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* i965: Rename intel_emit* to reflect their new location in brw_pipe_controlChris Wilson2015-06-241-1/+1
| | | | | Signed-off-by: Chris Wilson <[email protected]> Reviewed-by: Kenneth Graunke <[email protected]>
* i965/state: Don't use brw->state.dirty.brwJordan Justen2015-03-311-4/+4
| | | | | | | | | | | | | | | Now, we only use ctx->NewDriverState. I used this bash & sed command in the i965 directory: for file in *.[ch] *.[ch]pp; do sed -i -e 's/state\.dirty\.brw/ctx.NewDriverState/g' $file done Followed by manual changes to brw_state_upload.c. Signed-off-by: Jordan Justen <[email protected]> Reviewed-by: Kristian Høgsberg <[email protected]> Reviewed-by: Kenneth Graunke <[email protected]>
* i965: replace Elements() with ARRAY_SIZE()Brian Paul2015-03-021-1/+1
| | | | Acked-by: Ilia Mirkin <[email protected]>
* i965: Do Sandybridge workaround flushes before each primitive.Kenneth Graunke2015-02-171-3/+0
| | | | | | | | | | | | | | | | | | | | | | | Sandybridge requires the post-sync non-zero workaround in a ton of places, and if you ever miss one, the GPU usually hangs. Currently, we try to track exactly when a workaround flush is necessary (via the brw->batch.need_workaround_flush flag). This is tricky to get right, and we've botched it several times in the past. This patch unconditionally performs the post-sync non-zero flush at the start of each primitive's state upload (including BLORP). We drop the needs_workaround_flush flag, and drop all the other callers, as the flush has already been performed. We have no data to indicate that simply flushing all the time will hurt performance, and it has the potential to help stability. v2: Add post-sync workaround to initial GPU state upload to be extra cautious (suggested by Chad Versace). Signed-off-by: Kenneth Graunke <[email protected]> Reviewed-by: Chad Versace <[email protected]>
* i965/gen6: Fix crash with VS+TF after rendering with GSIago Toral Quiroga2015-01-161-1/+1
| | | | | | | | | | | | | | | | | | Rendering with a GS and then using transform feedback with a program that does not have a GS can crash in gen6. The reason for this is that brw_begin_transform_feedback checks brw->geometry_program to decide if there is a GS program, but this is not correct: brw->geometry_program is updated when issuing drawing commands, so after rendering with a GS it will be non-NULL until we draw again with a program that does not have a GS. If the next program uses TF, we will call glBegintransformFeedback before issuing the drawing command and hence brw->geometry_program will be non-NULL if the previous rendering used a GS. The right thing to do here is to check ctx->_Shader->CurrentProgram[MESA_SHADER_GEOMETRY] instead. This is what the gen7 code path does too. Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=87694 Reviewed-by: Tapani Pälli <[email protected]>
* i965: Delete brw_state_flags::cache and related code.Kenneth Graunke2014-12-021-2/+0
| | | | | | | | | It's been merged into brw_state_flags::brw for simplicity and efficiency. Signed-off-by: Kenneth Graunke <[email protected]> Reviewed-by: Kristian Høgsberg <[email protected]> Reviewed-by: Matt Turner <[email protected]>
* i965: Alphabetize brw_tracked_state flags and use a consistent style.Kenneth Graunke2014-11-291-8/+8
| | | | | | | | | | | | | | | | Most of the dirty flags were listed in some arbitrary order. Some used bonus parenthesis. Some put multiple flags on one line, others put one per line. Some used tabs instead of spaces...but only on some lines. This patch settles on one flag per line, in alphabetical order, using spaces instead of tabs, and sheds the unnecessary parentheses. Sorting was mostly done with vim's visual block feature and !sort, although I alphabetized short lists by hand; it was pretty manual. Signed-off-by: Kenneth Graunke <[email protected]> Reviewed-by: Kristian Høgsberg <[email protected]> Reviewed-by: Matt Turner <[email protected]>
* i965/gen6/gs: Fix binding table clash between TF surfaces and textures.Iago Toral Quiroga2014-09-191-26/+54
| | | | | | | | | | | | | | | | | | | | | | | | | | | For gen6 geometry shaders we use the first BRW_MAX_SOL_BINDINGS entries of the binding table for transform feedback surfaces. However, vec4_visitor will setup the binding table so that textures use the same space in the binding table. This is done when calling assign_common_binding_table_offsets(0) as part if its run() method. To fix this clash we add a virtual method to the vec4_visitor hierarchy to assign the binding table offsets, so that we can change this behavior specifically for gen6 geometry shaders by mapping textures right after the first BRW_MAX_SOL_BINDINGS entries. Also, when there is no user-provided geometry shader, we only need to upload the binding table if we have transform feedback, however, in the case of a user-provided geometry shader, we can't only look into transform feedback to make that decision. This fixes multiple piglit tests for textureSize() and texelFetch() when these functions are called from a geometry shader in gen6, like these: bin/textureSize gs sampler2D -fbo -auto bin/texelFetch gs usampler2D -fbo -auto Acked-by: Kenneth Graunke <[email protected]> Reviewed-by: Jordan Justen <[email protected]>
