diff options
Diffstat (limited to 'src/mesa/drivers/dri/i915/intel_depthstencil.c')
| -rw-r--r-- | src/mesa/drivers/dri/i915/intel_depthstencil.c | 282 |
1 files changed, 282 insertions, 0 deletions
diff --git a/src/mesa/drivers/dri/i915/intel_depthstencil.c b/src/mesa/drivers/dri/i915/intel_depthstencil.c new file mode 100644 index 00000000000..d269a85a3c9 --- /dev/null +++ b/src/mesa/drivers/dri/i915/intel_depthstencil.c @@ -0,0 +1,282 @@ +/************************************************************************** + * + * Copyright 2006 Tungsten Graphics, Inc., Cedar Park, Texas. + * 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, sub license, 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 (including the + * next paragraph) 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 NON-INFRINGEMENT. + * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS 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 "imports.h" +#include "context.h" +#include "depthstencil.h" +#include "fbobject.h" +#include "framebuffer.h" +#include "hash.h" +#include "mtypes.h" +#include "renderbuffer.h" + +#include "intel_context.h" +#include "intel_fbo.h" +#include "intel_depthstencil.h" +#include "intel_regions.h" + + +/** + * The GL_EXT_framebuffer_object allows the user to create their own + * framebuffer objects consisting of color renderbuffers (0 or more), + * depth renderbuffers (0 or 1) and stencil renderbuffers (0 or 1). + * + * The spec considers depth and stencil renderbuffers to be totally independent + * buffers. In reality, most graphics hardware today uses a combined + * depth+stencil buffer (one 32-bit pixel = 24 bits of Z + 8 bits of stencil). + * + * This causes difficulty because the user may create some number of depth + * renderbuffers and some number of stencil renderbuffers and bind them + * together in framebuffers in any combination. + * + * This code manages all that. + * + * 1. Depth renderbuffers are always allocated in hardware as 32bpp + * GL_DEPTH24_STENCIL8 buffers. + * + * 2. Stencil renderbuffers are initially allocated in software as 8bpp + * GL_STENCIL_INDEX8 buffers. + * + * 3. Depth and Stencil renderbuffers use the PairedStencil and PairedDepth + * fields (respectively) to indicate if the buffer's currently paired + * with another stencil or depth buffer (respectively). + * + * 4. When a depth and stencil buffer are initially both attached to the + * current framebuffer, we merge the stencil buffer values into the + * depth buffer (really a depth+stencil buffer). The then hardware uses + * the combined buffer. + * + * 5. Whenever a depth or stencil buffer is reallocated (with + * glRenderbufferStorage) we undo the pairing and copy the stencil values + * from the combined depth/stencil buffer back to the stencil-only buffer. + * + * 6. We also undo the pairing when we find a change in buffer bindings. + * + * 7. If a framebuffer is only using a depth renderbuffer (no stencil), we + * just use the combined depth/stencil buffer and ignore the stencil values. + * + * 8. If a framebuffer is only using a stencil renderbuffer (no depth) we have + * to promote the 8bpp software stencil buffer to a 32bpp hardware + * depth+stencil buffer. + * + */ + + + +static void +map_regions(GLcontext * ctx, + struct intel_renderbuffer *depthRb, + struct intel_renderbuffer *stencilRb) +{ + struct intel_context *intel = intel_context(ctx); + if (depthRb && depthRb->region) { + intel_region_map(intel->intelScreen, depthRb->region); + depthRb->pfMap = depthRb->region->map; + depthRb->pfPitch = depthRb->region->pitch; + } + if (stencilRb && stencilRb->region) { + intel_region_map(intel->intelScreen, stencilRb->region); + stencilRb->pfMap = stencilRb->region->map; + stencilRb->pfPitch = stencilRb->region->pitch; + } +} + +static void +unmap_regions(GLcontext * ctx, + struct intel_renderbuffer *depthRb, + struct intel_renderbuffer *stencilRb) +{ + struct intel_context *intel = intel_context(ctx); + if (depthRb && depthRb->region) { + intel_region_unmap(intel->intelScreen, depthRb->region); + depthRb->pfMap = NULL; + depthRb->pfPitch = 0; + } + if (stencilRb && stencilRb->region) { + intel_region_unmap(intel->intelScreen, stencilRb->region); + stencilRb->pfMap = NULL; + stencilRb->pfPitch = 0; + } +} + + + +/** + * Undo the pairing/interleaving between depth and stencil buffers. + * irb should be a depth/stencil or stencil renderbuffer. + */ +void +intel_unpair_depth_stencil(GLcontext * ctx, struct intel_renderbuffer *irb) +{ + if (irb->PairedStencil) { + /* irb is a depth/stencil buffer */ + struct gl_renderbuffer *stencilRb; + struct intel_renderbuffer *stencilIrb; + + ASSERT(irb->Base._ActualFormat == GL_DEPTH24_STENCIL8_EXT); + + stencilRb = _mesa_lookup_renderbuffer(ctx, irb->PairedStencil); + stencilIrb = intel_renderbuffer(stencilRb); + if (stencilIrb) { + /* need to extract stencil values from the depth buffer */ + ASSERT(stencilIrb->PairedDepth == irb->Base.Name); + map_regions(ctx, irb, stencilIrb); + _mesa_extract_stencil(ctx, &irb->Base, &stencilIrb->Base); + unmap_regions(ctx, irb, stencilIrb); + stencilIrb->PairedDepth = 0; + } + irb->PairedStencil = 0; + } + else if (irb->PairedDepth) { + /* irb is a stencil buffer */ + struct gl_renderbuffer *depthRb; + struct intel_renderbuffer *depthIrb; + + ASSERT(irb->Base._ActualFormat == GL_STENCIL_INDEX8_EXT || + irb->Base._ActualFormat == GL_DEPTH24_STENCIL8_EXT); + + depthRb = _mesa_lookup_renderbuffer(ctx, irb->PairedDepth); + depthIrb = intel_renderbuffer(depthRb); + if (depthIrb) { + /* need to extract stencil values from the depth buffer */ + ASSERT(depthIrb->PairedStencil == irb->Base.Name); + map_regions(ctx, depthIrb, irb); + _mesa_extract_stencil(ctx, &depthIrb->Base, &irb->Base); + unmap_regions(ctx, depthIrb, irb); + depthIrb->PairedStencil = 0; + } + irb->PairedDepth = 0; + } + else { + _mesa_problem(ctx, "Problem in undo_depth_stencil_pairing"); + } + + ASSERT(irb->PairedStencil == 0); + ASSERT(irb->PairedDepth == 0); +} + + +/** + * Examine the depth and stencil renderbuffers which are attached to the + * framebuffer. If both depth and stencil are attached, make sure that the + * renderbuffers are 'paired' (combined). If only depth or only stencil is + * attached, undo any previous pairing. + * + * Must be called if NewState & _NEW_BUFFER (when renderbuffer attachments + * change, for example). + */ +void +intel_validate_paired_depth_stencil(GLcontext * ctx, + struct gl_framebuffer *fb) +{ + struct intel_renderbuffer *depthRb, *stencilRb; + + depthRb = intel_get_renderbuffer(fb, BUFFER_DEPTH); + stencilRb = intel_get_renderbuffer(fb, BUFFER_STENCIL); + + if (depthRb && stencilRb) { + if (depthRb == stencilRb) { + /* Using a user-created combined depth/stencil buffer. + * Nothing to do. + */ + ASSERT(depthRb->Base._BaseFormat == GL_DEPTH_STENCIL_EXT); + ASSERT(depthRb->Base._ActualFormat == GL_DEPTH24_STENCIL8_EXT); + } + else { + /* Separate depth/stencil buffers, need to interleave now */ + ASSERT(depthRb->Base._BaseFormat == GL_DEPTH_COMPONENT); + ASSERT(stencilRb->Base._BaseFormat == GL_STENCIL_INDEX); + /* may need to interleave depth/stencil now */ + if (depthRb->PairedStencil == stencilRb->Base.Name) { + /* OK, the depth and stencil buffers are already interleaved */ + ASSERT(stencilRb->PairedDepth == depthRb->Base.Name); + } + else { + /* need to setup new pairing/interleaving */ + if (depthRb->PairedStencil) { + intel_unpair_depth_stencil(ctx, depthRb); + } + if (stencilRb->PairedDepth) { + intel_unpair_depth_stencil(ctx, stencilRb); + } + + ASSERT(depthRb->Base._ActualFormat == GL_DEPTH24_STENCIL8_EXT); + ASSERT(stencilRb->Base._ActualFormat == GL_STENCIL_INDEX8_EXT || + stencilRb->Base._ActualFormat == GL_DEPTH24_STENCIL8_EXT); + + /* establish new pairing: interleave stencil into depth buffer */ + map_regions(ctx, depthRb, stencilRb); + _mesa_insert_stencil(ctx, &depthRb->Base, &stencilRb->Base); + unmap_regions(ctx, depthRb, stencilRb); + depthRb->PairedStencil = stencilRb->Base.Name; + stencilRb->PairedDepth = depthRb->Base.Name; + } + + } + } + else if (depthRb) { + /* Depth buffer but no stencil buffer. + * We'll use a GL_DEPTH24_STENCIL8 buffer and ignore the stencil bits. + */ + /* can't assert this until storage is allocated: + ASSERT(depthRb->Base._ActualFormat == GL_DEPTH24_STENCIL8_EXT); + */ + /* intel_undo any previous pairing */ + if (depthRb->PairedStencil) { + intel_unpair_depth_stencil(ctx, depthRb); + } + } + else if (stencilRb) { + /* Stencil buffer but no depth buffer. + * Since h/w doesn't typically support just 8bpp stencil w/out Z, + * we'll use a GL_DEPTH24_STENCIL8 buffer and ignore the depth bits. + */ + /* undo any previous pairing */ + if (stencilRb->PairedDepth) { + intel_unpair_depth_stencil(ctx, stencilRb); + } + if (stencilRb->Base._ActualFormat == GL_STENCIL_INDEX8_EXT) { + /* promote buffer to GL_DEPTH24_STENCIL8 for hw rendering */ + _mesa_promote_stencil(ctx, &stencilRb->Base); + ASSERT(stencilRb->Base._ActualFormat == GL_DEPTH24_STENCIL8_EXT); + } + } + + /* Finally, update the fb->_DepthBuffer and fb->_StencilBuffer fields */ + _mesa_update_depth_buffer(ctx, fb, BUFFER_DEPTH); + if (depthRb && depthRb->PairedStencil) + _mesa_update_stencil_buffer(ctx, fb, BUFFER_DEPTH); + else + _mesa_update_stencil_buffer(ctx, fb, BUFFER_STENCIL); + + + /* The hardware should use fb->Attachment[BUFFER_DEPTH].Renderbuffer + * first, if present, then fb->Attachment[BUFFER_STENCIL].Renderbuffer + * if present. + */ +} |