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-rw-r--r--src/mesa/main/buffers.c752
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diff --git a/src/mesa/main/buffers.c b/src/mesa/main/buffers.c
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+/**
+ * \file buffers.c
+ * Frame buffer management.
+ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version: 6.5
+ *
+ * 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.
+ */
+
+
+#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
+
+
+#if _HAVE_FULL_GL
+void GLAPIENTRY
+_mesa_ClearIndex( GLfloat c )
+{
+ GET_CURRENT_CONTEXT(ctx);
+ ASSERT_OUTSIDE_BEGIN_END(ctx);
+
+ if (ctx->Color.ClearIndex == (GLuint) c)
+ return;
+
+ FLUSH_VERTICES(ctx, _NEW_COLOR);
+ ctx->Color.ClearIndex = (GLuint) c;
+
+ if (!ctx->Visual.rgbMode && ctx->Driver.ClearIndex) {
+ /* it's OK to call glClearIndex in RGBA mode but it should be a NOP */
+ (*ctx->Driver.ClearIndex)( ctx, ctx->Color.ClearIndex );
+ }
+}
+#endif
+
+
+/**
+ * Specify the clear values for the color buffers.
+ *
+ * \param red red color component.
+ * \param green green color component.
+ * \param blue blue color component.
+ * \param alpha alpha component.
+ *
+ * \sa glClearColor().
+ *
+ * Clamps the parameters and updates gl_colorbuffer_attrib::ClearColor. On a
+ * change, flushes the vertices and notifies the driver via the
+ * dd_function_table::ClearColor callback.
+ */
+void GLAPIENTRY
+_mesa_ClearColor( GLclampf red, GLclampf green, GLclampf blue, GLclampf alpha )
+{
+ GLfloat tmp[4];
+ GET_CURRENT_CONTEXT(ctx);
+ ASSERT_OUTSIDE_BEGIN_END(ctx);
+
+ tmp[0] = CLAMP(red, 0.0F, 1.0F);
+ tmp[1] = CLAMP(green, 0.0F, 1.0F);
+ tmp[2] = CLAMP(blue, 0.0F, 1.0F);
+ tmp[3] = CLAMP(alpha, 0.0F, 1.0F);
+
+ if (TEST_EQ_4V(tmp, ctx->Color.ClearColor))
+ return; /* no change */
+
+ FLUSH_VERTICES(ctx, _NEW_COLOR);
+ COPY_4V(ctx->Color.ClearColor, tmp);
+
+ if (ctx->Visual.rgbMode && ctx->Driver.ClearColor) {
+ /* it's OK to call glClearColor in CI mode but it should be a NOP */
+ (*ctx->Driver.ClearColor)(ctx, ctx->Color.ClearColor);
+ }
+}
+
+
+/**
+ * Clear buffers.
+ *
+ * \param mask bit-mask indicating the buffers to be cleared.
+ *
+ * Flushes the vertices and verifies the parameter. If __GLcontextRec::NewState
+ * is set then calls _mesa_update_state() to update gl_frame_buffer::_Xmin,
+ * etc. If the rasterization mode is set to GL_RENDER then requests the driver
+ * to clear the buffers, via the dd_function_table::Clear callback.
+ */
+void GLAPIENTRY
+_mesa_Clear( GLbitfield mask )
+{
+ GET_CURRENT_CONTEXT(ctx);
+ ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+
+ if (MESA_VERBOSE & VERBOSE_API)
+ _mesa_debug(ctx, "glClear 0x%x\n", mask);
+
+ if (mask & ~(GL_COLOR_BUFFER_BIT |
+ GL_DEPTH_BUFFER_BIT |
+ GL_STENCIL_BUFFER_BIT |
+ GL_ACCUM_BUFFER_BIT)) {
+ /* invalid bit set */
+ _mesa_error( ctx, GL_INVALID_VALUE, "glClear(0x%x)", mask);
+ return;
+ }
+
+ if (ctx->NewState) {
+ _mesa_update_state( ctx ); /* update _Xmin, etc */
+ }
+
+ if (ctx->DrawBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
+ _mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
+ "glClear(incomplete framebuffer)");
+ return;
+ }
+
+ 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 bufferMask;
+
+ /* don't clear depth buffer if depth writing disabled */
+ if (!ctx->Depth.Mask)
+ mask &= ~GL_DEPTH_BUFFER_BIT;
+
+ /* Build the bitmask to send to device driver's Clear function.
