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/*
* Mesa 3-D graphics library
* Version: 6.5.1
*
* Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
* AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
/**
* Functions for allocating/managing framebuffers and renderbuffers.
* Also, routines for reading/writing renderbuffer data as ubytes,
* ushorts, uints, etc.
*/
#include "glheader.h"
#include "imports.h"
#include "context.h"
#include "depthstencil.h"
#include "mtypes.h"
#include "fbobject.h"
#include "framebuffer.h"
#include "renderbuffer.h"
/**
* Compute/set the _DepthMax field for the given framebuffer.
* This value depends on the Z buffer resolution.
*/
static void
compute_depth_max(struct gl_framebuffer *fb)
{
if (fb->Visual.depthBits == 0) {
/* Special case. Even if we don't have a depth buffer we need
* good values for DepthMax for Z vertex transformation purposes
* and for per-fragment fog computation.
*/
fb->_DepthMax = (1 << 16) - 1;
}
else if (fb->Visual.depthBits < 32) {
fb->_DepthMax = (1 << fb->Visual.depthBits) - 1;
}
else {
/* Special case since shift values greater than or equal to the
* number of bits in the left hand expression's type are undefined.
*/
fb->_DepthMax = 0xffffffff;
}
fb->_DepthMaxF = (GLfloat) fb->_DepthMax;
fb->_MRD = 1.0; /* Minimum resolvable depth value, for polygon offset */
}
/**
* Set the framebuffer's _DepthBuffer field, taking care of
* reference counts, etc.
*/
static void
set_depth_renderbuffer(struct gl_framebuffer *fb,
struct gl_renderbuffer *rb)
{
if (fb->_DepthBuffer) {
_mesa_dereference_renderbuffer(&fb->_DepthBuffer);
}
fb->_DepthBuffer = rb;
if (rb) {
rb->RefCount++;
}
}
/**
* Set the framebuffer's _StencilBuffer field, taking care of
* reference counts, etc.
*/
static void
set_stencil_renderbuffer(struct gl_framebuffer *fb,
struct gl_renderbuffer *rb)
{
if (fb->_StencilBuffer) {
_mesa_dereference_renderbuffer(&fb->_StencilBuffer);
}
fb->_StencilBuffer = rb;
if (rb) {
rb->RefCount++;
}
}
/**
* Create and initialize a gl_framebuffer object.
* This is intended for creating _window_system_ framebuffers, not generic
* framebuffer objects ala GL_EXT_framebuffer_object.
*
* \sa _mesa_new_framebuffer
*/
struct gl_framebuffer *
_mesa_create_framebuffer(const GLvisual *visual)
{
struct gl_framebuffer *fb = CALLOC_STRUCT(gl_framebuffer);
assert(visual);
if (fb) {
_mesa_initialize_framebuffer(fb, visual);
}
return fb;
}
/**
* Allocate a new gl_framebuffer object.
* This is the default function for ctx->Driver.NewFramebuffer().
* This is for allocating user-created framebuffers, not window-system
* framebuffers!
* \sa _mesa_create_framebuffer
*/
struct gl_framebuffer *
_mesa_new_framebuffer(GLcontext *ctx, GLuint name)
{
struct gl_framebuffer *fb;
(void) ctx;
assert(name != 0);
fb = CALLOC_STRUCT(gl_framebuffer);
if (fb) {
fb->Name = name;
fb->RefCount = 1;
fb->ColorDrawBuffer[0] = GL_COLOR_ATTACHMENT0_EXT;
fb->_ColorDrawBufferMask[0] = BUFFER_BIT_COLOR0;
fb->ColorReadBuffer = GL_COLOR_ATTACHMENT0_EXT;
fb->_ColorReadBufferIndex = BUFFER_COLOR0;
fb->Delete = _mesa_destroy_framebuffer;
}
return fb;
}
/**
* Initialize a gl_framebuffer object. Typically used to initialize
* window system-created framebuffers, not user-created framebuffers.
