-/* $Id: buffers.c,v 1.20 2000/11/22 07:32:16 joukj Exp $ */
-
/*
* Mesa 3-D graphics library
- * Version: 3.5
+ * Version: 7.1
*
- * Copyright (C) 1999-2000 Brian Paul All Rights Reserved.
+ * Copyright (C) 1999-2007 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"),
*/
-#ifdef PC_HEADER
-#include "all.h"
-#else
+/**
+ * \file buffers.c
+ * glReadBuffer, DrawBuffer functions.
+ */
+
+
+
#include "glheader.h"
-#include "accum.h"
#include "buffers.h"
+#include "colormac.h"
#include "context.h"
-#include "depth.h"
#include "enums.h"
-#include "macros.h"
-#include "masking.h"
-#include "mem.h"
-#include "stencil.h"
+#include "fbobject.h"
#include "state.h"
-#include "mtypes.h"
-#include "swrast/swrast.h"
-#endif
+#define BAD_MASK ~0u
-void
-_mesa_ClearIndex( GLfloat c )
+
+/**
+ * Return bitmask of BUFFER_BIT_* flags indicating which color buffers are
+ * available to the rendering context (for drawing or reading).
+ * This depends on the type of framebuffer. For window system framebuffers
+ * we look at the framebuffer's visual. But for user-create framebuffers we
+ * look at the number of supported color attachments.
+ * \param fb the framebuffer to draw to, or read from
+ * \return bitmask of BUFFER_BIT_* flags
+ */
+static GLbitfield
+supported_buffer_bitmask(const GLcontext *ctx, const struct gl_framebuffer *fb)
{
- GET_CURRENT_CONTEXT(ctx);
- ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glClearIndex");
- ctx->Color.ClearIndex = (GLuint) c;
- ctx->NewState |= _NEW_COLOR;
+ GLbitfield mask = 0x0;
+
+ if (fb->Name > 0) {
+ /* A user-created renderbuffer */
+ GLuint i;
+ ASSERT(ctx->Extensions.EXT_framebuffer_object);
+ for (i = 0; i < ctx->Const.MaxColorAttachments; i++) {
+ mask |= (BUFFER_BIT_COLOR0 << i);
+ }
+ }
+ else {
+ /* A window system framebuffer */
+ GLint i;
+ mask = BUFFER_BIT_FRONT_LEFT; /* always have this */
+ if (fb->Visual.stereoMode) {
+ mask |= BUFFER_BIT_FRONT_RIGHT;
+ if (fb->Visual.doubleBufferMode) {
+ mask |= BUFFER_BIT_BACK_LEFT | BUFFER_BIT_BACK_RIGHT;
+ }
+ }
+ else if (fb->Visual.doubleBufferMode) {
+ mask |= BUFFER_BIT_BACK_LEFT;
+ }
- if (!ctx->Visual.RGBAflag) {
- /* it's OK to call glClearIndex in RGBA mode but it should be a NOP */
- (*ctx->Driver.ClearIndex)( ctx, ctx->Color.ClearIndex );
+ for (i = 0; i < fb->Visual.numAuxBuffers; i++) {
+ mask |= (BUFFER_BIT_AUX0 << i);
+ }
}
-}
+ return mask;
+}
-void
-_mesa_ClearColor( GLclampf red, GLclampf green,
- GLclampf blue, GLclampf alpha )
+/**
+ * Helper routine used by glDrawBuffer and glDrawBuffersARB.
+ * Given a GLenum naming one or more color buffers (such as
+ * GL_FRONT_AND_BACK), return the corresponding bitmask of BUFFER_BIT_* flags.