+ * Note that the GL_COLOR_BUFFER_BIT flag will expand to 0, 1, 2 or 4
+ * of the BUFFER_BIT_FRONT/BACK_LEFT/RIGHT flags, or one of the
+ * BUFFER_BIT_COLORn flags.
+ */
+ bufferMask = 0;
+ if (mask & GL_COLOR_BUFFER_BIT) {
+ bufferMask |= ctx->DrawBuffer->_ColorDrawBufferMask[0];
+ }
+
+ if ((mask & GL_DEPTH_BUFFER_BIT)
+ && ctx->DrawBuffer->Visual.haveDepthBuffer) {
+ bufferMask |= BUFFER_BIT_DEPTH;
+ }
+
+ if ((mask & GL_STENCIL_BUFFER_BIT)
+ && ctx->DrawBuffer->Visual.haveStencilBuffer) {
+ bufferMask |= BUFFER_BIT_STENCIL;
+ }
+
+ if ((mask & GL_ACCUM_BUFFER_BIT)
+ && ctx->DrawBuffer->Visual.haveAccumBuffer) {
+ bufferMask |= BUFFER_BIT_ACCUM;
+ }
+
+ ASSERT(ctx->Driver.Clear);
+ ctx->Driver.Clear( ctx, bufferMask, (GLboolean) !ctx->Scissor.Enabled,
+ x, y, width, height );
+ }
+}
+
+
+
+/**
+ * Return bitmask of BUFFER_BIT_* flags indicating which color buffers are
+ * available to the rendering context.
+ * This depends on the framebuffer we're writing to. 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.
+ */
+static GLbitfield
+supported_buffer_bitmask(const GLcontext *ctx, GLuint framebufferID)
+{
+ GLbitfield mask = 0x0;
+
+ if (framebufferID > 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 renderbuffer */
+ GLint i;
+ mask = BUFFER_BIT_FRONT_LEFT; /* always have this */
+ if (ctx->Visual.stereoMode) {
+ mask |= BUFFER_BIT_FRONT_RIGHT;
+ if (ctx->Visual.doubleBufferMode) {
+ mask |= BUFFER_BIT_BACK_LEFT | BUFFER_BIT_BACK_RIGHT;
+ }
+ }
+ else if (ctx->Visual.doubleBufferMode) {
+ mask |= BUFFER_BIT_BACK_LEFT;
+ }
+
+ for (i = 0; i < ctx->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:
+ 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;
+ 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;
+ 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.
+ */
+void GLAPIENTRY
+_mesa_DrawBuffer(GLenum buffer)
+{
+ GLuint bufferID;
+ 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));
+ }
+
+ bufferID = ctx->DrawBuffer->Name;
+
+ if (buffer == GL_NONE) {
+ destMask = 0x0;
+ }
+ else {
+ const GLbitfield supportedMask = supported_buffer_bitmask(ctx, bufferID);
+ destMask = draw_buffer_enum_to_bitmask(buffer);
+ if (destMask == BAD_MASK) {
+ /* totally bogus buffer */
+ _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffer(buffer)");
+ return;
+ }
+ destMask &= supportedMask;
+ if (destMask == 0x0) {
+ /* none of the named color buffers exist! */
+ _mesa_error(ctx, GL_INVALID_OPERATION, "glDrawBuffer(buffer)");
+ return;
+ }
+ }
+
+ /* if we get here, there's no error so set new state */
+ _mesa_drawbuffers(ctx, 1, &buffer, &destMask);
+}
+
+
+/**
+ * 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;
+ GLuint bufferID;
+ GLbitfield usedBufferMask, supportedMask;
+ GLbitfield destMask[MAX_DRAW_BUFFERS];
+ GET_CURRENT_CONTEXT(ctx);
+ ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+
+ 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;
+ }
+
+ bufferID = ctx->DrawBuffer->Name;
+
+ supportedMask = supported_buffer_bitmask(ctx, bufferID);
+ 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);
+}
+
+
+/**
+ * Set color output state. Traditionally, there was only one color
+ * output, but fragment programs can now have several distinct color
+ * outputs (see GL_ARB_draw_buffers). This function sets the state
+ * for one such color output.
+ * \param ctx current context
+ * \param output which fragment program output
+ * \param buffer buffer to write to (like GL_LEFT)
+ * \param destMask BUFFER_* bitmask
+ * (like BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT).
