row++, spanY++) {
         const GLuint *zSrc = (const GLuint *)
            _mesa_image_address2d(unpack, pixels, width, height,
                                  GL_DEPTH_COMPONENT, type, row, 0);
         if (shift == 0) {
            MEMCPY(span.array->z, zSrc, width * sizeof(GLdepth));
         }
         else {
            GLint col;
            for (col = 0; col < width; col++)
               span.array->z[col] = zSrc[col] >> shift;
         }
         span.x = x;
         span.y = spanY;
         span.end = width;
         _swrast_write_rgba_span(ctx, &span);
      }
   }
   else {
Exemplo n.º 11
0
/**
 * RGBA copypixels with convolution.
 */
static void
copy_conv_rgba_pixels(GLcontext *ctx, GLint srcx, GLint srcy,
                      GLint width, GLint height, GLint destx, GLint desty)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   GLint row;
   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
   const GLbitfield transferOps = ctx->_ImageTransferState;
   const GLboolean sink = (ctx->Pixel.MinMaxEnabled && ctx->MinMax.Sink)
      || (ctx->Pixel.HistogramEnabled && ctx->Histogram.Sink);
   GLfloat *dest, *tmpImage, *convImage;
   SWspan span;

   INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_RGBA);

   if (ctx->Depth.Test)
      _swrast_span_default_z(ctx, &span);
   if (swrast->_FogEnabled)
      _swrast_span_default_fog(ctx, &span);
   _swrast_span_default_secondary_color(ctx, &span);

   /* allocate space for GLfloat image */
   tmpImage = (GLfloat *) _mesa_malloc(width * height * 4 * sizeof(GLfloat));
   if (!tmpImage) {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
      return;
   }
   convImage = (GLfloat *) _mesa_malloc(width * height * 4 * sizeof(GLfloat));
   if (!convImage) {
      _mesa_free(tmpImage);
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
      return;
   }

   /* read source image as float/RGBA */
   dest = tmpImage;
   for (row = 0; row < height; row++) {
      _swrast_read_rgba_span(ctx, ctx->ReadBuffer->_ColorReadBuffer,
                             width, srcx, srcy + row, GL_FLOAT, dest);
      dest += 4 * width;
   }

   /* do the image transfer ops which preceed convolution */
   for (row = 0; row < height; row++) {
      GLfloat (*rgba)[4] = (GLfloat (*)[4]) (tmpImage + row * width * 4);
      _mesa_apply_rgba_transfer_ops(ctx,
                                    transferOps & IMAGE_PRE_CONVOLUTION_BITS,
                                    width, rgba);
   }

   /* do convolution */
   if (ctx->Pixel.Convolution2DEnabled) {
      _mesa_convolve_2d_image(ctx, &width, &height, tmpImage, convImage);
   }
   else {
      ASSERT(ctx->Pixel.Separable2DEnabled);
      _mesa_convolve_sep_image(ctx, &width, &height, tmpImage, convImage);
   }
   _mesa_free(tmpImage);

   /* do remaining post-convolution image transfer ops */
   for (row = 0; row < height; row++) {
      GLfloat (*rgba)[4] = (GLfloat (*)[4]) (convImage + row * width * 4);
      _mesa_apply_rgba_transfer_ops(ctx,
                                    transferOps & IMAGE_POST_CONVOLUTION_BITS,
                                    width, rgba);
   }

   if (!sink) {
      /* write the new image */
      for (row = 0; row < height; row++) {
         const GLfloat *src = convImage + row * width * 4;
         GLvoid *rgba = (GLvoid *) span.array->attribs[FRAG_ATTRIB_COL0];

         /* copy convolved colors into span array */
         _mesa_memcpy(rgba, src, width * 4 * sizeof(GLfloat));

         /* write span */
         span.x = destx;
         span.y = desty + row;
         span.end = width;
         span.array->ChanType = GL_FLOAT;
         if (zoom) {
            _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span, rgba);
         }
         else {
            _swrast_write_rgba_span(ctx, &span);
         }
      }
      /* restore this */
      span.array->ChanType = CHAN_TYPE;
   }

   _mesa_free(convImage);
}
Exemplo n.º 12
0
/**
 * RGBA copypixels
 */
static void
copy_rgba_pixels(GLcontext *ctx, GLint srcx, GLint srcy,
                 GLint width, GLint height, GLint destx, GLint desty)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   GLfloat *tmpImage, *p;
   GLint sy, dy, stepy, row;
   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
   GLint overlapping;
   GLuint transferOps = ctx->_ImageTransferState;
   SWspan span;

   if (!ctx->ReadBuffer->_ColorReadBuffer) {
      /* no readbuffer - OK */
      return;
   }

   if (ctx->Pixel.Convolution2DEnabled || ctx->Pixel.Separable2DEnabled) {
      copy_conv_rgba_pixels(ctx, srcx, srcy, width, height, destx, desty);
      return;
   }
   else if (ctx->Pixel.Convolution1DEnabled) {
      /* make sure we don't apply 1D convolution */
      transferOps &= ~(IMAGE_CONVOLUTION_BIT |
                       IMAGE_POST_CONVOLUTION_SCALE_BIAS);
   }

   if (ctx->DrawBuffer == ctx->ReadBuffer) {
      overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
                                    ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
   }
   else {
      overlapping = GL_FALSE;
   }

   /* Determine if copy should be done bottom-to-top or top-to-bottom */
   if (!overlapping && srcy < desty) {
      /* top-down  max-to-min */
      sy = srcy + height - 1;
      dy = desty + height - 1;
      stepy = -1;
   }
   else {
      /* bottom-up  min-to-max */
      sy = srcy;
      dy = desty;
      stepy = 1;
   }

   INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_RGBA);
   if (ctx->Depth.Test)
      _swrast_span_default_z(ctx, &span);
   if (swrast->_FogEnabled)
      _swrast_span_default_fog(ctx, &span);
   _swrast_span_default_secondary_color(ctx, &span);

   if (overlapping) {
      tmpImage = (GLfloat *) _mesa_malloc(width * height * sizeof(GLfloat) * 4);
      if (!tmpImage) {
         _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
         return;
      }
      /* read the source image as RGBA/float */
      p = tmpImage;
      for (row = 0; row < height; row++) {
         _swrast_read_rgba_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
                                 width, srcx, sy + row, GL_FLOAT, p );
         p += width * 4;
      }
      p = tmpImage;
   }
   else {
      tmpImage = NULL;  /* silence compiler warnings */
      p = NULL;
   }