+ */
+static GLbitfield
+draw_buffer_enum_to_bitmask(GLenum buffer)
{
- GET_CURRENT_CONTEXT(ctx);
- ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glClearColor");
-
- ctx->Color.ClearColor[0] = CLAMP( red, 0.0F, 1.0F );
- ctx->Color.ClearColor[1] = CLAMP( green, 0.0F, 1.0F );
- ctx->Color.ClearColor[2] = CLAMP( blue, 0.0F, 1.0F );
- ctx->Color.ClearColor[3] = CLAMP( alpha, 0.0F, 1.0F );
- ctx->NewState |= _NEW_COLOR;
-
- if (ctx->Visual.RGBAflag) {
- GLchan r = (GLint) (ctx->Color.ClearColor[0] * CHAN_MAXF);
- GLchan g = (GLint) (ctx->Color.ClearColor[1] * CHAN_MAXF);
- GLchan b = (GLint) (ctx->Color.ClearColor[2] * CHAN_MAXF);
- GLchan a = (GLint) (ctx->Color.ClearColor[3] * CHAN_MAXF);
- (*ctx->Driver.ClearColor)( ctx, r, g, b, a );
+ switch (buffer) {
+ case GL_NONE:
+ return 0;
+ case GL_FRONT:
+ return BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_FRONT_RIGHT;
+ case GL_BACK:
+ return BUFFER_BIT_BACK_LEFT | BUFFER_BIT_BACK_RIGHT;
+ case GL_RIGHT:
+ return BUFFER_BIT_FRONT_RIGHT | BUFFER_BIT_BACK_RIGHT;
+ case GL_FRONT_RIGHT:
+ return BUFFER_BIT_FRONT_RIGHT;
+ case GL_BACK_RIGHT:
+ return BUFFER_BIT_BACK_RIGHT;
+ case GL_BACK_LEFT:
+ return BUFFER_BIT_BACK_LEFT;
+ case GL_FRONT_AND_BACK:
+ return BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT
+ | BUFFER_BIT_FRONT_RIGHT | BUFFER_BIT_BACK_RIGHT;
+ case GL_LEFT:
+ return BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT;
+ case GL_FRONT_LEFT:
+ return BUFFER_BIT_FRONT_LEFT;
+ case GL_AUX0:
+ return BUFFER_BIT_AUX0;
+ case GL_AUX1:
+ return BUFFER_BIT_AUX1;
+ case GL_AUX2:
+ return BUFFER_BIT_AUX2;
+ case GL_AUX3:
+ return BUFFER_BIT_AUX3;
+ case GL_COLOR_ATTACHMENT0_EXT:
+ return BUFFER_BIT_COLOR0;
+ case GL_COLOR_ATTACHMENT1_EXT:
+ return BUFFER_BIT_COLOR1;
+ case GL_COLOR_ATTACHMENT2_EXT:
+ return BUFFER_BIT_COLOR2;
+ case GL_COLOR_ATTACHMENT3_EXT:
+ return BUFFER_BIT_COLOR3;
+ case GL_COLOR_ATTACHMENT4_EXT:
+ return BUFFER_BIT_COLOR4;
+ case GL_COLOR_ATTACHMENT5_EXT:
+ return BUFFER_BIT_COLOR5;
+ case GL_COLOR_ATTACHMENT6_EXT:
+ return BUFFER_BIT_COLOR6;
+ case GL_COLOR_ATTACHMENT7_EXT:
+ return BUFFER_BIT_COLOR7;
+ default:
+ /* error */
+ return BAD_MASK;
}
}
+/**
+ * Helper routine used by glReadBuffer.
+ * Given a GLenum naming a color buffer, return the index of the corresponding
+ * renderbuffer (a BUFFER_* value).
+ * return -1 for an invalid buffer.
+ */
+static GLint
+read_buffer_enum_to_index(GLenum buffer)
+{
+ switch (buffer) {
+ case GL_FRONT:
+ return BUFFER_FRONT_LEFT;
+ case GL_BACK:
+ return BUFFER_BACK_LEFT;
+ case GL_RIGHT:
+ return BUFFER_FRONT_RIGHT;
+ case GL_FRONT_RIGHT:
+ return BUFFER_FRONT_RIGHT;
+ case GL_BACK_RIGHT:
+ return BUFFER_BACK_RIGHT;
+ case GL_BACK_LEFT:
+ return BUFFER_BACK_LEFT;
+ case GL_LEFT:
+ return BUFFER_FRONT_LEFT;
+ case GL_FRONT_LEFT:
+ return BUFFER_FRONT_LEFT;
+ case GL_AUX0:
+ return BUFFER_AUX0;
+ case GL_AUX1:
+ return BUFFER_AUX1;
+ case GL_AUX2:
+ return BUFFER_AUX2;
+ case GL_AUX3:
+ return BUFFER_AUX3;
+ case GL_COLOR_ATTACHMENT0_EXT:
+ return BUFFER_COLOR0;
+ case GL_COLOR_ATTACHMENT1_EXT:
+ return BUFFER_COLOR1;
+ case GL_COLOR_ATTACHMENT2_EXT:
+ return BUFFER_COLOR2;
+ case GL_COLOR_ATTACHMENT3_EXT:
+ return BUFFER_COLOR3;
+ case GL_COLOR_ATTACHMENT4_EXT:
+ return BUFFER_COLOR4;
+ case GL_COLOR_ATTACHMENT5_EXT:
+ return BUFFER_COLOR5;
+ case GL_COLOR_ATTACHMENT6_EXT:
+ return BUFFER_COLOR6;
+ case GL_COLOR_ATTACHMENT7_EXT:
+ return BUFFER_COLOR7;
+ default:
+ /* error */
+ return -1;
+ }
+}
-
-
-void
-_mesa_Clear( GLbitfield mask )
+/**
+ * Called by glDrawBuffer().
