/*
* Read R, G, B, A, RGB, L, or LA pixels.
*/
static void
read_rgba_pixels( struct gl_context *ctx,
GLint x, GLint y,
GLsizei width, GLsizei height,
GLenum format, GLenum type, GLvoid *pixels,
const struct gl_pixelstore_attrib *packing )
{
GLbitfield transferOps;
bool dst_is_integer, convert_rgb_to_lum, needs_rebase;
int dst_stride, src_stride, rb_stride;
uint32_t dst_format, src_format;
GLubyte *dst, *map;
mesa_format rb_format;
bool needs_rgba;
void *rgba, *src;
bool src_is_uint = false;
uint8_t rebase_swizzle[4];
struct gl_framebuffer *fb = ctx->ReadBuffer;
struct gl_renderbuffer *rb = fb->_ColorReadBuffer;
GLenum dstBaseFormat = _mesa_unpack_format_to_base_format(format);
if (!rb)
return;
transferOps = _mesa_get_readpixels_transfer_ops(ctx, rb->Format, format,
type, GL_FALSE);
/* Describe the dst format */
dst_is_integer = _mesa_is_enum_format_integer(format);
dst_stride = _mesa_image_row_stride(packing, width, format, type);
dst_format = _mesa_format_from_format_and_type(format, type);
convert_rgb_to_lum =
_mesa_need_rgb_to_luminance_conversion(rb->_BaseFormat, dstBaseFormat);
dst = (GLubyte *) _mesa_image_address2d(packing, pixels, width, height,
format, type, 0, 0);
/* Map the source render buffer */
ctx->Driver.MapRenderbuffer(ctx, rb, x, y, width, height, GL_MAP_READ_BIT,
&map, &rb_stride);
if (!map) {
_mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
return;
}
rb_format = _mesa_get_srgb_format_linear(rb->Format);
/*
* Depending on the base formats involved in the conversion we might need to
* rebase some values, so for these formats we compute a rebase swizzle.
*/
if (rb->_BaseFormat == GL_LUMINANCE || rb->_BaseFormat == GL_INTENSITY) {
needs_rebase = true;
rebase_swizzle[0] = MESA_FORMAT_SWIZZLE_X;
rebase_swizzle[1] = MESA_FORMAT_SWIZZLE_ZERO;
rebase_swizzle[2] = MESA_FORMAT_SWIZZLE_ZERO;
rebase_swizzle[3] = MESA_FORMAT_SWIZZLE_ONE;
} else if (rb->_BaseFormat == GL_LUMINANCE_ALPHA) {
needs_rebase = true;
rebase_swizzle[0] = MESA_FORMAT_SWIZZLE_X;
rebase_swizzle[1] = MESA_FORMAT_SWIZZLE_ZERO;
rebase_swizzle[2] = MESA_FORMAT_SWIZZLE_ZERO;
rebase_swizzle[3] = MESA_FORMAT_SWIZZLE_W;
} else if (_mesa_get_format_base_format(rb_format) != rb->_BaseFormat) {
needs_rebase =
_mesa_compute_rgba2base2rgba_component_mapping(rb->_BaseFormat,
rebase_swizzle);
} else {
needs_rebase = false;
}
/* Since _mesa_format_convert does not handle transferOps we need to handle
* them before we call the function. This requires to convert to RGBA float
* first so we can call _mesa_apply_rgba_transfer_ops. If the dst format is
* integer transferOps do not apply.
*
* Converting to luminance also requires converting to RGBA first, so we can
* then compute luminance values as L=R+G+B. Notice that this is different
* from GetTexImage, where we compute L=R.
*/
assert(!transferOps || (transferOps && !dst_is_integer));
needs_rgba = transferOps || convert_rgb_to_lum;
rgba = NULL;
if (needs_rgba) {
uint32_t rgba_format;
int rgba_stride;
bool need_convert;
/* Convert to RGBA float or int/uint depending on the type of the src */
if (dst_is_integer) {
src_is_uint = _mesa_is_format_unsigned(rb_format);
if (src_is_uint) {
rgba_format = RGBA32_UINT;
rgba_stride = width * 4 * sizeof(GLuint);
} else {
rgba_format = RGBA32_INT;
rgba_stride = width * 4 * sizeof(GLint);
}
} else {
rgba_format = RGBA32_FLOAT;
rgba_stride = width * 4 * sizeof(GLfloat);
}
/* If we are lucky and the dst format matches the RGBA format we need to
* convert to, then we can convert directly into the dst buffer and avoid
* the final conversion/copy from the rgba buffer to the dst buffer.