   ASSERT(width < MAX_WIDTH);

   for (row = 0; row < height; row++, sy += stepy, dy += stepy) {
      GLvoid *rgba = span.array->attribs[FRAG_ATTRIB_COL0];

      /* Get row/span of source pixels */
      if (overlapping) {
         /* get from buffered image */
         _mesa_memcpy(rgba, p, width * sizeof(GLfloat) * 4);
         p += width * 4;
      }
      else {
         /* get from framebuffer */
         _swrast_read_rgba_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
                                 width, srcx, sy, GL_FLOAT, rgba );
      }

      if (transferOps) {
         _mesa_apply_rgba_transfer_ops(ctx, transferOps, width,
                                       (GLfloat (*)[4]) rgba);
      }

      /* Write color span */
      span.x = destx;
      span.y = dy;
      span.end = width;
      span.array->ChanType = GL_FLOAT;
      if (zoom) {
         _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span, rgba);
      }
      else {
         _swrast_write_rgba_span(ctx, &span);
      }
   }

   span.array->ChanType = CHAN_TYPE; /* restore */

   if (overlapping)
      _mesa_free(tmpImage);
}
Exemplo n.º 13
0
/*
 * TODO: Optimize!!!!
 */
static void
copy_depth_pixels( GLcontext *ctx, GLint srcx, GLint srcy,
                   GLint width, GLint height,
                   GLint destx, GLint desty )
{
   struct gl_framebuffer *fb = ctx->ReadBuffer;
   struct gl_renderbuffer *readRb = fb->_DepthBuffer;
   GLfloat *p, *tmpImage;
   GLint sy, dy, stepy;
   GLint j;
   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
   GLint overlapping;
   SWspan span;

   if (!readRb) {
      /* no readbuffer - OK */
      return;
   }

   INIT_SPAN(span, GL_BITMAP);
   _swrast_span_default_attribs(ctx, &span);
   span.arrayMask = SPAN_Z;

   if (ctx->DrawBuffer == ctx->ReadBuffer) {
      overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
                                    ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
   }
   else {
      overlapping = GL_FALSE;
   }

   /* Determine if copy should be bottom-to-top or top-to-bottom */
   if (!overlapping && srcy < desty) {
      /* top-down  max-to-min */
      sy = srcy + height - 1;
      dy = desty + height - 1;
      stepy = -1;
   }
   else {
      /* bottom-up  min-to-max */
      sy = srcy;
      dy = desty;
      stepy = 1;
   }

   if (overlapping) {
      GLint ssy = sy;
      tmpImage = (GLfloat *) malloc(width * height * sizeof(GLfloat));
      if (!tmpImage) {
         _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
         return;
      }
      p = tmpImage;
      for (j = 0; j < height; j++, ssy += stepy) {
         _swrast_read_depth_span_float(ctx, readRb, width, srcx, ssy, p);
         p += width;
      }
      p = tmpImage;
   }
   else {
      tmpImage = NULL;  /* silence compiler warning */
      p = NULL;
   }

   for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
      GLfloat depth[MAX_WIDTH];
      /* get depth values */
      if (overlapping) {
         memcpy(depth, p, width * sizeof(GLfloat));
         p += width;
      }
      else {
         _swrast_read_depth_span_float(ctx, readRb, width, srcx, sy, depth);
      }

      /* apply scale and bias */
      scale_and_bias_z(ctx, width, depth, span.array->z);

      /* write depth values */
      span.x = destx;
      span.y = dy;
      span.end = width;
      if (zoom)
         _swrast_write_zoomed_depth_span(ctx, destx, desty, &span);
      else
         _swrast_write_rgba_span(ctx, &span);
   }

   if (overlapping)
      free(tmpImage);
}
Exemplo n.º 14
0
/*
 * Helper function called from _swrast_write_zoomed_rgba/rgb/index_span().
 */
static void
zoom_span( GLcontext *ctx, const struct sw_span *span,
           const GLvoid *src, GLint y0, GLenum format, GLint skipPixels )
{
   GLint r0, r1, row;
   GLint c0, c1, skipCol;
   GLint i, j;
   const GLuint maxWidth = MIN2( ctx->DrawBuffer->Width, MAX_WIDTH );
   struct sw_span zoomed;
   struct span_arrays zoomed_arrays;  /* this is big! */

   /* no pixel arrays! must be horizontal spans. */
   ASSERT((span->arrayMask & SPAN_XY) == 0);
   ASSERT(span->primitive == GL_BITMAP);

   INIT_SPAN(zoomed, GL_BITMAP, 0, 0, 0);
   zoomed.array = &zoomed_arrays;

   /* copy fog interp info */
   zoomed.fog = span->fog;
   zoomed.fogStep = span->fogStep;
   /* XXX copy texcoord info? */

   if (format == GL_RGBA || format == GL_RGB) {
      /* copy Z info */
      zoomed.z = span->z;
      zoomed.zStep = span->zStep;
      /* we'll generate an array of colorss */
      zoomed.interpMask = span->interpMask & ~SPAN_RGBA;
      zoomed.arrayMask |= SPAN_RGBA;
   }
   else if (format == GL_COLOR_INDEX) {
      /* copy Z info */
      zoomed.z = span->z;
      zoomed.zStep = span->zStep;
      /* we'll generate an array of color indexes */
      zoomed.interpMask = span->interpMask & ~SPAN_INDEX;
      zoomed.arrayMask |= SPAN_INDEX;
   }
   else {
      assert(format == GL_DEPTH_COMPONENT);
      /* Copy color info */
      zoomed.red = span->red;
      zoomed.green = span->green;
      zoomed.blue = span->blue;
      zoomed.alpha = span->alpha;
      zoomed.redStep = span->redStep;
      zoomed.greenStep = span->greenStep;
      zoomed.blueStep = span->blueStep;
      zoomed.alphaStep = span->alphaStep;
      /* we'll generate an array of depth values */
      zoomed.interpMask = span->interpMask & ~SPAN_Z;
      zoomed.arrayMask |= SPAN_Z;
   }