+ * Specify which renderbuffer(s) to draw into for the first color output.
+ * <buffer> can name zero, one, two or four renderbuffers!
+ * \sa _mesa_DrawBuffersARB
+ *
+ * \param buffer buffer token such as GL_LEFT or GL_FRONT_AND_BACK, etc.
+ *
+ * Note that the behaviour of this function depends on whether the
+ * current ctx->DrawBuffer is a window-system framebuffer (Name=0) or
+ * a user-created framebuffer object (Name!=0).
+ * In the former case, we update the per-context ctx->Color.DrawBuffer
+ * state var _and_ the FB's ColorDrawBuffer state.
+ * In the later case, we update the FB's ColorDrawBuffer state only.
+ *
+ * Furthermore, upon a MakeCurrent() or BindFramebuffer() call, if the
+ * new FB is a window system FB, we need to re-update the FB's
+ * ColorDrawBuffer state to match the context. This is handled in
+ * _mesa_update_framebuffer().
+ *
+ * See the GL_EXT_framebuffer_object spec for more info.
+ */
+void GLAPIENTRY
+_mesa_DrawBuffer(GLenum buffer)
{
+ GLbitfield destMask;
GET_CURRENT_CONTEXT(ctx);
- ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glClear");
-
- if (MESA_VERBOSE & VERBOSE_API)
- fprintf(stderr, "glClear 0x%x\n", mask);
+ ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* too complex... */
- if (ctx->NewState) {
- gl_update_state( ctx ); /* update _Xmin, etc */
+ if (MESA_VERBOSE & VERBOSE_API) {
+ _mesa_debug(ctx, "glDrawBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
}
- if (ctx->RenderMode==GL_RENDER) {
- const GLint x = ctx->DrawBuffer->_Xmin;
- const GLint y = ctx->DrawBuffer->_Ymin;
- const GLint height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
- const GLint width = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
- GLbitfield ddMask;
- GLbitfield newMask;
-
- /* don't clear depth buffer if depth writing disabled */
- if (!ctx->Depth.Mask)
- CLEAR_BITS(mask, GL_DEPTH_BUFFER_BIT);
-
- /* Build bitmask to send to driver Clear function */
- ddMask = mask & (GL_DEPTH_BUFFER_BIT |
- GL_STENCIL_BUFFER_BIT |
- GL_ACCUM_BUFFER_BIT);
- if (mask & GL_COLOR_BUFFER_BIT) {
- ddMask |= ctx->Color.DrawDestMask;
+ if (buffer == GL_NONE) {
+ destMask = 0x0;
+ }
+ else {
+ const GLbitfield supportedMask
+ = supported_buffer_bitmask(ctx, ctx->DrawBuffer);
+ destMask = draw_buffer_enum_to_bitmask(buffer);
+ if (destMask == BAD_MASK) {
+ /* totally bogus buffer */
+ _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffer(buffer)");
+ return;
}
-
- ASSERT(ctx->Driver.Clear);
- newMask = (*ctx->Driver.Clear)( ctx, ddMask, !ctx->Scissor.Enabled,
- x, y, width, height );
-
-#ifdef DEBUG
- {
- GLbitfield legalBits = DD_FRONT_LEFT_BIT |
- DD_FRONT_RIGHT_BIT |
- DD_BACK_LEFT_BIT |
- DD_BACK_RIGHT_BIT |
- DD_DEPTH_BIT |
- DD_STENCIL_BIT |
- DD_ACCUM_BIT;
- assert((newMask & (~legalBits)) == 0);
+ destMask &= supportedMask;
+ if (destMask == 0x0) {
+ /* none of the named color buffers exist! */
+ _mesa_error(ctx, GL_INVALID_OPERATION, "glDrawBuffer(buffer)");
+ return;
}
-#endif
-
- if (newMask)
- _swrast_Clear( ctx, newMask, !ctx->Scissor.Enabled,
- x, y, width, height );
}
+
+ /* if we get here, there's no error so set new state */
+ _mesa_drawbuffers(ctx, 1, &buffer, &destMask);
+
+ /*
+ * Call device driver function.