+ */
+static void
+set_color_output(GLcontext *ctx, GLuint output, GLenum buffer,
+ GLbitfield destMask)
+{
+ struct gl_framebuffer *fb = ctx->DrawBuffer;
+
+ ASSERT(output < ctx->Const.MaxDrawBuffers);
+
+ /* Set per-FBO state */
+ fb->ColorDrawBuffer[output] = buffer;
+ fb->_ColorDrawBufferMask[output] = destMask;
+ /* not really needed, will be set later */
+ fb->_NumColorDrawBuffers[output] = 0;
+
+ /* Set traditional state var */
+ ctx->Color.DrawBuffer[output] = buffer;
+}
+
+
+/**
+ * Helper routine used by _mesa_DrawBuffer, _mesa_DrawBuffersARB and
+ * _mesa_PopAttrib to set drawbuffer state.
+ * 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_* 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)
+{
+ GLbitfield mask[MAX_DRAW_BUFFERS];
+ GLuint output;
+
+ if (!destMask) {
+ /* compute destMask values now */
+ const GLuint bufferID = ctx->DrawBuffer->Name;
+ const GLbitfield supportedMask = supported_buffer_bitmask(ctx, bufferID);
+ 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;
+ }
+
+ for (output = 0; output < n; output++) {
+ set_color_output(ctx, output, buffers[output], destMask[output]);
+ }
+
+ /* set remaining color outputs to NONE */
+ for (output = n; output < ctx->Const.MaxDrawBuffers; output++) {
+ set_color_output(ctx, output, GL_NONE, 0x0);
+ }
+
+ ctx->NewState |= _NEW_COLOR;
+
+ /*
+ * Call device driver function.
+ */
+ if (ctx->Driver.DrawBuffers)
+ ctx->Driver.DrawBuffers(ctx, n, buffers);
+ else if (ctx->Driver.DrawBuffer)
+ ctx->Driver.DrawBuffer(ctx, buffers[0]);
+}
+
+
+
+/**
+ * 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;
+ GLuint bufferID;
+ GET_CURRENT_CONTEXT(ctx);
+ ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+
+ fb = ctx->ReadBuffer;
+ bufferID = fb->Name;
+
+ if (MESA_VERBOSE & VERBOSE_API)
+ _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
+
+ if (bufferID > 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, bufferID);
+ if (((1 << srcBuffer) & supportedMask) == 0) {
+ _mesa_error(ctx, GL_INVALID_OPERATION, "glReadBuffer(buffer=0x%x)", buffer);
+ return;
+ }
+ }
+
+ if (bufferID == 0) {
+ ctx->Pixel.ReadBuffer = buffer;
+ }
+ fb->ColorReadBuffer = buffer;
+ fb->_ColorReadBufferIndex = srcBuffer;
+
+ ctx->NewState |= _NEW_PIXEL;
+
+ /*
+ * Call device driver function.
+ */
+ if (ctx->Driver.ReadBuffer)
+ (*ctx->Driver.ReadBuffer)(ctx, buffer);
+}
+
+
+#if _HAVE_FULL_GL
+
+/**
+ * GL_MESA_resize_buffers extension.
+ *
+ * When this function is called, we'll ask the window system how large
+ * the current window is. If it's a new size, we'll call the driver's
+ * ResizeBuffers function. The driver will then resize its color buffers
+ * as needed, and maybe call the swrast's routine for reallocating
+ * swrast-managed depth/stencil/accum/etc buffers.
+ * \note This function should only be called through the GL API, not
+ * from device drivers (as was done in the past).
+ */
+void GLAPIENTRY
+_mesa_ResizeBuffersMESA( void )
+{
+ GET_CURRENT_CONTEXT(ctx);
+
+ ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH( ctx );
+
+ if (MESA_VERBOSE & VERBOSE_API)
+ _mesa_debug(ctx, "glResizeBuffersMESA\n");
+
+ if (ctx->WinSysDrawBuffer) {
+ GLuint newWidth, newHeight;
+ GLframebuffer *buffer = ctx->WinSysDrawBuffer;
+
+ assert(buffer->Name == 0);
+
+ /* ask device driver for size of output buffer */
+ ctx->Driver.GetBufferSize( buffer, &newWidth, &newHeight );
+
+ /* see if size of device driver's color buffer (window) has changed */
+ if (buffer->Width != newWidth || buffer->Height != newHeight) {
+ if (ctx->Driver.ResizeBuffers)
+ ctx->Driver.ResizeBuffers(ctx, buffer, newWidth, newHeight );
+ }
+ }
+
+ if (ctx->WinSysReadBuffer
+ && ctx->WinSysReadBuffer != ctx->WinSysDrawBuffer) {
+ GLuint newWidth, newHeight;
+ GLframebuffer *buffer = ctx->WinSysReadBuffer;
+
+ assert(buffer->Name == 0);
+
+ /* ask device driver for size of read buffer */
+ ctx->Driver.GetBufferSize( buffer, &newWidth, &newHeight );
+
+ /* see if size of device driver's color buffer (window) has changed */
+ if (buffer->Width != newWidth || buffer->Height != newHeight) {
+ if (ctx->Driver.ResizeBuffers)
+ ctx->Driver.ResizeBuffers(ctx, buffer, newWidth, newHeight );
+ }
+ }
+
+ ctx->NewState |= _NEW_BUFFERS; /* to update scissor / window bounds */
+}
+
+
+/*
+ * XXX move somewhere else someday?