* \sa _mesa_create_framebuffer
*/
void
_mesa_initialize_framebuffer(struct gl_framebuffer *fb, const GLvisual *visual)
{
assert(fb);
assert(visual);
_mesa_bzero(fb, sizeof(struct gl_framebuffer));
_glthread_INIT_MUTEX(fb->Mutex);
fb->RefCount = 1;
/* save the visual */
fb->Visual = *visual;
/* Init glRead/DrawBuffer state */
if (visual->doubleBufferMode) {
fb->ColorDrawBuffer[0] = GL_BACK;
fb->_ColorDrawBufferMask[0] = BUFFER_BIT_BACK_LEFT;
fb->ColorReadBuffer = GL_BACK;
fb->_ColorReadBufferIndex = BUFFER_BACK_LEFT;
}
else {
fb->ColorDrawBuffer[0] = GL_FRONT;
fb->_ColorDrawBufferMask[0] = BUFFER_BIT_FRONT_LEFT;
fb->ColorReadBuffer = GL_FRONT;
fb->_ColorReadBufferIndex = BUFFER_FRONT_LEFT;
}
fb->Delete = _mesa_destroy_framebuffer;
fb->_Status = GL_FRAMEBUFFER_COMPLETE_EXT;
compute_depth_max(fb);
}
/**
* Deallocate buffer and everything attached to it.
* Typically called via the gl_framebuffer->Delete() method.
*/
void
_mesa_destroy_framebuffer(struct gl_framebuffer *fb)
{
if (fb) {
_mesa_free_framebuffer_data(fb);
_mesa_free(fb);
}
}
/**
* Free all the data hanging off the given gl_framebuffer, but don't free
* the gl_framebuffer object itself.
*/
void
_mesa_free_framebuffer_data(struct gl_framebuffer *fb)
{
GLuint i;
assert(fb);
assert(fb->RefCount == 0);
_glthread_DESTROY_MUTEX(fb->Mutex);
for (i = 0; i < BUFFER_COUNT; i++) {
struct gl_renderbuffer_attachment *att = &fb->Attachment[i];
if (att->Renderbuffer) {
struct gl_renderbuffer *rb = att->Renderbuffer;
/* remove framebuffer's reference to renderbuffer */
_mesa_dereference_renderbuffer(&rb);
if (rb && rb->Name == 0) {
/* delete window system renderbuffer */
_mesa_dereference_renderbuffer(&rb);
}
}
att->Type = GL_NONE;
att->Renderbuffer = NULL;
}
/* unbind depth/stencil to decr ref counts */
set_depth_renderbuffer(fb, NULL);
set_stencil_renderbuffer(fb, NULL);
}
/**
* Decrement the reference count on a framebuffer and delete it when
* the refcount hits zero.
* Note: we pass the address of a pointer and set it to NULL if we delete it.
*/
void
_mesa_dereference_framebuffer(struct gl_framebuffer **fb)
{
GLboolean deleteFlag = GL_FALSE;
_glthread_LOCK_MUTEX((*fb)->Mutex);
{
ASSERT((*fb)->RefCount > 0);
(*fb)->RefCount--;
deleteFlag = ((*fb)->RefCount == 0);
}
_glthread_UNLOCK_MUTEX((*fb)->Mutex);
if (deleteFlag) {
(*fb)->Delete(*fb);
*fb = NULL;
}
}
/**
* Resize the given framebuffer's renderbuffers to the new width and height.
* This should only be used for window-system framebuffers, not
* user-created renderbuffers (i.e. made with GL_EXT_framebuffer_object).
* This will typically be called via ctx->Driver.ResizeBuffers() or directly
* from a device driver.
*
* \note it's possible for ctx to be null since a window can be resized
* without a currently bound rendering context.
*/
void
_mesa_resize_framebuffer(GLcontext *ctx, struct gl_framebuffer *fb,
GLuint width, GLuint height)
{
GLuint i;
/* XXX I think we could check if the size is not changing
* and return early.
*/
/* For window system framebuffers, Name is zero */
assert(fb->Name == 0);
for (i = 0; i < BUFFER_COUNT; i++) {
struct gl_renderbuffer_attachment *att = &fb->Attachment[i];
if (att->Type == GL_RENDERBUFFER_EXT && att->Renderbuffer) {
struct gl_renderbuffer *rb = att->Renderbuffer;
/* only resize if size is changing */
if (rb->Width != width || rb->Height != height) {
/* could just as well pass rb->_ActualFormat here */
if (rb->AllocStorage(ctx, rb, rb->InternalFormat, width, height)) {
ASSERT(rb->Width == width);
ASSERT(rb->Height == height);
}
else {
_mesa_error(ctx, GL_OUT_OF_MEMORY, "Resizing framebuffer");
/* no return */
}
}
}
}
if (fb->_DepthBuffer) {
struct gl_renderbuffer *rb = fb->_DepthBuffer;
if (rb->Width != width || rb->Height != height) {
if (!rb->AllocStorage(ctx, rb, rb->InternalFormat, width, height)) {
_mesa_error(ctx, GL_OUT_OF_MEMORY, "Resizing framebuffer");
}
}
}
if (fb->_StencilBuffer) {
struct gl_renderbuffer *rb = fb->_StencilBuffer;
if (rb->Width != width || rb->Height != height) {
if (!rb->AllocStorage(ctx, rb, rb->InternalFormat, width, height)) {
_mesa_error(ctx, GL_OUT_OF_MEMORY, "Resizing framebuffer");
}
}
}
fb->Width = width;
fb->Height = height;
if (ctx) {
/* update scissor / window bounds */
_mesa_update_draw_buffer_bounds(ctx);
/* Signal new buffer state so that swrast will update its clipping
* info (the CLIP_BIT flag).