   /*
    * Compute which columns to draw: [c0, c1)
    */
   c0 = (GLint) (span->x + skipPixels * ctx->Pixel.ZoomX);
   c1 = (GLint) (span->x + (skipPixels + span->end) * ctx->Pixel.ZoomX);
   if (c0 == c1) {
      return;
   }
   else if (c1 < c0) {
      /* swap */
      GLint ctmp = c1;
      c1 = c0;
      c0 = ctmp;
   }
   if (c0 < 0) {
      zoomed.x = 0;
      zoomed.start = 0;
      zoomed.end = c1;
      skipCol = -c0;
   }
   else {
      zoomed.x = c0;
      zoomed.start = 0;
      zoomed.end = c1 - c0;
      skipCol = 0;
   }
   if (zoomed.end > maxWidth)
      zoomed.end = maxWidth;

   /*
    * Compute which rows to draw: [r0, r1)
    */
   row = span->y - y0;
   r0 = y0 + (GLint) (row * ctx->Pixel.ZoomY);
   r1 = y0 + (GLint) ((row+1) * ctx->Pixel.ZoomY);
   if (r0 == r1) {
      return;
   }
   else if (r1 < r0) {
      /* swap */
      GLint rtmp = r1;
      r1 = r0;
      r0 = rtmp;
   }

   ASSERT(r0 < r1);
   ASSERT(c0 < c1);

   /*
    * Trivial clip rejection testing.
    */
   if (r1 < 0) /* below window */
      return;
   if (r0 >= (GLint) ctx->DrawBuffer->Height) /* above window */
      return;
   if (c1 < 0) /* left of window */
      return;
   if (c0 >= (GLint) ctx->DrawBuffer->Width) /* right of window */
      return;

   /* zoom the span horizontally */
   if (format == GL_RGBA) {
      const GLchan (*rgba)[4] = (const GLchan (*)[4]) src;
      if (ctx->Pixel.ZoomX == -1.0F) {
         /* common case */
         for (j = (GLint) zoomed.start; j < (GLint) zoomed.end; j++) {
            i = span->end - (j + skipCol) - 1;
            COPY_CHAN4(zoomed.array->rgba[j], rgba[i]);
         }
      }
      else {
         /* general solution */
         const GLfloat xscale = 1.0F / ctx->Pixel.ZoomX;
         for (j = (GLint) zoomed.start; j < (GLint) zoomed.end; j++) {
            i = (GLint) ((j + skipCol) * xscale);
            if (ctx->Pixel.ZoomX < 0.0) {
               ASSERT(i <= 0);
               i = span->end + i - 1;
            }
            ASSERT(i >= 0);
            ASSERT(i < (GLint)  span->end);
            COPY_CHAN4(zoomed.array->rgba[j], rgba[i]);
         }
      }
   }
   else if (format == GL_RGB) {
      const GLchan (*rgb)[3] = (const GLchan (*)[3]) src;
      if (ctx->Pixel.ZoomX == -1.0F) {
         /* common case */
         for (j = (GLint) zoomed.start; j < (GLint) zoomed.end; j++) {
            i = span->end - (j + skipCol) - 1;
            zoomed.array->rgba[j][0] = rgb[i][0];
            zoomed.array->rgba[j][1] = rgb[i][1];
            zoomed.array->rgba[j][2] = rgb[i][2];
            zoomed.array->rgba[j][3] = CHAN_MAX;
         }
      }
      else {
         /* general solution */
         const GLfloat xscale = 1.0F / ctx->Pixel.ZoomX;
         for (j = (GLint) zoomed.start; j < (GLint) zoomed.end; j++) {
            i = (GLint) ((j + skipCol) * xscale);
            if (ctx->Pixel.ZoomX < 0.0) {
               ASSERT(i <= 0);
               i = span->end + i - 1;
            }
            ASSERT(i >= 0);
            ASSERT(i < (GLint) span->end);
            zoomed.array->rgba[j][0] = rgb[i][0];
            zoomed.array->rgba[j][1] = rgb[i][1];
            zoomed.array->rgba[j][2] = rgb[i][2];
            zoomed.array->rgba[j][3] = CHAN_MAX;
         }
      }
   }
   else if (format == GL_COLOR_INDEX) {
      const GLuint *indexes = (const GLuint *) src;
      if (ctx->Pixel.ZoomX == -1.0F) {
         /* common case */
         for (j = (GLint) zoomed.start; j < (GLint) zoomed.end; j++) {
            i = span->end - (j + skipCol) - 1;
            zoomed.array->index[j] = indexes[i];
         }
      }
      else {
         /* general solution */
         const GLfloat xscale = 1.0F / ctx->Pixel.ZoomX;
         for (j = (GLint) zoomed.start; j < (GLint) zoomed.end; j++) {
            i = (GLint) ((j + skipCol) * xscale);
            if (ctx->Pixel.ZoomX < 0.0) {
               ASSERT(i <= 0);
               i = span->end + i - 1;
            }
            ASSERT(i >= 0);
            ASSERT(i < (GLint) span->end);
            zoomed.array->index[j] = indexes[i];
         }
      }
   }
   else {
      const GLdepth *zValues = (const GLuint *) src;
      assert(format == GL_DEPTH_COMPONENT);
      if (ctx->Pixel.ZoomX == -1.0F) {
         /* common case */
         for (j = (GLint) zoomed.start; j < (GLint) zoomed.end; j++) {
            i = span->end - (j + skipCol) - 1;
            zoomed.array->z[j] = zValues[i];
         }
      }
      else {
         /* general solution */
         const GLfloat xscale = 1.0F / ctx->Pixel.ZoomX;
         for (j = (GLint) zoomed.start; j < (GLint) zoomed.end; j++) {
            i = (GLint) ((j + skipCol) * xscale);
            if (ctx->Pixel.ZoomX < 0.0) {
               ASSERT(i <= 0);
               i = span->end + i - 1;
            }
            ASSERT(i >= 0);
            ASSERT(i < (GLint) span->end);
            zoomed.array->z[j] = zValues[i];
         }
      }
      /* Now, fall into either the RGB or COLOR_INDEX path below */
      if (ctx->Visual.rgbMode)
         format = GL_RGBA;
      else
         format = GL_COLOR_INDEX;
   }