+ */
+ if (ctx->Driver.DrawBuffers)
+ ctx->Driver.DrawBuffers(ctx, 1, &buffer);
+ else if (ctx->Driver.DrawBuffer)
+ ctx->Driver.DrawBuffer(ctx, buffer);
}
-void
-_mesa_DrawBuffer( GLenum mode )
+/**
+ * Called by glDrawBuffersARB; specifies the destination color renderbuffers
+ * for N fragment program color outputs.
+ * \sa _mesa_DrawBuffer
+ * \param n number of outputs
+ * \param buffers array [n] of renderbuffer names. Unlike glDrawBuffer, the
+ * names cannot specify more than one buffer. For example,
+ * GL_FRONT_AND_BACK is illegal.
+ */
+void GLAPIENTRY
+_mesa_DrawBuffersARB(GLsizei n, const GLenum *buffers)
{
+ GLint output;
+ GLbitfield usedBufferMask, supportedMask;
+ GLbitfield destMask[MAX_DRAW_BUFFERS];
GET_CURRENT_CONTEXT(ctx);
- ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glDrawBuffer");
+ ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
- if (MESA_VERBOSE & VERBOSE_API)
- fprintf(stderr, "glDrawBuffer %s\n", gl_lookup_enum_by_nr(mode));
+ if (!ctx->Extensions.ARB_draw_buffers) {
+ _mesa_error(ctx, GL_INVALID_OPERATION, "glDrawBuffersARB");
+ return;
+ }
+ if (n < 1 || n > (GLsizei) ctx->Const.MaxDrawBuffers) {
+ _mesa_error(ctx, GL_INVALID_VALUE, "glDrawBuffersARB(n)");
+ return;
+ }
- switch (mode) {
- case GL_AUX0:
- case GL_AUX1:
- case GL_AUX2:
- case GL_AUX3:
- /* AUX buffers not implemented in Mesa at this time */
- gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
- return;
- case GL_RIGHT:
- if (!ctx->Visual.StereoFlag) {
- gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
- return;}
- if (ctx->Visual.DBflag)
- ctx->Color.DrawDestMask = FRONT_RIGHT_BIT | BACK_RIGHT_BIT;
- else
- ctx->Color.DrawDestMask = FRONT_RIGHT_BIT;
- break;
- case GL_FRONT_RIGHT:
- if (!ctx->Visual.StereoFlag) {
- gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
- return;
- }
- ctx->Color.DrawDestMask = FRONT_RIGHT_BIT;
- break;
- case GL_BACK_RIGHT:
- if (!ctx->Visual.StereoFlag) {
- gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
- return;
- }
- if (!ctx->Visual.DBflag) {
- gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
+ supportedMask = supported_buffer_bitmask(ctx, ctx->DrawBuffer);
+ usedBufferMask = 0x0;
+
+ /* complicated error checking... */
+ for (output = 0; output < n; output++) {
+ if (buffers[output] == GL_NONE) {
+ destMask[output] = 0x0;
+ }
+ else {
+ destMask[output] = draw_buffer_enum_to_bitmask(buffers[output]);
+ if (destMask[output] == BAD_MASK
+ || _mesa_bitcount(destMask[output]) > 1) {
+ _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffersARB(buffer)");
return;
- }
- ctx->Color.DrawDestMask = BACK_RIGHT_BIT;
- break;
- case GL_BACK_LEFT:
- if (!ctx->Visual.DBflag) {
- gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
+ }
+ destMask[output] &= supportedMask;
+ if (destMask[output] == 0) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glDrawBuffersARB(unsupported buffer)");
return;
}
- ctx->Color.DrawDestMask = BACK_LEFT_BIT;
- break;
- case GL_FRONT_AND_BACK:
- if (!ctx->Visual.DBflag) {
- gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
+ if (destMask[output] & usedBufferMask) {
+ /* can't specify a dest buffer more than once! */