*/
ctx->NewState |= _NEW_BUFFERS;
}
}
/**
* Examine all the framebuffer's renderbuffers to update the Width/Height
* fields of the framebuffer. If we have renderbuffers with different
* sizes, set the framebuffer's width and height to zero.
* Note: this is only intended for user-created framebuffers, not
* window-system framebuffes.
*/
static void
update_framebuffer_size(struct gl_framebuffer *fb)
{
GLboolean haveSize = GL_FALSE;
GLuint i;
/* user-created framebuffers only */
assert(fb->Name);
for (i = 0; i < BUFFER_COUNT; i++) {
struct gl_renderbuffer_attachment *att = &fb->Attachment[i];
const struct gl_renderbuffer *rb = att->Renderbuffer;
if (rb) {
if (haveSize) {
if (rb->Width != fb->Width && rb->Height != fb->Height) {
/* size mismatch! */
fb->Width = 0;
fb->Height = 0;
return;
}
}
else {
fb->Width = rb->Width;
fb->Height = rb->Height;
haveSize = GL_TRUE;
}
}
}
}
/**
* Update the context's current drawing buffer's Xmin, Xmax, Ymin, Ymax fields.
* These values are computed from the buffer's width and height and
* the scissor box, if it's enabled.
* \param ctx the GL context.
*/
void
_mesa_update_draw_buffer_bounds(GLcontext *ctx)
{
struct gl_framebuffer *buffer = ctx->DrawBuffer;
if (!buffer)
return;
if (buffer->Name) {
/* user-created framebuffer size depends on the renderbuffers */
update_framebuffer_size(buffer);
}
buffer->_Xmin = 0;
buffer->_Ymin = 0;
buffer->_Xmax = buffer->Width;
buffer->_Ymax = buffer->Height;
if (ctx->Scissor.Enabled) {
if (ctx->Scissor.X > buffer->_Xmin) {
buffer->_Xmin = ctx->Scissor.X;
}
if (ctx->Scissor.Y > buffer->_Ymin) {
buffer->_Ymin = ctx->Scissor.Y;
}
if (ctx->Scissor.X + ctx->Scissor.Width < buffer->_Xmax) {
buffer->_Xmax = ctx->Scissor.X + ctx->Scissor.Width;
}
if (ctx->Scissor.Y + ctx->Scissor.Height < buffer->_Ymax) {
buffer->_Ymax = ctx->Scissor.Y + ctx->Scissor.Height;
}
/* finally, check for empty region */
if (buffer->_Xmin > buffer->_Xmax) {
buffer->_Xmin = buffer->_Xmax;
}
if (buffer->_Ymin > buffer->_Ymax) {
buffer->_Ymin = buffer->_Ymax;
}
}
ASSERT(buffer->_Xmin <= buffer->_Xmax);
ASSERT(buffer->_Ymin <= buffer->_Ymax);
}
/**
* The glGet queries of the framebuffer red/green/blue size, stencil size,
* etc. are satisfied by the fields of ctx->DrawBuffer->Visual. These can
* change depending on the renderbuffer bindings. This function updates
* the given framebuffer's Visual from the current renderbuffer bindings.
*
* This may apply to user-created framebuffers or window system framebuffers.
*
* Also note: ctx->DrawBuffer->Visual.depthBits might not equal
* ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer.DepthBits.
* The former one is used to convert floating point depth values into
* integer Z values.