   /* write the span in rows [r0, r1) */
   if (format == GL_RGBA || format == GL_RGB) {
      /* Writing the span may modify the colors, so make a backup now if we're
       * going to call _swrast_write_zoomed_span() more than once.
       * Also, clipping may change the span end value, so store it as well.
       */
      GLchan rgbaSave[MAX_WIDTH][4];
      const GLint end = zoomed.end; /* save */
      if (r1 - r0 > 1) {
         MEMCPY(rgbaSave, zoomed.array->rgba, zoomed.end * 4 * sizeof(GLchan));
      }
      for (zoomed.y = r0; zoomed.y < r1; zoomed.y++) {
         _swrast_write_rgba_span(ctx, &zoomed);
         zoomed.end = end;  /* restore */
         if (r1 - r0 > 1) {
            /* restore the colors */
            MEMCPY(zoomed.array->rgba, rgbaSave, zoomed.end*4 * sizeof(GLchan));
         }
      }
   }
   else if (format == GL_COLOR_INDEX) {
      GLuint indexSave[MAX_WIDTH];
      const GLint end = zoomed.end; /* save */
      if (r1 - r0 > 1) {
         MEMCPY(indexSave, zoomed.array->index, zoomed.end * sizeof(GLuint));
      }
      for (zoomed.y = r0; zoomed.y < r1; zoomed.y++) {
         _swrast_write_index_span(ctx, &zoomed);
         zoomed.end = end;  /* restore */
         if (r1 - r0 > 1) {
            /* restore the colors */
            MEMCPY(zoomed.array->index, indexSave, zoomed.end * sizeof(GLuint));
         }
      }
   }
}
Exemplo n.º 15
0
/*
 * XXX this is another way to implement Bitmap.  Use horizontal runs of
 * fragments, initializing the mask array to indicate which fragments to
 * draw or skip.
 */
void
_swrast_Bitmap( struct gl_context *ctx, GLint px, GLint py,
		GLsizei width, GLsizei height,
		const struct gl_pixelstore_attrib *unpack,
		const GLubyte *bitmap )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   GLint row, col;
   SWspan span;

   ASSERT(ctx->RenderMode == GL_RENDER);
   ASSERT(bitmap);

   swrast_render_start(ctx);

   if (SWRAST_CONTEXT(ctx)->NewState)
      _swrast_validate_derived( ctx );

   INIT_SPAN(span, GL_BITMAP);
   span.end = width;
   span.arrayMask = SPAN_MASK;
   _swrast_span_default_attribs(ctx, &span);

   /*span.arrayMask |= SPAN_MASK;*/  /* we'll init span.mask[] */
   span.x = px;
   span.y = py;
   /*span.end = width;*/

   for (row=0; row<height; row++, span.y++) {
      const GLubyte *src = (const GLubyte *) _mesa_image_address2d(unpack,
                 bitmap, width, height, GL_COLOR_INDEX, GL_BITMAP, row, 0);

      if (unpack->LsbFirst) {
         /* Lsb first */
         GLubyte mask = 1U << (unpack->SkipPixels & 0x7);
         for (col=0; col<width; col++) {
            span.array->mask[col] = (*src & mask) ? GL_TRUE : GL_FALSE;
            if (mask == 128U) {
               src++;
               mask = 1U;
            }
            else {
               mask = mask << 1;
            }
         }

         _swrast_write_rgba_span(ctx, &span);

         /* get ready for next row */
         if (mask != 1)
            src++;
      }
      else {
         /* Msb first */
         GLubyte mask = 128U >> (unpack->SkipPixels & 0x7);
         for (col=0; col<width; col++) {
            span.array->mask[col] = (*src & mask) ? GL_TRUE : GL_FALSE;
            if (mask == 1U) {
               src++;
               mask = 128U;
            }
            else {
               mask = mask >> 1;
            }
         }

         _swrast_write_rgba_span(ctx, &span);

         /* get ready for next row */
         if (mask != 128)
            src++;
      }
   }

   swrast_render_finish(ctx);
}
Exemplo n.º 16
0
/**
 * Render a bitmap.
 * Called via ctx->Driver.Bitmap()
 * All parameter error checking will have been done before this is called.
 */
void
_swrast_Bitmap( struct gl_context *ctx, GLint px, GLint py,
		GLsizei width, GLsizei height,
		const struct gl_pixelstore_attrib *unpack,
		const GLubyte *bitmap )
{
   GLint row, col;
   GLuint count = 0;
   SWspan span;

   ASSERT(ctx->RenderMode == GL_RENDER);

   if (!_mesa_check_conditional_render(ctx))
      return; /* don't draw */

   bitmap = (const GLubyte *) _mesa_map_pbo_source(ctx, unpack, bitmap);
   if (!bitmap)
      return;

   swrast_render_start(ctx);

   if (SWRAST_CONTEXT(ctx)->NewState)
      _swrast_validate_derived( ctx );

   INIT_SPAN(span, GL_BITMAP);
   span.end = width;
   span.arrayMask = SPAN_XY;
   _swrast_span_default_attribs(ctx, &span);

   for (row = 0; row < height; row++) {
      const GLubyte *src = (const GLubyte *) _mesa_image_address2d(unpack,
                 bitmap, width, height, GL_COLOR_INDEX, GL_BITMAP, row, 0);

      if (unpack->LsbFirst) {
         /* Lsb first */
         GLubyte mask = 1U << (unpack->SkipPixels & 0x7);
         for (col = 0; col < width; col++) {
            if (*src & mask) {
               span.array->x[count] = px + col;
               span.array->y[count] = py + row;
               count++;
            }
            if (mask == 128U) {
               src++;
               mask = 1U;
            }
            else {
               mask = mask << 1;
            }
         }