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glDrawBuffersARB(duplicated buffer)");
return;
}
- if (ctx->Visual.StereoFlag)
- ctx->Color.DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT
- | FRONT_RIGHT_BIT | BACK_RIGHT_BIT;
- else
- ctx->Color.DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT;
- break;
- case GL_BACK:
- if (!ctx->Visual.DBflag) {
- gl_error( ctx, GL_INVALID_OPERATION, "glDrawBuffer" );
- return;
- }
- if (ctx->Visual.StereoFlag)
- ctx->Color.DrawDestMask = BACK_LEFT_BIT | BACK_RIGHT_BIT;
- else
- ctx->Color.DrawDestMask = BACK_LEFT_BIT;
- break;
- case GL_LEFT:
- /* never an error */
- if (ctx->Visual.DBflag)
- ctx->Color.DrawDestMask = FRONT_LEFT_BIT | BACK_LEFT_BIT;
- else
- ctx->Color.DrawDestMask = FRONT_LEFT_BIT;
- break;
- case GL_FRONT_LEFT:
- /* never an error */
- ctx->Color.DrawDestMask = FRONT_LEFT_BIT;
- break;
- case GL_FRONT:
- /* never an error */
- if (ctx->Visual.StereoFlag)
- ctx->Color.DrawDestMask = FRONT_LEFT_BIT | FRONT_RIGHT_BIT;
- else
- ctx->Color.DrawDestMask = FRONT_LEFT_BIT;
- break;
- case GL_NONE:
- /* never an error */
- ctx->Color.DrawDestMask = 0;
- break;
- default:
- gl_error( ctx, GL_INVALID_ENUM, "glDrawBuffer" );
- return;
+
+ /* update bitmask */
+ usedBufferMask |= destMask[output];
+ }
}
- /*
- * Make the dest buffer mode more precise if possible
- */
- if (mode == GL_LEFT && !ctx->Visual.DBflag)
- ctx->Color.DriverDrawBuffer = GL_FRONT_LEFT;
- else if (mode == GL_RIGHT && !ctx->Visual.DBflag)
- ctx->Color.DriverDrawBuffer = GL_FRONT_RIGHT;
- else if (mode == GL_FRONT && !ctx->Visual.StereoFlag)
- ctx->Color.DriverDrawBuffer = GL_FRONT_LEFT;
- else if (mode == GL_BACK && !ctx->Visual.StereoFlag)
- ctx->Color.DriverDrawBuffer = GL_BACK_LEFT;
- else
- ctx->Color.DriverDrawBuffer = mode;
+ /* OK, if we get here, there were no errors so set the new state */
+ _mesa_drawbuffers(ctx, n, buffers, destMask);
/*
- * Set current alpha buffer pointer
+ * Call device driver function.
*/
- if (ctx->DrawBuffer->UseSoftwareAlphaBuffers) {
- if (ctx->Color.DriverDrawBuffer == GL_FRONT_LEFT)
- ctx->DrawBuffer->Alpha = ctx->DrawBuffer->FrontLeftAlpha;
- else if (ctx->Color.DriverDrawBuffer == GL_BACK_LEFT)
- ctx->DrawBuffer->Alpha = ctx->DrawBuffer->BackLeftAlpha;
- else if (ctx->Color.DriverDrawBuffer == GL_FRONT_RIGHT)
- ctx->DrawBuffer->Alpha = ctx->DrawBuffer->FrontRightAlpha;
- else if (ctx->Color.DriverDrawBuffer == GL_BACK_RIGHT)
- ctx->DrawBuffer->Alpha = ctx->DrawBuffer->BackRightAlpha;
+ if (ctx->Driver.DrawBuffers)
+ ctx->Driver.DrawBuffers(ctx, n, buffers);
+ else if (ctx->Driver.DrawBuffer)
+ ctx->Driver.DrawBuffer(ctx, buffers[0]);
+}
+
+
+/**
+ * Helper function to set the GL_DRAW_BUFFER state in the context and
+ * current FBO.
+ *
+ * All error checking will have been done prior to calling this function
+ * so nothing should go wrong at this point.
+ *
+ * \param ctx current context
+ * \param n number of color outputs to set
+ * \param buffers array[n] of colorbuffer names, like GL_LEFT.
+ * \param destMask array[n] of BUFFER_BIT_* bitmasks which correspond to the
+ * colorbuffer names. (i.e. GL_FRONT_AND_BACK =>
+ * BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT).