*/
void
_mesa_update_framebuffer_visual(struct gl_framebuffer *fb)
{
GLuint i;
_mesa_bzero(&fb->Visual, sizeof(fb->Visual));
fb->Visual.rgbMode = GL_TRUE; /* assume this */
#if 0 /* this _might_ be needed */
if (fb->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
/* leave visual fields zero'd */
return;
}
#endif
/* find first RGB or CI renderbuffer */
for (i = 0; i < BUFFER_COUNT; i++) {
if (fb->Attachment[i].Renderbuffer) {
const struct gl_renderbuffer *rb = fb->Attachment[i].Renderbuffer;
if (rb->_BaseFormat == GL_RGBA || rb->_BaseFormat == GL_RGB) {
fb->Visual.redBits = rb->RedBits;
fb->Visual.greenBits = rb->GreenBits;
fb->Visual.blueBits = rb->BlueBits;
fb->Visual.alphaBits = rb->AlphaBits;
fb->Visual.rgbBits = fb->Visual.redBits
+ fb->Visual.greenBits + fb->Visual.blueBits;
fb->Visual.floatMode = GL_FALSE;
break;
}
else if (rb->_BaseFormat == GL_COLOR_INDEX) {
fb->Visual.indexBits = rb->IndexBits;
fb->Visual.rgbMode = GL_FALSE;
break;
}
}
}
if (fb->Attachment[BUFFER_DEPTH].Renderbuffer) {
fb->Visual.haveDepthBuffer = GL_TRUE;
fb->Visual.depthBits
= fb->Attachment[BUFFER_DEPTH].Renderbuffer->DepthBits;
}
if (fb->Attachment[BUFFER_STENCIL].Renderbuffer) {
fb->Visual.haveStencilBuffer = GL_TRUE;
fb->Visual.stencilBits
= fb->Attachment[BUFFER_STENCIL].Renderbuffer->StencilBits;
}
if (fb->Attachment[BUFFER_ACCUM].Renderbuffer) {
fb->Visual.haveAccumBuffer = GL_TRUE;
fb->Visual.accumRedBits
= fb->Attachment[BUFFER_DEPTH].Renderbuffer->RedBits;
fb->Visual.accumGreenBits
= fb->Attachment[BUFFER_DEPTH].Renderbuffer->GreenBits;
fb->Visual.accumBlueBits
= fb->Attachment[BUFFER_DEPTH].Renderbuffer->BlueBits;
fb->Visual.accumAlphaBits
= fb->Attachment[BUFFER_DEPTH].Renderbuffer->AlphaBits;
}
compute_depth_max(fb);
}
/**
* Update the framebuffer's _DepthBuffer field using the renderbuffer
* found at the given attachment index.
*
* If that attachment points to a combined GL_DEPTH_STENCIL renderbuffer,
* create and install a depth wrapper/adaptor.
*
* \param fb the framebuffer whose _DepthBuffer field to update
* \param attIndex indicates the renderbuffer to possibly wrap
*/
void
_mesa_update_depth_buffer(GLcontext *ctx,
struct gl_framebuffer *fb,
GLuint attIndex)
{
struct gl_renderbuffer *depthRb;
/* only one possiblity for now */
ASSERT(attIndex == BUFFER_DEPTH);
depthRb = fb->Attachment[attIndex].Renderbuffer;
if (depthRb && depthRb->_ActualFormat == GL_DEPTH24_STENCIL8_EXT) {
/* The attached depth buffer is a GL_DEPTH_STENCIL renderbuffer */
if (!fb->_DepthBuffer
|| fb->_DepthBuffer->Wrapped != depthRb
|| fb->_DepthBuffer->_BaseFormat != GL_DEPTH_COMPONENT) {
/* need to update wrapper */
struct gl_renderbuffer *wrapper
= _mesa_new_z24_renderbuffer_wrapper(ctx, depthRb);
set_depth_renderbuffer(fb, wrapper);
ASSERT(fb->_DepthBuffer->Wrapped == depthRb);
}
}
else {
/* depthRb may be null */
set_depth_renderbuffer(fb, depthRb);
}
}
/**
* Update the framebuffer's _StencilBuffer field using the renderbuffer
* found at the given attachment index.
*
* If that attachment points to a combined GL_DEPTH_STENCIL renderbuffer,
* create and install a stencil wrapper/adaptor.