+ */
+void GLAPIENTRY
+_mesa_SampleCoverageARB(GLclampf value, GLboolean invert)
+{
+ GET_CURRENT_CONTEXT(ctx);
+
+ if (!ctx->Extensions.ARB_multisample) {
+ _mesa_error(ctx, GL_INVALID_OPERATION, "glSampleCoverageARB");
+ return;
+ }
+
+ ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH( ctx );
+ ctx->Multisample.SampleCoverageValue = (GLfloat) CLAMP(value, 0.0, 1.0);
+ ctx->Multisample.SampleCoverageInvert = invert;
+ ctx->NewState |= _NEW_MULTISAMPLE;
+}
+
+#endif /* _HAVE_FULL_GL */
+
+
+
+/**
+ * Define the scissor box.
+ *
+ * \param x, y coordinates of the scissor box lower-left corner.
+ * \param width width of the scissor box.
+ * \param height height of the scissor box.
+ *
+ * \sa glScissor().
+ *
+ * Verifies the parameters and updates __GLcontextRec::Scissor. On a
+ * change flushes the vertices and notifies the driver via
+ * the dd_function_table::Scissor callback.
+ */
+void
+_mesa_set_scissor(GLcontext *ctx,
+ GLint x, GLint y, GLsizei width, GLsizei height)
+{
+ if (x == ctx->Scissor.X &&
+ y == ctx->Scissor.Y &&
+ width == ctx->Scissor.Width &&
+ height == ctx->Scissor.Height)
+ return;
+
+ FLUSH_VERTICES(ctx, _NEW_SCISSOR);
+ ctx->Scissor.X = x;
+ ctx->Scissor.Y = y;
+ ctx->Scissor.Width = width;
+ ctx->Scissor.Height = height;
+
+ if (ctx->Driver.Scissor)
+ ctx->Driver.Scissor( ctx, x, y, width, height );
+}
+
+
+void GLAPIENTRY
+_mesa_Scissor( GLint x, GLint y, GLsizei width, GLsizei height )
+{
+ GET_CURRENT_CONTEXT(ctx);
+ ASSERT_OUTSIDE_BEGIN_END(ctx);
+
+ if (width < 0 || height < 0) {
+ _mesa_error( ctx, GL_INVALID_VALUE, "glScissor" );
+ return;
+ }
+
+ if (MESA_VERBOSE & VERBOSE_API)
+ _mesa_debug(ctx, "glScissor %d %d %d %d\n", x, y, width, height);
+
+ _mesa_set_scissor(ctx, x, y, width, height);
+}
+
+
+
+/**********************************************************************/
+/** \name Initialization */
+/*@{*/
+
+/**
+ * Initialize the context's scissor state.
+ * \param ctx the GL context.
+ */
+void
+_mesa_init_scissor(GLcontext *ctx)
+{
+ /* Scissor group */
+ ctx->Scissor.Enabled = GL_FALSE;
+ ctx->Scissor.X = 0;
+ ctx->Scissor.Y = 0;
+ ctx->Scissor.Width = 0;
+ ctx->Scissor.Height = 0;
+}
+
+
+/**
+ * Initialize the context's multisample state.
+ * \param ctx the GL context.
+ */
+void
+_mesa_init_multisample(GLcontext *ctx)
+{
+ ctx->Multisample.Enabled = GL_FALSE;
+ ctx->Multisample.SampleAlphaToCoverage = GL_FALSE;
+ ctx->Multisample.SampleAlphaToOne = GL_FALSE;
+ ctx->Multisample.SampleCoverage = GL_FALSE;
+ ctx->Multisample.SampleCoverageValue = 1.0;
+ ctx->Multisample.SampleCoverageInvert = GL_FALSE;
+}
+
+/*@}*/