+ */
+void
+_mesa_drawbuffers(GLcontext *ctx, GLuint n, const GLenum *buffers,
+ const GLbitfield *destMask)
+{
+ struct gl_framebuffer *fb = ctx->DrawBuffer;
+ GLbitfield mask[MAX_DRAW_BUFFERS];
+
+ if (!destMask) {
+ /* compute destMask values now */
+ const GLbitfield supportedMask = supported_buffer_bitmask(ctx, fb);
+ GLuint output;
+ for (output = 0; output < n; output++) {
+ mask[output] = draw_buffer_enum_to_bitmask(buffers[output]);
+ ASSERT(mask[output] != BAD_MASK);
+ mask[output] &= supportedMask;
+ }
+ destMask = mask;
}
- /*
- * If we get here there can't have been an error.
- * Now see if device driver can implement the drawing to the target
- * buffer(s). The driver may not be able to do GL_FRONT_AND_BACK mode
- * for example. We'll take care of that in the core code by looping
- * over the individual buffers.
- */
- ASSERT(ctx->Driver.SetDrawBuffer);
- if ( (*ctx->Driver.SetDrawBuffer)(ctx, ctx->Color.DriverDrawBuffer) ) {
- /* All OK, the driver will do all buffer writes */
- ctx->Color.MultiDrawBuffer = GL_FALSE;
+ if (n == 1) {
+ GLuint buf, count = 0;
+ /* init to -1 to help catch errors */
+ fb->_ColorDrawBufferIndexes[0] = -1;
+ for (buf = 0; buf < BUFFER_COUNT; buf++) {
+ if (destMask[0] & (1 << buf)) {
+ fb->_ColorDrawBufferIndexes[count] = buf;
+ count++;
+ }
+ }
+ fb->ColorDrawBuffer[0] = buffers[0];
+ fb->_NumColorDrawBuffers = count;
}
else {
- /* We'll have to loop over the multiple draw buffer targets */
- ctx->Color.MultiDrawBuffer = GL_TRUE;
- /* Set drawing buffer to front for now */
- (void) (*ctx->Driver.SetDrawBuffer)(ctx, GL_FRONT_LEFT);
+ GLuint buf, count = 0;
+ for (buf = 0; buf < n; buf++ ) {
+ if (destMask[buf]) {
+ fb->_ColorDrawBufferIndexes[buf] = _mesa_ffs(destMask[buf]) - 1;
+ fb->ColorDrawBuffer[buf] = buffers[buf];
+ count = buf + 1;
+ }
+ else {
+ fb->_ColorDrawBufferIndexes[buf] = -1;
+ }
+ }
+ /* set remaining outputs to -1 (GL_NONE) */
+ while (buf < ctx->Const.MaxDrawBuffers) {
+ fb->_ColorDrawBufferIndexes[buf] = -1;
+ fb->ColorDrawBuffer[buf] = GL_NONE;
+ buf++;
+ }
+ fb->_NumColorDrawBuffers = count;
+ }
+
+ if (fb->Name == 0) {
+ /* also set context drawbuffer state */
+ GLuint buf;
+ for (buf = 0; buf < ctx->Const.MaxDrawBuffers; buf++) {
+ ctx->Color.DrawBuffer[buf] = fb->ColorDrawBuffer[buf];
+ }
}
- ctx->Color.DrawBuffer = mode;
ctx->NewState |= _NEW_COLOR;
}
-
+/**
+ * Like \sa _mesa_drawbuffers(), this is a helper function for setting
+ * GL_READ_BUFFER state in the context and current FBO.
+ * \param ctx the rendering context
+ * \param buffer GL_FRONT, GL_BACK, GL_COLOR_ATTACHMENT0, etc.