*
* \param fb the framebuffer whose _StencilBuffer field to update
* \param attIndex indicates the renderbuffer to possibly wrap
*/
void
_mesa_update_stencil_buffer(GLcontext *ctx,
struct gl_framebuffer *fb,
GLuint attIndex)
{
struct gl_renderbuffer *stencilRb;
ASSERT(attIndex == BUFFER_DEPTH ||
attIndex == BUFFER_STENCIL);
stencilRb = fb->Attachment[attIndex].Renderbuffer;
if (stencilRb && stencilRb->_ActualFormat == GL_DEPTH24_STENCIL8_EXT) {
/* The attached stencil buffer is a GL_DEPTH_STENCIL renderbuffer */
if (!fb->_StencilBuffer
|| fb->_StencilBuffer->Wrapped != stencilRb
|| fb->_StencilBuffer->_BaseFormat != GL_STENCIL_INDEX) {
/* need to update wrapper */
struct gl_renderbuffer *wrapper
= _mesa_new_s8_renderbuffer_wrapper(ctx, stencilRb);
set_stencil_renderbuffer(fb, wrapper);
ASSERT(fb->_StencilBuffer->Wrapped == stencilRb);
}
}
else {
/* stencilRb may be null */
set_stencil_renderbuffer(fb, stencilRb);
}
}
/**
* Update the list of color drawing renderbuffer pointers.
* Later, when we're rendering we'll loop from 0 to _NumColorDrawBuffers
* writing colors.
*/
static void
update_color_draw_buffers(GLcontext *ctx, struct gl_framebuffer *fb)
{
GLuint output;
/*
* Fragment programs can write to multiple colorbuffers with
* the GL_ARB_draw_buffers extension.
*/
for (output = 0; output < ctx->Const.MaxDrawBuffers; output++) {
GLbitfield bufferMask = fb->_ColorDrawBufferMask[output];
GLuint count = 0;
GLuint i;
if (!fb->DeletePending) {
/* We need the inner loop here because glDrawBuffer(GL_FRONT_AND_BACK)
* can specify writing to two or four color buffers (for example).
*/
for (i = 0; bufferMask && i < BUFFER_COUNT; i++) {
const GLuint bufferBit = 1 << i;
if (bufferBit & bufferMask) {
struct gl_renderbuffer *rb = fb->Attachment[i].Renderbuffer;
if (rb) {
fb->_ColorDrawBuffers[output][count] = rb;
count++;
}
else {
/*
_mesa_warning(ctx, "DrawBuffer names a missing buffer!\n");
*/
}
bufferMask &= ~bufferBit;
}
}
}
fb->_NumColorDrawBuffers[output] = count;
}
}
/**
* Update the color read renderbuffer pointer.
* Unlike the DrawBuffer, we can only read from one (or zero) color buffers.
*/
static void
update_color_read_buffer(GLcontext *ctx, struct gl_framebuffer *fb)
{
(void) ctx;
if (fb->_ColorReadBufferIndex == -1 || fb->DeletePending) {
fb->_ColorReadBuffer = NULL; /* legal! */
}
else {
ASSERT(fb->_ColorReadBufferIndex >= 0);
ASSERT(fb->_ColorReadBufferIndex < BUFFER_COUNT);
fb->_ColorReadBuffer
= fb->Attachment[fb->_ColorReadBufferIndex].Renderbuffer;
}
}
/**
* Update state related to the current draw/read framebuffers.
* Specifically, update these framebuffer fields:
* _ColorDrawBuffers
* _NumColorDrawBuffers
* _ColorReadBuffer
* _DepthBuffer
* _StencilBuffer
* If the current framebuffer is user-created, make sure it's complete.
* The following functions can effect this state: glReadBuffer,
* glDrawBuffer, glDrawBuffersARB, glFramebufferRenderbufferEXT,
* glRenderbufferStorageEXT.
*/
void
_mesa_update_framebuffer(GLcontext *ctx)
{
struct gl_framebuffer *fb = ctx->DrawBuffer;
/* Completeness only matters for user-created framebuffers */
if (fb->Name != 0) {
_mesa_test_framebuffer_completeness(ctx, fb);
_mesa_update_framebuffer_visual(fb);
}
update_color_draw_buffers(ctx, fb);
update_color_read_buffer(ctx, fb);
_mesa_update_depth_buffer(ctx, fb, BUFFER_DEPTH);
_mesa_update_stencil_buffer(ctx, fb, BUFFER_STENCIL);
compute_depth_max(fb);
}
/**
* Check if the renderbuffer for a read operation (glReadPixels, glCopyPixels,
* glCopyTex[Sub]Image, etc. exists.
