/**
* Update the viewport transformation matrix. Depends on:
* - viewport pos/size
* - depthrange
* - window pos/size or FBO size
*/
void
intelCalcViewport(struct gl_context * ctx)
{
struct intel_context *intel = intel_context(ctx);
if (ctx->DrawBuffer->Name == 0) {
_math_matrix_viewport(&intel->ViewportMatrix,
ctx->Viewport.X,
ctx->DrawBuffer->Height - ctx->Viewport.Y,
ctx->Viewport.Width,
-ctx->Viewport.Height,
ctx->Viewport.Near,
ctx->Viewport.Far,
1.0);
} else {
_math_matrix_viewport(&intel->ViewportMatrix,
ctx->Viewport.X,
ctx->Viewport.Y,
ctx->Viewport.Width,
ctx->Viewport.Height,
ctx->Viewport.Near,
ctx->Viewport.Far,
1.0);
}
}
/**
* Called by glDepthRange
*
* \param nearval specifies the Z buffer value which should correspond to
* the near clip plane
* \param farval specifies the Z buffer value which should correspond to
* the far clip plane
*/
void GLAPIENTRY
_mesa_DepthRange( GLclampd nearval, GLclampd farval )
{
GET_CURRENT_CONTEXT(ctx);
ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
if (MESA_VERBOSE&VERBOSE_API)
_mesa_debug(ctx, "glDepthRange %f %f\n", nearval, farval);
ctx->Viewport.Near = (GLfloat) CLAMP( nearval, 0.0, 1.0 );
ctx->Viewport.Far = (GLfloat) CLAMP( farval, 0.0, 1.0 );
ctx->NewState |= _NEW_VIEWPORT;
#if 1
/* XXX remove this someday. Currently the DRI drivers rely on
* the WindowMap matrix being up to date in the driver's Viewport
* and DepthRange functions.
*/
_math_matrix_viewport(&ctx->Viewport._WindowMap,
ctx->Viewport.X, ctx->Viewport.Y,
ctx->Viewport.Width, ctx->Viewport.Height,
ctx->Viewport.Near, ctx->Viewport.Far,
ctx->DrawBuffer->_DepthMaxF);
#endif
if (ctx->Driver.DepthRange) {
(*ctx->Driver.DepthRange)( ctx, nearval, farval );
}
}
/**
* Initialize the context viewport attribute group.
*
* \param ctx GL context.
*
* \todo Move this to a new file with other 'viewport' routines.
*/
void _mesa_init_viewport( GLcontext *ctx )
{
GLfloat depthMax = 65535.0F; /* sorf of arbitrary */
/* Viewport group */
ctx->Viewport.X = 0;
ctx->Viewport.Y = 0;
ctx->Viewport.Width = 0;
ctx->Viewport.Height = 0;
ctx->Viewport.Near = 0.0;
ctx->Viewport.Far = 1.0;
_math_matrix_ctr(&ctx->Viewport._WindowMap);
_math_matrix_viewport(&ctx->Viewport._WindowMap, 0, 0, 0, 0,
0.0F, 1.0F, depthMax);
}
static void
update_viewport_matrix(GLcontext *ctx)
{
const GLfloat depthMax = ctx->DrawBuffer->_DepthMaxF;
ASSERT(depthMax > 0);
/* Compute scale and bias values. This is really driver-specific
* and should be maintained elsewhere if at all.
* NOTE: RasterPos uses this.
*/
_math_matrix_viewport(&ctx->Viewport._WindowMap,
ctx->Viewport.X, ctx->Viewport.Y,
ctx->Viewport.Width, ctx->Viewport.Height,
ctx->Viewport.Near, ctx->Viewport.Far,
depthMax);
}
/**
* Set new viewport parameters and update derived state (the _WindowMap
* matrix). Usually called from _mesa_Viewport().
*
* \param ctx GL context.
* \param x, y coordinates of the lower left corner of the viewport rectangle.
* \param width width of the viewport rectangle.
* \param height height of the viewport rectangle.
*/
void
_mesa_set_viewport( GLcontext *ctx, GLint x, GLint y,
GLsizei width, GLsizei height )
{
if (MESA_VERBOSE & VERBOSE_API)
_mesa_debug(ctx, "glViewport %d %d %d %d\n", x, y, width, height);
if (width < 0 || height < 0) {
_mesa_error( ctx, GL_INVALID_VALUE,
"glViewport(%d, %d, %d, %d)", x, y, width, height );
return;
}
/* clamp width and height to the implementation dependent range */
width = MIN2(width, (GLsizei) ctx->Const.MaxViewportWidth);
height = MIN2(height, (GLsizei) ctx->Const.MaxViewportHeight);
ctx->Viewport.X = x;
ctx->Viewport.Width = width;
ctx->Viewport.Y = y;
ctx->Viewport.Height = height;
ctx->NewState |= _NEW_VIEWPORT;
#if 1
/* XXX remove this someday. Currently the DRI drivers rely on
* the WindowMap matrix being up to date in the driver's Viewport
* and DepthRange functions.
*/
_math_matrix_viewport(&ctx->Viewport._WindowMap,
ctx->Viewport.X, ctx->Viewport.Y,
ctx->Viewport.Width, ctx->Viewport.Height,
ctx->Viewport.Near, ctx->Viewport.Far,
ctx->DrawBuffer->_DepthMaxF);
#endif
if (ctx->Driver.Viewport) {
/* Many drivers will use this call to check for window size changes
* and reallocate the z/stencil/accum/etc buffers if needed.
*/
(*ctx->Driver.Viewport)( ctx, x, y, width, height );
}
}