*/
if (dst_format == rgba_format &&
dst_stride == rgba_stride) {
need_convert = false;
rgba = dst;
} else {
need_convert = true;
rgba = malloc(height * rgba_stride);
if (!rgba) {
_mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
goto done_unmap;
}
}
/* Convert to RGBA now */
_mesa_format_convert(rgba, rgba_format, rgba_stride,
map, rb_format, rb_stride,
width, height,
needs_rebase ? rebase_swizzle : NULL);
/* Handle transfer ops if necessary */
if (transferOps)
_mesa_apply_rgba_transfer_ops(ctx, transferOps, width * height, rgba);
/* If we had to rebase, we have already taken care of that */
needs_rebase = false;
/* If we were lucky and our RGBA conversion matches the dst format, then
* we are done.
*/
if (!need_convert)
goto done_swap;
/* Otherwise, we need to convert from RGBA to dst next */
src = rgba;
src_format = rgba_format;
src_stride = rgba_stride;
} else {
/* No RGBA conversion needed, convert directly to dst */
src = map;
src_format = rb_format;
src_stride = rb_stride;
}
/* Do the conversion.
*
* If the dst format is Luminance, we need to do the conversion by computing
* L=R+G+B values.
*/
if (!convert_rgb_to_lum) {
_mesa_format_convert(dst, dst_format, dst_stride,
src, src_format, src_stride,
width, height,
needs_rebase ? rebase_swizzle : NULL);
} else if (!dst_is_integer) {
/* Compute float Luminance values from RGBA float */
int luminance_stride, luminance_bytes;
void *luminance;
uint32_t luminance_format;
luminance_stride = width * sizeof(GL_FLOAT);
if (format == GL_LUMINANCE_ALPHA)
luminance_stride *= 2;
luminance_bytes = height * luminance_stride;
luminance = malloc(luminance_bytes);
if (!luminance) {
_mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
free(rgba);
goto done_unmap;
}
_mesa_pack_luminance_from_rgba_float(width * height, src,
luminance, format, transferOps);
/* Convert from Luminance float to dst (this will hadle type conversion
* from float to the type of dst if necessary)
*/
luminance_format = _mesa_format_from_format_and_type(format, GL_FLOAT);
_mesa_format_convert(dst, dst_format, dst_stride,
luminance, luminance_format, luminance_stride,
width, height, NULL);
free(luminance);
} else {
_mesa_pack_luminance_from_rgba_integer(width * height, src, !src_is_uint,
dst, format, type);
}
if (rgba)
free(rgba);
done_swap:
/* Handle byte swapping if required */
if (packing->SwapBytes) {
_mesa_swap_bytes_2d_image(format, type, packing,
width, height, dst, dst);
}
done_unmap:
ctx->Driver.UnmapRenderbuffer(ctx, rb);
}
bool
_mesa_meta_pbo_GetTexSubImage(struct gl_context *ctx, GLuint dims,
struct gl_texture_image *tex_image,
int xoffset, int yoffset, int zoffset,
int width, int height, int depth,
GLenum format, GLenum type, const void *pixels,
const struct gl_pixelstore_attrib *packing)
{
struct gl_buffer_object *pbo = NULL;
GLuint pbo_tex = 0;
struct gl_framebuffer *readFb;
struct gl_framebuffer *drawFb;
int image_height;
struct gl_texture_image *pbo_tex_image;
struct gl_renderbuffer *rb = NULL;
GLenum dstBaseFormat = _mesa_unpack_format_to_base_format(format);
GLenum status, src_base_format;
bool success = false, clear_channels_to_zero = false;
float save_clear_color[4];
int z;
if (!_mesa_is_bufferobj(packing->BufferObj))
return false;
if (format == GL_DEPTH_COMPONENT ||
format == GL_DEPTH_STENCIL ||
format == GL_STENCIL_INDEX ||
format == GL_COLOR_INDEX)
return false;
/* Don't use meta path for readpixels in below conditions. */
if (!tex_image) {
rb = ctx->ReadBuffer->_ColorReadBuffer;
/* _mesa_get_readpixels_transfer_ops() includes the cases of read
* color clamping along with the ctx->_ImageTransferState.
*/
if (_mesa_get_readpixels_transfer_ops(ctx, rb->Format, format,
type, GL_FALSE))
return false;
if (_mesa_need_rgb_to_luminance_conversion(rb->_BaseFormat,
dstBaseFormat))
return false;
/* This function rely on BlitFramebuffer to fill in the pixel data for
* ReadPixels. But, BlitFrameBuffer doesn't support signed to unsigned
* or unsigned to signed integer conversions. OpenGL spec expects an
* invalid operation in that case.
*/
if (need_signed_unsigned_int_conversion(rb->Format, format, type))
return false;
} else {
if (need_signed_unsigned_int_conversion(tex_image->TexFormat, format, type))
return false;
}
/* For arrays, use a tall (height * depth) 2D texture but taking into
* account the inter-image padding specified with the image height packing
* property.