         /* get ready for next row */
         if (mask != 1)
            src++;
      }
      else {
         /* Msb first */
         GLubyte mask = 128U >> (unpack->SkipPixels & 0x7);
         for (col = 0; col < width; col++) {
            if (*src & mask) {
               span.array->x[count] = px + col;
               span.array->y[count] = py + row;
               count++;
            }
            if (mask == 1U) {
               src++;
               mask = 128U;
            }
            else {
               mask = mask >> 1;
            }
         }

         /* get ready for next row */
         if (mask != 128)
            src++;
      }

      if (count + width >= SWRAST_MAX_WIDTH || row + 1 == height) {
         /* flush the span */
         span.end = count;
         _swrast_write_rgba_span(ctx, &span);
         span.end = 0;
         count = 0;
      }
   }

   swrast_render_finish(ctx);

   _mesa_unmap_pbo_source(ctx, unpack);
}
Exemplo n.º 17
0
/*
 * RGBA copypixels with convolution.
 */
static void
copy_conv_rgba_pixels(GLcontext *ctx, GLint srcx, GLint srcy,
                      GLint width, GLint height, GLint destx, GLint desty)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   struct gl_renderbuffer *drawRb = NULL;
   GLboolean quick_draw;
   GLint row;
   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
   const GLuint transferOps = ctx->_ImageTransferState;
   GLfloat *dest, *tmpImage, *convImage;
   struct sw_span span;

   INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_RGBA);

   if (ctx->Depth.Test)
      _swrast_span_default_z(ctx, &span);
   if (swrast->_FogEnabled)
      _swrast_span_default_fog(ctx, &span);


   if (SWRAST_CONTEXT(ctx)->_RasterMask == 0
       && !zoom
       && destx >= 0
       && destx + width <= (GLint) ctx->DrawBuffer->Width) {
      quick_draw = GL_TRUE;
      drawRb = ctx->DrawBuffer->_ColorDrawBuffers[0][0];
   }
   else {
      quick_draw = GL_FALSE;
   }

   /* allocate space for GLfloat image */
   tmpImage = (GLfloat *) _mesa_malloc(width * height * 4 * sizeof(GLfloat));
   if (!tmpImage) {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
      return;
   }
   convImage = (GLfloat *) _mesa_malloc(width * height * 4 * sizeof(GLfloat));
   if (!convImage) {
      _mesa_free(tmpImage);
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
      return;
   }

   /* read source image */
   dest = tmpImage;
   for (row = 0; row < height; row++) {
      GLchan rgba[MAX_WIDTH][4];
      /* Read GLchan and convert to GLfloat */
      _swrast_read_rgba_span(ctx, ctx->ReadBuffer->_ColorReadBuffer,
                             width, srcx, srcy + row, rgba);
      chan_span_to_float(width, (CONST GLchan (*)[4]) rgba,
                         (GLfloat (*)[4]) dest);
      dest += 4 * width;
   }

   /* do the image transfer ops which preceed convolution */
   for (row = 0; row < height; row++) {
      GLfloat (*rgba)[4] = (GLfloat (*)[4]) (tmpImage + row * width * 4);
      _mesa_apply_rgba_transfer_ops(ctx,
                                    transferOps & IMAGE_PRE_CONVOLUTION_BITS,
                                    width, rgba);
   }

   /* do convolution */
   if (ctx->Pixel.Convolution2DEnabled) {
      _mesa_convolve_2d_image(ctx, &width, &height, tmpImage, convImage);
   }
   else {
      ASSERT(ctx->Pixel.Separable2DEnabled);
      _mesa_convolve_sep_image(ctx, &width, &height, tmpImage, convImage);
   }
   _mesa_free(tmpImage);

   /* do remaining post-convolution image transfer ops */
   for (row = 0; row < height; row++) {
      GLfloat (*rgba)[4] = (GLfloat (*)[4]) (convImage + row * width * 4);
      _mesa_apply_rgba_transfer_ops(ctx,
                                    transferOps & IMAGE_POST_CONVOLUTION_BITS,
                                    width, rgba);
   }

   /* write the new image */
   for (row = 0; row < height; row++) {
      const GLfloat *src = convImage + row * width * 4;
      GLint dy;

      /* convert floats back to chan */
      float_span_to_chan(width, (const GLfloat (*)[4]) src, span.array->rgba);

      /* write row to framebuffer */
      dy = desty + row;
      if (quick_draw && dy >= 0 && dy < (GLint) ctx->DrawBuffer->Height) {
         drawRb->PutRow(ctx, drawRb, width, destx, dy, span.array->rgba, NULL);
      }
      else {
         span.x = destx;
         span.y = dy;
         span.end = width;
         if (zoom) {
            _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span, 
                                        (CONST GLchan (*)[4])span.array->rgba);
         }
         else {
            _swrast_write_rgba_span(ctx, &span);
         }
      }
   }

   _mesa_free(convImage);
}
Exemplo n.º 18
0
/*
 * RGBA copypixels
 */
static void
copy_rgba_pixels(GLcontext *ctx, GLint srcx, GLint srcy,
                 GLint width, GLint height, GLint destx, GLint desty)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   struct gl_renderbuffer *drawRb;
   GLchan *tmpImage,*p;
   GLboolean quick_draw;
   GLint sy, dy, stepy, j;
   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
   GLint overlapping;
   const GLuint transferOps = ctx->_ImageTransferState;
   struct sw_span span;

   if (!ctx->ReadBuffer->_ColorReadBuffer) {
      /* no readbuffer - OK */
      return;
   }

   INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_RGBA);

   if (ctx->Pixel.Convolution2DEnabled || ctx->Pixel.Separable2DEnabled) {
      copy_conv_rgba_pixels(ctx, srcx, srcy, width, height, destx, desty);
      return;
   }