+ * \param bufferIndex the numerical index corresponding to 'buffer'
+ */
void
-_mesa_ReadBuffer( GLenum mode )
+_mesa_readbuffer(GLcontext *ctx, GLenum buffer, GLint bufferIndex)
{
- GET_CURRENT_CONTEXT(ctx);
- ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glReadBuffer");
+ struct gl_framebuffer *fb = ctx->ReadBuffer;
- if (MESA_VERBOSE & VERBOSE_API)
- fprintf(stderr, "glReadBuffer %s\n", gl_lookup_enum_by_nr(mode));
-
- switch (mode) {
- case GL_AUX0:
- case GL_AUX1:
- case GL_AUX2:
- case GL_AUX3:
- /* AUX buffers not implemented in Mesa at this time */
- gl_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
- return;
- case GL_LEFT:
- case GL_FRONT:
- case GL_FRONT_LEFT:
- /* Front-Left buffer, always exists */
- ctx->Pixel.DriverReadBuffer = GL_FRONT_LEFT;
- break;
- case GL_BACK:
- case GL_BACK_LEFT:
- /* Back-Left buffer, requires double buffering */
- if (!ctx->Visual.DBflag) {
- gl_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
- return;
- }
- ctx->Pixel.DriverReadBuffer = GL_BACK_LEFT;
- break;
- case GL_FRONT_RIGHT:
- case GL_RIGHT:
- if (!ctx->Visual.StereoFlag) {
- gl_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
- return;
- }
- ctx->Pixel.DriverReadBuffer = GL_FRONT_RIGHT;
- break;
- case GL_BACK_RIGHT:
- if (!ctx->Visual.StereoFlag || !ctx->Visual.DBflag) {
- gl_error( ctx, GL_INVALID_OPERATION, "glReadBuffer" );
- return;
- }
- ctx->Pixel.DriverReadBuffer = GL_BACK_RIGHT;
- break;
- default:
- gl_error( ctx, GL_INVALID_ENUM, "glReadBuffer" );
- return;
+ if (fb->Name == 0) {
+ /* Only update the per-context READ_BUFFER state if we're bound to
+ * a window-system framebuffer.
+ */
+ ctx->Pixel.ReadBuffer = buffer;
}
- ctx->Pixel.ReadBuffer = mode;
+ fb->ColorReadBuffer = buffer;
+ fb->_ColorReadBufferIndex = bufferIndex;
+
ctx->NewState |= _NEW_PIXEL;
}
-/*
- * GL_MESA_resize_buffers extension
+
+/**
+ * Called by glReadBuffer to set the source renderbuffer for reading pixels.
+ * \param mode color buffer such as GL_FRONT, GL_BACK, etc.
*/
-void
-_mesa_ResizeBuffersMESA( void )
+void GLAPIENTRY
+_mesa_ReadBuffer(GLenum buffer)
{
- GLcontext *ctx = _mesa_get_current_context();
-
- GLuint buf_width, buf_height;
+ struct gl_framebuffer *fb;
+ GLbitfield supportedMask;
+ GLint srcBuffer;
+ GET_CURRENT_CONTEXT(ctx);
+ ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
if (MESA_VERBOSE & VERBOSE_API)
- fprintf(stderr, "glResizeBuffersMESA\n");
+ _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
- /* ask device driver for size of output buffer */
- (*ctx->Driver.GetBufferSize)( ctx, &buf_width, &buf_height );
+ fb = ctx->ReadBuffer;
- /* see if size of device driver's color buffer (window) has changed */
- if (ctx->DrawBuffer->Width == (GLint) buf_width &&
- ctx->DrawBuffer->Height == (GLint) buf_height)
- return;
+ if (MESA_VERBOSE & VERBOSE_API)
+ _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
- ctx->NewState |= _NEW_BUFFERS; /* to update scissor / window bounds */
+ if (fb->Name > 0 && buffer == GL_NONE) {
+ /* This is legal for user-created framebuffer objects */
+ srcBuffer = -1;
+ }
+ else {
+ /* general case / window-system framebuffer */
+ srcBuffer = read_buffer_enum_to_index(buffer);
+ if (srcBuffer == -1) {
+ _mesa_error(ctx, GL_INVALID_ENUM,
+ "glReadBuffer(buffer=0x%x)", buffer);
+ return;
+ }
+ supportedMask = supported_buffer_bitmask(ctx, fb);
+ if (((1 << srcBuffer) & supportedMask) == 0) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glReadBuffer(buffer=0x%x)", buffer);
+ return;
+ }
+ }
+
+ /* OK, all error checking has been completed now */
- /* save buffer size */
- ctx->DrawBuffer->Width = buf_width;
- ctx->DrawBuffer->Height = buf_height;
+ _mesa_readbuffer(ctx, buffer, srcBuffer);
- _swrast_alloc_buffers( ctx );
+ /*
+ * Call device driver function.
+ */
+ if (ctx->Driver.ReadBuffer)
+ (*ctx->Driver.ReadBuffer)(ctx, buffer);
}