*/
image_height = packing->ImageHeight == 0 ? height : packing->ImageHeight;
_mesa_meta_begin(ctx, ~(MESA_META_PIXEL_TRANSFER |
MESA_META_PIXEL_STORE));
pbo_tex_image = create_texture_for_pbo(ctx, false, GL_PIXEL_PACK_BUFFER,
dims, width, height, depth,
format, type, pixels, packing,
&pbo, &pbo_tex);
if (!pbo_tex_image) {
_mesa_meta_end(ctx);
return false;
}
/* GL_CLAMP_FRAGMENT_COLOR doesn't affect ReadPixels and GettexImage */
if (ctx->Extensions.ARB_color_buffer_float)
_mesa_ClampColor(GL_CLAMP_FRAGMENT_COLOR, GL_FALSE);
readFb = ctx->Driver.NewFramebuffer(ctx, 0xDEADBEEF);
if (readFb == NULL)
goto fail;
drawFb = ctx->Driver.NewFramebuffer(ctx, 0xDEADBEEF);
if (drawFb == NULL)
goto fail;
if (tex_image && tex_image->TexObject->Target == GL_TEXTURE_1D_ARRAY) {
assert(depth == 1);
assert(zoffset == 0);
depth = height;
height = 1;
image_height = 1;
zoffset = yoffset;
yoffset = 0;
}
/* If we were given a texture, bind it to the read framebuffer. If not,
* we're doing a ReadPixels and we should just use whatever framebuffer
* the client has bound.
*/
_mesa_bind_framebuffers(ctx, drawFb, tex_image ? readFb : ctx->ReadBuffer);
if (tex_image) {
_mesa_meta_framebuffer_texture_image(ctx, ctx->ReadBuffer,
GL_COLOR_ATTACHMENT0,
tex_image, zoffset);
/* If this passes on the first layer it should pass on the others */
status = _mesa_check_framebuffer_status(ctx, ctx->ReadBuffer);
if (status != GL_FRAMEBUFFER_COMPLETE)
goto fail;
} else {
assert(depth == 1);
}
_mesa_meta_framebuffer_texture_image(ctx, ctx->DrawBuffer,
GL_COLOR_ATTACHMENT0,
pbo_tex_image, 0);
/* If this passes on the first layer it should pass on the others */
status = _mesa_check_framebuffer_status(ctx, ctx->DrawBuffer);
if (status != GL_FRAMEBUFFER_COMPLETE)
goto fail;
/* Explicitly disable sRGB encoding */
ctx->DrawBuffer->Visual.sRGBCapable = false;
_mesa_update_state(ctx);
if (_mesa_meta_BlitFramebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer,
xoffset, yoffset,
xoffset + width, yoffset + height,
0, 0, width, height,
GL_COLOR_BUFFER_BIT, GL_NEAREST))
goto fail;
src_base_format = tex_image ?
tex_image->_BaseFormat :
ctx->ReadBuffer->_ColorReadBuffer->_BaseFormat;
/* Depending on the base formats involved we might need to rebase some
* values. For example if we download from a Luminance format to RGBA
* format, we want G=0 and B=0.
*/
clear_channels_to_zero =
_mesa_need_luminance_to_rgb_conversion(src_base_format,
pbo_tex_image->_BaseFormat);
if (clear_channels_to_zero) {
memcpy(save_clear_color, ctx->Color.ClearColor.f, 4 * sizeof(float));
/* Clear the Green, Blue channels. */
_mesa_ColorMask(GL_FALSE, GL_TRUE, GL_TRUE,
src_base_format != GL_LUMINANCE_ALPHA);
_mesa_ClearColor(0.0, 0.0, 0.0, 1.0);
_mesa_Clear(GL_COLOR_BUFFER_BIT);
}
for (z = 1; z < depth; z++) {
_mesa_meta_framebuffer_texture_image(ctx, ctx->ReadBuffer,
GL_COLOR_ATTACHMENT0,
tex_image, zoffset + z);
_mesa_update_state(ctx);
_mesa_meta_BlitFramebuffer(ctx, ctx->ReadBuffer, ctx->DrawBuffer,
xoffset, yoffset,
xoffset + width, yoffset + height,
0, z * image_height,
width, z * image_height + height,
GL_COLOR_BUFFER_BIT, GL_NEAREST);
if (clear_channels_to_zero)
_mesa_Clear(GL_COLOR_BUFFER_BIT);
}
/* Unmask the color channels and restore the saved clear color values. */
if (clear_channels_to_zero) {
_mesa_ColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
_mesa_ClearColor(save_clear_color[0], save_clear_color[1],
save_clear_color[2], save_clear_color[3]);
}
success = true;
fail:
_mesa_reference_framebuffer(&drawFb, NULL);
_mesa_reference_framebuffer(&readFb, NULL);
_mesa_DeleteTextures(1, &pbo_tex);
_mesa_reference_buffer_object(ctx, &pbo, NULL);
_mesa_meta_end(ctx);
return success;
}