   /* Determine if copy should be done bottom-to-top or top-to-bottom */
   if (srcy < desty) {
      /* top-down  max-to-min */
      sy = srcy + height - 1;
      dy = desty + height - 1;
      stepy = -1;
   }
   else {
      /* bottom-up  min-to-max */
      sy = srcy;
      dy = desty;
      stepy = 1;
   }

   if (ctx->DrawBuffer == ctx->ReadBuffer) {
      overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
                                    ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
   }
   else {
      overlapping = GL_FALSE;
   }

   if (ctx->Depth.Test)
      _swrast_span_default_z(ctx, &span);
   if (swrast->_FogEnabled)
      _swrast_span_default_fog(ctx, &span);

   if (SWRAST_CONTEXT(ctx)->_RasterMask == 0
       && !zoom
       && destx >= 0
       && destx + width <= (GLint) ctx->DrawBuffer->Width) {
      quick_draw = GL_TRUE;
      drawRb = ctx->DrawBuffer->_ColorDrawBuffers[0][0];
   }
   else {
      quick_draw = GL_FALSE;
      drawRb = NULL;
   }

   if (overlapping) {
      GLint ssy = sy;
      tmpImage = (GLchan *) _mesa_malloc(width * height * sizeof(GLchan) * 4);
      if (!tmpImage) {
         _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
         return;
      }
      /* read the source image */
      p = tmpImage;
      for (j = 0; j < height; j++, ssy += stepy) {
         _swrast_read_rgba_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
                                 width, srcx, ssy, (GLchan (*)[4]) p );
         p += width * 4;
      }
      p = tmpImage;
   }
   else {
      tmpImage = NULL;  /* silence compiler warnings */
      p = NULL;
   }

   for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
      /* Get source pixels */
      if (overlapping) {
         /* get from buffered image */
         ASSERT(width < MAX_WIDTH);
         _mesa_memcpy(span.array->rgba, p, width * sizeof(GLchan) * 4);
         p += width * 4;
      }
      else {
         /* get from framebuffer */
         ASSERT(width < MAX_WIDTH);
         _swrast_read_rgba_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
                                 width, srcx, sy, span.array->rgba );
      }

      if (transferOps) {
         GLfloat rgbaFloat[MAX_WIDTH][4];
         /* convert to float, transfer, convert back to chan */
         chan_span_to_float(width, (CONST GLchan (*)[4]) span.array->rgba,
                            rgbaFloat);
         _mesa_apply_rgba_transfer_ops(ctx, transferOps, width, rgbaFloat);
         float_span_to_chan(width, (CONST GLfloat (*)[4]) rgbaFloat,
                            span.array->rgba);
      }

      /* Write color span */
      if (quick_draw && dy >= 0 && dy < (GLint) ctx->DrawBuffer->Height) {
         drawRb->PutRow(ctx, drawRb, width, destx, dy, span.array->rgba, NULL);
      }
      else {
         span.x = destx;
         span.y = dy;
         span.end = width;
         if (zoom) {
            _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span,
                                       (CONST GLchan (*)[4]) span.array->rgba);
         }
         else {
            _swrast_write_rgba_span(ctx, &span);
         }
      }
   }

   if (overlapping)
      _mesa_free(tmpImage);
}
Exemplo n.º 19
0
/*
 * TODO: Optimize!!!!
 */
static void
copy_depth_pixels( GLcontext *ctx, GLint srcx, GLint srcy,
                   GLint width, GLint height,
                   GLint destx, GLint desty )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   struct gl_framebuffer *fb = ctx->ReadBuffer;
   struct gl_renderbuffer *readRb = fb->_DepthBuffer;
   const GLfloat depthMax = fb->_DepthMaxF;
   GLfloat *p, *tmpImage;
   GLint sy, dy, stepy;
   GLint i, j;
   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
   GLint overlapping;
   struct sw_span span;

   if (!readRb) {
      /* no readbuffer - OK */
      return;
   }

   INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_Z);

   /* Determine if copy should be bottom-to-top or top-to-bottom */
   if (srcy<desty) {
      /* top-down  max-to-min */
      sy = srcy + height - 1;
      dy = desty + height - 1;
      stepy = -1;
   }
   else {
      /* bottom-up  min-to-max */
      sy = srcy;
      dy = desty;
      stepy = 1;
   }

   if (ctx->DrawBuffer == ctx->ReadBuffer) {
      overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
                                    ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
   }
   else {
      overlapping = GL_FALSE;
   }

   _swrast_span_default_color(ctx, &span);
   if (swrast->_FogEnabled)
      _swrast_span_default_fog(ctx, &span);

   if (overlapping) {
      GLint ssy = sy;
      tmpImage = (GLfloat *) _mesa_malloc(width * height * sizeof(GLfloat));
      if (!tmpImage) {
         _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
         return;
      }
      p = tmpImage;
      for (j = 0; j < height; j++, ssy += stepy) {
         _swrast_read_depth_span_float(ctx, readRb, width, srcx, ssy, p);
         p += width;
      }
      p = tmpImage;
   }
   else {
      tmpImage = NULL;  /* silence compiler warning */
      p = NULL;
   }

   for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
      GLfloat depth[MAX_WIDTH];
      /* get depth values */
      if (overlapping) {
         _mesa_memcpy(depth, p, width * sizeof(GLfloat));
         p += width;
      }
      else {
         _swrast_read_depth_span_float(ctx, readRb, width, srcx, sy, depth);
      }

      /* apply scale and bias */
      for (i = 0; i < width; i++) {
         GLfloat d = depth[i] * ctx->Pixel.DepthScale + ctx->Pixel.DepthBias;
         span.array->z[i] = (GLuint) (CLAMP(d, 0.0F, 1.0F) * depthMax);
      }

      /* write depth values */
      span.x = destx;
      span.y = dy;
      span.end = width;
      if (fb->Visual.rgbMode) {
         if (zoom)
            _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span, 
                                       (const GLchan (*)[4]) span.array->rgba);
         else
            _swrast_write_rgba_span(ctx, &span);
      }
      else {
         if (zoom)
            _swrast_write_zoomed_index_span(ctx, destx, desty, &span);
         else
            _swrast_write_index_span(ctx, &span);
      }
   }

   if (overlapping)
      _mesa_free(tmpImage);
}
Exemplo n.º 20
0
/**
 * Helper function called from _swrast_write_zoomed_rgba/rgb/
 * index/depth_span().
 */
static void
zoom_span( struct gl_context *ctx, GLint imgX, GLint imgY, const SWspan *span,
           const GLvoid *src, GLenum format )
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   SWspan zoomed;
   GLint x0, x1, y0, y1;
   GLint zoomedWidth;

   if (!compute_zoomed_bounds(ctx, imgX, imgY, span->x, span->y, span->end,
                              &x0, &x1, &y0, &y1)) {
      return;  /* totally clipped */
   }

   if (!swrast->ZoomedArrays) {
      /* allocate on demand */
      swrast->ZoomedArrays = (SWspanarrays *) CALLOC(sizeof(SWspanarrays));
      if (!swrast->ZoomedArrays)
         return;
   }

   zoomedWidth = x1 - x0;
   ASSERT(zoomedWidth > 0);
   ASSERT(zoomedWidth <= MAX_WIDTH);