* \param format a basic image format such as GL_RGB, GL_RGBA, GL_ALPHA,
* GL_DEPTH_COMPONENT, etc. or GL_COLOR, GL_DEPTH, GL_STENCIL.
* \return GL_TRUE if buffer exists, GL_FALSE otherwise
*/
GLboolean
_mesa_source_buffer_exists(GLcontext *ctx, GLenum format)
{
const struct gl_renderbuffer_attachment *att
= ctx->ReadBuffer->Attachment;
if (ctx->ReadBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
return GL_FALSE;
}
switch (format) {
case GL_COLOR:
case GL_RED:
case GL_GREEN:
case GL_BLUE:
case GL_ALPHA:
case GL_LUMINANCE:
case GL_LUMINANCE_ALPHA:
case GL_INTENSITY:
case GL_RGB:
case GL_BGR:
case GL_RGBA:
case GL_BGRA:
case GL_ABGR_EXT:
case GL_COLOR_INDEX:
if (ctx->ReadBuffer->_ColorReadBuffer == NULL) {
return GL_FALSE;
}
/* XXX enable this post 6.5 release:
ASSERT(ctx->ReadBuffer->_ColorReadBuffer->RedBits > 0 ||
ctx->ReadBuffer->_ColorReadBuffer->IndexBits > 0);
*/
break;
case GL_DEPTH:
case GL_DEPTH_COMPONENT:
if (!att[BUFFER_DEPTH].Renderbuffer) {
return GL_FALSE;
}
ASSERT(att[BUFFER_DEPTH].Renderbuffer->DepthBits > 0);
break;
case GL_STENCIL:
case GL_STENCIL_INDEX:
if (!att[BUFFER_STENCIL].Renderbuffer) {
return GL_FALSE;
}
ASSERT(att[BUFFER_STENCIL].Renderbuffer->StencilBits > 0);
break;
case GL_DEPTH_STENCIL_EXT:
if (!att[BUFFER_DEPTH].Renderbuffer ||
!att[BUFFER_STENCIL].Renderbuffer) {
return GL_FALSE;
}
ASSERT(att[BUFFER_DEPTH].Renderbuffer->DepthBits > 0);
ASSERT(att[BUFFER_STENCIL].Renderbuffer->StencilBits > 0);
break;
default:
_mesa_problem(ctx,
"Unexpected format 0x%x in _mesa_source_buffer_exists",
format);
return GL_FALSE;
}
/* OK */
return GL_TRUE;
}
/**
* As above, but for drawing operations.
* XXX code do some code merging w/ above function.
*/
GLboolean
_mesa_dest_buffer_exists(GLcontext *ctx, GLenum format)
{
const struct gl_renderbuffer_attachment *att
= ctx->ReadBuffer->Attachment;
if (ctx->DrawBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
return GL_FALSE;
}
switch (format) {
case GL_COLOR:
case GL_RED:
case GL_GREEN:
case GL_BLUE:
case GL_ALPHA:
case GL_LUMINANCE:
case GL_LUMINANCE_ALPHA:
case GL_INTENSITY:
case GL_RGB:
case GL_BGR:
case GL_RGBA:
case GL_BGRA:
case GL_ABGR_EXT:
case GL_COLOR_INDEX:
/* nothing special */
/* Could assert that colorbuffer has RedBits > 0 */
break;
case GL_DEPTH:
case GL_DEPTH_COMPONENT:
if (!att[BUFFER_DEPTH].Renderbuffer) {
return GL_FALSE;
}
ASSERT(att[BUFFER_DEPTH].Renderbuffer->DepthBits > 0);
break;
case GL_STENCIL:
case GL_STENCIL_INDEX:
if (!att[BUFFER_STENCIL].Renderbuffer) {
return GL_FALSE;
}
ASSERT(att[BUFFER_STENCIL].Renderbuffer->StencilBits > 0);
break;
case GL_DEPTH_STENCIL_EXT:
if (!att[BUFFER_DEPTH].Renderbuffer ||
!att[BUFFER_STENCIL].Renderbuffer) {
return GL_FALSE;
}
ASSERT(att[BUFFER_DEPTH].Renderbuffer->DepthBits > 0);
ASSERT(att[BUFFER_STENCIL].Renderbuffer->StencilBits > 0);
break;
default:
_mesa_problem(ctx,
"Unexpected format 0x%x in _mesa_source_buffer_exists",
format);
return GL_FALSE;
}
/* OK */
return GL_TRUE;
}
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