/** * \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; GLint i; if (framebufferID > 0) { /* A user-created renderbuffer */ ASSERT(ctx->Extensions.EXT_framebuffer_object); for (i = 0; i < ctx->Const.MaxColorAttachments; i++) { mask |= (BUFFER_BIT_COLOR0 << i); } } else { /* A window system renderbuffer */ 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. * 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, GLsizei n, const GLenum *buffers, const GLbitfield *destMask) { GLbitfield mask[MAX_DRAW_BUFFERS]; GLint 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 _mesa_resizebuffers( GLcontext *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 */ } void GLAPIENTRY _mesa_ResizeBuffersMESA( void ) { GET_CURRENT_CONTEXT(ctx); _mesa_resizebuffers( ctx ); } /* * 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; } /*@}*/