   /* no pixel arrays! must be horizontal spans. */
   ASSERT((span->arrayMask & SPAN_XY) == 0);
   ASSERT(span->primitive == GL_BITMAP);

   INIT_SPAN(zoomed, GL_BITMAP);
   zoomed.x = x0;
   zoomed.end = zoomedWidth;
   zoomed.array = swrast->ZoomedArrays;
   zoomed.array->ChanType = span->array->ChanType;
   if (zoomed.array->ChanType == GL_UNSIGNED_BYTE)
      zoomed.array->rgba = (GLchan (*)[4]) zoomed.array->rgba8;
   else if (zoomed.array->ChanType == GL_UNSIGNED_SHORT)
      zoomed.array->rgba = (GLchan (*)[4]) zoomed.array->rgba16;
   else
      zoomed.array->rgba = (GLchan (*)[4]) zoomed.array->attribs[FRAG_ATTRIB_COL];

   COPY_4V(zoomed.attrStart[FRAG_ATTRIB_WPOS], span->attrStart[FRAG_ATTRIB_WPOS]);
   COPY_4V(zoomed.attrStepX[FRAG_ATTRIB_WPOS], span->attrStepX[FRAG_ATTRIB_WPOS]);
   COPY_4V(zoomed.attrStepY[FRAG_ATTRIB_WPOS], span->attrStepY[FRAG_ATTRIB_WPOS]);

   zoomed.attrStart[FRAG_ATTRIB_FOGC][0] = span->attrStart[FRAG_ATTRIB_FOGC][0];
   zoomed.attrStepX[FRAG_ATTRIB_FOGC][0] = span->attrStepX[FRAG_ATTRIB_FOGC][0];
   zoomed.attrStepY[FRAG_ATTRIB_FOGC][0] = span->attrStepY[FRAG_ATTRIB_FOGC][0];

   if (format == GL_RGBA || format == GL_RGB) {
      /* copy Z info */
      zoomed.z = span->z;
      zoomed.zStep = span->zStep;
      /* we'll generate an array of colorss */
      zoomed.interpMask = span->interpMask & ~SPAN_RGBA;
      zoomed.arrayMask |= SPAN_RGBA;
      zoomed.arrayAttribs |= FRAG_BIT_COL;  /* we'll produce these values */
      ASSERT(span->arrayMask & SPAN_RGBA);
   }
   else if (format == GL_DEPTH_COMPONENT) {
      /* Copy color info */
      zoomed.red = span->red;
      zoomed.green = span->green;
      zoomed.blue = span->blue;
      zoomed.alpha = span->alpha;
      zoomed.redStep = span->redStep;
      zoomed.greenStep = span->greenStep;
      zoomed.blueStep = span->blueStep;
      zoomed.alphaStep = span->alphaStep;
      /* we'll generate an array of depth values */
      zoomed.interpMask = span->interpMask & ~SPAN_Z;
      zoomed.arrayMask |= SPAN_Z;
      ASSERT(span->arrayMask & SPAN_Z);
   }
   else {
      _mesa_problem(ctx, "Bad format in zoom_span");
      return;
   }

   /* zoom the span horizontally */
   if (format == GL_RGBA) {
      if (zoomed.array->ChanType == GL_UNSIGNED_BYTE) {
         const GLubyte (*rgba)[4] = (const GLubyte (*)[4]) src;
         GLint i;
         for (i = 0; i < zoomedWidth; i++) {
            GLint j = unzoom_x(ctx->Pixel.ZoomX, imgX, x0 + i) - span->x;
            ASSERT(j >= 0);
            ASSERT(j < (GLint) span->end);
            COPY_4UBV(zoomed.array->rgba8[i], rgba[j]);
         }
      }
      else if (zoomed.array->ChanType == GL_UNSIGNED_SHORT) {
         const GLushort (*rgba)[4] = (const GLushort (*)[4]) src;
         GLint i;
         for (i = 0; i < zoomedWidth; i++) {
            GLint j = unzoom_x(ctx->Pixel.ZoomX, imgX, x0 + i) - span->x;
            ASSERT(j >= 0);
            ASSERT(j < (GLint) span->end);
            COPY_4V(zoomed.array->rgba16[i], rgba[j]);
         }
      }
      else {
         const GLfloat (*rgba)[4] = (const GLfloat (*)[4]) src;
         GLint i;
         for (i = 0; i < zoomedWidth; i++) {
            GLint j = unzoom_x(ctx->Pixel.ZoomX, imgX, x0 + i) - span->x;
            ASSERT(j >= 0);
            ASSERT(j < span->end);
            COPY_4V(zoomed.array->attribs[FRAG_ATTRIB_COL][i], rgba[j]);
         }
      }
   }
   else if (format == GL_RGB) {
      if (zoomed.array->ChanType == GL_UNSIGNED_BYTE) {
         const GLubyte (*rgb)[3] = (const GLubyte (*)[3]) src;
         GLint i;
         for (i = 0; i < zoomedWidth; i++) {
            GLint j = unzoom_x(ctx->Pixel.ZoomX, imgX, x0 + i) - span->x;
            ASSERT(j >= 0);
            ASSERT(j < (GLint) span->end);
            zoomed.array->rgba8[i][0] = rgb[j][0];
            zoomed.array->rgba8[i][1] = rgb[j][1];
            zoomed.array->rgba8[i][2] = rgb[j][2];
            zoomed.array->rgba8[i][3] = 0xff;
         }
      }
      else if (zoomed.array->ChanType == GL_UNSIGNED_SHORT) {
         const GLushort (*rgb)[3] = (const GLushort (*)[3]) src;
         GLint i;
         for (i = 0; i < zoomedWidth; i++) {
            GLint j = unzoom_x(ctx->Pixel.ZoomX, imgX, x0 + i) - span->x;
            ASSERT(j >= 0);
            ASSERT(j < (GLint) span->end);
            zoomed.array->rgba16[i][0] = rgb[j][0];
            zoomed.array->rgba16[i][1] = rgb[j][1];
            zoomed.array->rgba16[i][2] = rgb[j][2];
            zoomed.array->rgba16[i][3] = 0xffff;
         }
      }
      else {
         const GLfloat (*rgb)[3] = (const GLfloat (*)[3]) src;
         GLint i;
         for (i = 0; i < zoomedWidth; i++) {
            GLint j = unzoom_x(ctx->Pixel.ZoomX, imgX, x0 + i) - span->x;
            ASSERT(j >= 0);
            ASSERT(j < span->end);
            zoomed.array->attribs[FRAG_ATTRIB_COL][i][0] = rgb[j][0];
            zoomed.array->attribs[FRAG_ATTRIB_COL][i][1] = rgb[j][1];
            zoomed.array->attribs[FRAG_ATTRIB_COL][i][2] = rgb[j][2];
            zoomed.array->attribs[FRAG_ATTRIB_COL][i][3] = 1.0F;
         }
      }
   }
   else if (format == GL_DEPTH_COMPONENT) {
      const GLuint *zValues = (const GLuint *) src;
      GLint i;
      for (i = 0; i < zoomedWidth; i++) {
         GLint j = unzoom_x(ctx->Pixel.ZoomX, imgX, x0 + i) - span->x;
         ASSERT(j >= 0);
         ASSERT(j < (GLint) span->end);
         zoomed.array->z[i] = zValues[j];
      }
      /* Now, fall into the RGB path below */
      format = GL_RGBA;
   }

