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-rw-r--r--mesalib/src/mesa/main/buffers.c502
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diff --git a/mesalib/src/mesa/main/buffers.c b/mesalib/src/mesa/main/buffers.c
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+/*
+ * Mesa 3-D graphics library
+ * Version: 7.1
+ *
+ * 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"),
+ * 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.
+ */
+
+
+/**
+ * \file buffers.c
+ * glReadBuffer, DrawBuffer functions.
+ */
+
+
+
+#include "glheader.h"
+#include "buffers.h"
+#include "colormac.h"
+#include "context.h"
+#include "enums.h"
+#include "fbobject.h"
+#include "state.h"
+
+
+#define BAD_MASK ~0u
+
+
+/**
+ * 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)
+{
+ 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;
+ }
+
+ for (i = 0; i < fb->Visual.numAuxBuffers; i++) {
+ mask |= (BUFFER_BIT_AUX0 << i);
+ }
+ }
+
+ return mask;
+}
+
+
+/**
+ * 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)
+{
+ 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:
+ case GL_AUX2:
+ case GL_AUX3:
+ return 1 << BUFFER_COUNT; /* invalid, but not BAD_MASK */
+ 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:
+ case GL_AUX2:
+ case GL_AUX3:
+ return BUFFER_COUNT; /* invalid, but not -1 */
+ 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;
+ }
+}
+
+
+/**
+ * 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); /* too complex... */
+
+ if (MESA_VERBOSE & VERBOSE_API) {
+ _mesa_debug(ctx, "glDrawBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
+ }
+
+ 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=0x%x)", buffer);
+ return;
+ }
+ destMask &= supportedMask;
+ if (destMask == 0x0) {
+ /* none of the named color buffers exist! */
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glDrawBuffer(buffer=0x%x)", buffer);
+ return;
+ }
+ }
+
+ /* 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);
+}
+
+
+/**
+ * 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);
+
+ /* Turns out n==0 is a valid input that should not produce an error.
+ * The remaining code below correctly handles the n==0 case.
+ */
+ if (n < 0 || n > (GLsizei) ctx->Const.MaxDrawBuffers) {
+ _mesa_error(ctx, GL_INVALID_VALUE, "glDrawBuffersARB(n)");
+ return;
+ }
+
+ 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;
+ }
+ destMask[output] &= supportedMask;
+ if (destMask[output] == 0) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glDrawBuffersARB(unsupported buffer)");
+ return;
+ }
+ if (destMask[output] & usedBufferMask) {
+ /* can't specify a dest buffer more than once! */
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glDrawBuffersARB(duplicated buffer)");
+ return;
+ }
+
+ /* update bitmask */
+ usedBufferMask |= destMask[output];
+ }
+ }
+
+ /* OK, if we get here, there were no errors so set the new state */
+ _mesa_drawbuffers(ctx, n, buffers, destMask);
+
+ /*
+ * Call device driver function. Note that n can be equal to 0,
+ * in which case we don't want to reference buffers[0], which
+ * may not be valid.
+ */
+ if (ctx->Driver.DrawBuffers)
+ ctx->Driver.DrawBuffers(ctx, n, buffers);
+ else if (ctx->Driver.DrawBuffer)
+ ctx->Driver.DrawBuffer(ctx, n>0? buffers[0]:GL_NONE);
+}
+
+
+/**
+ * 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 (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 {
+ 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->NewState |= _NEW_BUFFERS;
+}
+
+
+/**
+ * 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(GLcontext *ctx, GLenum buffer, GLint bufferIndex)
+{
+ struct gl_framebuffer *fb = ctx->ReadBuffer;
+
+ 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;
+ }
+
+ fb->ColorReadBuffer = buffer;
+ fb->_ColorReadBufferIndex = bufferIndex;
+
+ ctx->NewState |= _NEW_BUFFERS;
+}
+
+
+
+/**
+ * Called by glReadBuffer to set the source renderbuffer for reading pixels.
+ * \param mode color buffer such as GL_FRONT, GL_BACK, etc.
+ */
+void GLAPIENTRY
+_mesa_ReadBuffer(GLenum buffer)
+{
+ struct gl_framebuffer *fb;
+ GLbitfield supportedMask;
+ GLint srcBuffer;
+ GET_CURRENT_CONTEXT(ctx);
+ ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+
+ if (MESA_VERBOSE & VERBOSE_API)
+ _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
+
+ fb = ctx->ReadBuffer;
+
+ if (MESA_VERBOSE & VERBOSE_API)
+ _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
+
+ 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 */
+
+ _mesa_readbuffer(ctx, buffer, srcBuffer);
+ ctx->NewState |= _NEW_BUFFERS;
+
+ /*
+ * Call device driver function.
+ */
+ if (ctx->Driver.ReadBuffer)
+ (*ctx->Driver.ReadBuffer)(ctx, buffer);
+}
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