   /* write the span in rows [r0, r1) */
   if (format == GL_RGBA || format == GL_RGB) {
      /* Writing the span may modify the colors, so make a backup now if we're
       * going to call _swrast_write_zoomed_span() more than once.
       * Also, clipping may change the span end value, so store it as well.
       */
      const GLint end = zoomed.end; /* save */
      void *rgbaSave;
      const GLint pixelSize =
         (zoomed.array->ChanType == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) :
         ((zoomed.array->ChanType == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort)
          : 4 * sizeof(GLfloat));

      rgbaSave = malloc(zoomed.end * pixelSize);
      if (!rgbaSave) {
         return;
      }

      if (y1 - y0 > 1) {
         memcpy(rgbaSave, zoomed.array->rgba, zoomed.end * pixelSize);
      }
      for (zoomed.y = y0; zoomed.y < y1; zoomed.y++) {
         _swrast_write_rgba_span(ctx, &zoomed);
         zoomed.end = end;  /* restore */
         if (y1 - y0 > 1) {
            /* restore the colors */
            memcpy(zoomed.array->rgba, rgbaSave, zoomed.end * pixelSize);
         }
      }

      free(rgbaSave);
   }
}
Exemplo n.º 21
0
/**
 * RGBA copypixels
 */
static void
copy_rgba_pixels(struct gl_context *ctx, GLint srcx, GLint srcy,
                 GLint width, GLint height, GLint destx, GLint desty)
{
    GLfloat *tmpImage, *p;
    GLint sy, dy, stepy, row;
    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
    GLint overlapping;
    GLuint transferOps = ctx->_ImageTransferState;
    SWspan span;

    if (!ctx->ReadBuffer->_ColorReadBuffer) {
        /* no readbuffer - OK */
        return;
    }

    if (ctx->DrawBuffer == ctx->ReadBuffer) {
        overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
                                      ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
    }
    else {
        overlapping = GL_FALSE;
    }

    /* Determine if copy should be done bottom-to-top or top-to-bottom */
    if (!overlapping && srcy < desty) {
        /* top-down  max-to-min */
        sy = srcy + height - 1;
        dy = desty + height - 1;
        stepy = -1;
    }
    else {
        /* bottom-up  min-to-max */
        sy = srcy;
        dy = desty;
        stepy = 1;
    }

    INIT_SPAN(span, GL_BITMAP);
    _swrast_span_default_attribs(ctx, &span);
    span.arrayMask = SPAN_RGBA;
    span.arrayAttribs = VARYING_BIT_COL0; /* we'll fill in COL0 attrib values */

    if (overlapping) {
        tmpImage = malloc(width * height * sizeof(GLfloat) * 4);
        if (!tmpImage) {
            _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
            return;
        }
        /* read the source image as RGBA/float */
        p = tmpImage;
        for (row = 0; row < height; row++) {
            _swrast_read_rgba_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
                                    width, srcx, sy + row, p );
            p += width * 4;
        }
        p = tmpImage;
    }
    else {
        tmpImage = NULL;  /* silence compiler warnings */
        p = NULL;
    }

    ASSERT(width < SWRAST_MAX_WIDTH);

    for (row = 0; row < height; row++, sy += stepy, dy += stepy) {
        GLvoid *rgba = span.array->attribs[VARYING_SLOT_COL0];

        /* Get row/span of source pixels */
        if (overlapping) {
            /* get from buffered image */
            memcpy(rgba, p, width * sizeof(GLfloat) * 4);
            p += width * 4;
        }
        else {
            /* get from framebuffer */
            _swrast_read_rgba_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
                                    width, srcx, sy, rgba );
        }

        if (transferOps) {
            _mesa_apply_rgba_transfer_ops(ctx, transferOps, width,
                                          (GLfloat (*)[4]) rgba);
        }

        /* Write color span */
        span.x = destx;
        span.y = dy;
        span.end = width;
        span.array->ChanType = GL_FLOAT;
        if (zoom) {
            _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span, rgba);
        }
        else {
            _swrast_write_rgba_span(ctx, &span);
        }
    }

    span.array->ChanType = CHAN_TYPE; /* restore */

    if (overlapping)
        free(tmpImage);
}