* i965/gen6/gs: Setup SOL surfaces for user-provided geometry shadersSamuel Iglesias Gonsalvez2014-09-191-38/+81
| | | | | | | | | | Update gen6_gs_binding_table and gen6_sol_surface to use user-provided geometry program information when present. This is necessary to implement transform feedback support. Signed-off-by: Samuel Iglesias Gonsalvez <[email protected]> Acked-by: Kenneth Graunke <[email protected]> Reviewed-by: Jordan Justen <[email protected]>
* Revert 5 i965 patches: 8e27a4d2, 373143ed, c5bdf9be, 6f56e142, 88e3d404Jordan Justen2014-09-041-3/+3
| | | | | | | | | | | | | | | | | | | | | | Reverts * "i965: Modify state upload to allow 2 different sets of state atoms." 8e27a4d2b3e4e74e9a77446bce49607433d86be3 * "i965: Modify dirty bit handling to support 2 pipelines." 373143ed9187c4d4ce1e3c486b5dd0880d18ec8b * "i965: Create a macro for checking a dirty bit." c5bdf9be1eca190417998d548fd140c1eca37a54 Conflicts: src/mesa/drivers/dri/i965/brw_context.h * "i965: Create a macro for setting all dirty bits." 6f56e1424d923fd80c84090fbf4506c9eaaffea1 Conflicts: src/mesa/drivers/dri/i965/brw_blorp.cpp src/mesa/drivers/dri/i965/brw_state_cache.c src/mesa/drivers/dri/i965/brw_state_upload.c * "i965: Create a macro for setting a dirty bit." 88e3d404dad009d8cff5124cf8acee7daeaceb64 Signed-off-by: Jordan Justen <[email protected]>
* i965: Create a macro for setting a dirty bit.Paul Berry2014-09-011-3/+3
| | | | | | | This will make it easier to extend dirty bit handling to support compute shaders. Reviewed-by: Jordan Justen <[email protected]>
* mesa/sso: rename Shader to the pointer _ShaderGregory Hainaut2014-03-251-3/+3
| | | | | | | | | | | | | | | | Basically a sed but shaderapi.c and get.c. get.c => GL_CURRENT_PROGAM always refer to the "old" UseProgram behavior shaderapi.c => the old api stil update the Shader object directly V2: formatting improvement V3 (idr): * Rebase fixes after a block of code was moved from ir_to_mesa.cpp to shaderapi.c. * Trivial reformatting. Reviewed-by: Ian Romanick <[email protected]> Reviewed-by: Eric Anholt <[email protected]>
* mesa: Replace ctx->Shader.Current{Vertex,Fragment,Geometry}Program with an ↵Paul Berry2014-01-211-3/+3
| | | | | | | | | | | | | | | | | | | | | array. These are replaced with ctx->Shader.CurrentProgram[MESA_SHADER_{VERTEX,FRAGMENT,GEOMETRY}]. In patches to follow, this will allow us to replace a lot of ad-hoc logic with a variable index into the array. With the exception of the changes to mtypes.h, this patch was generated entirely by the command: find src -type f '(' -iname '*.c' -o -iname '*.cpp' ')' \ -print0 | xargs -0 sed -i \ -e 's/\.CurrentVertexProgram/.CurrentProgram[MESA_SHADER_VERTEX]/g' \ -e 's/\.CurrentGeometryProgram/.CurrentProgram[MESA_SHADER_GEOMETRY]/g' \ -e 's/\.CurrentFragmentProgram/.CurrentProgram[MESA_SHADER_FRAGMENT]/g' Reviewed-by: Chris Forbes <[email protected]> Reviewed-by: Brian Paul <[email protected]>
* i965: Implement glDrawTransformFeedback().Kenneth Graunke2013-10-311-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Implementing the GetTransformFeedbackVertexCount() driver hook allows the VBO module to call us with the right number of vertices. The hardware doesn't directly count the number of vertices written by SOL, so we instead use the SO_NUM_PRIMS_WRITTEN(n) counters and multiply by the number of vertices per primitive. Unfortunately, counting the number of primitives generated is tricky: a program might pause a transform feedback operation, start a second one with a different object, then switch back and resume. Both transform feedback operations share the SO_NUM_PRIMS_WRITTEN counters. To work around this, we save the counter values at Begin, Pause, Resume, and End. This "bookends" each section where transform feedback is active for the current object. Adding up differences of pairs gives us the number of primitives generated. (This is similar to what we do for occlusion queries on platforms without hardware contexts.) v2: Fix missing parenthesis in assertion (caught by Eric Anholt). v3: Reuse prim_count_bo rather than freeing it and immediately allocating a new one (suggested by Topi Pohjolainen). Signed-off-by: Kenneth Graunke <[email protected]> Reviewed-by: Ian Romanick <[email protected]> Reviewed-by: Eric Anholt <[email protected]>
* i965: Implement Pause/ResumeTransformfeedback driver hooks on Gen7+.Kenneth Graunke2013-10-311-0/+5
| | | | | | | | | | | | | | | | | | | | | | The ARB_transform_feedback2 extension introduces the ability to pause and resume transform feedback sessions. Although only one can be active at a time, it's possible to switch between multiple transform feedback objects while paused. In order to facilitate this, we need to save/restore the SO_WRITE_OFFSET registers so that after resuming, the GPU continues writing where it left off. This functionality also exists in ES 3.0, but somehow we completely forgot to implement it. v2: Reduce alignment from 4096 to 64 (it seemed excessive). v3: Use I915_GEM_DOMAIN_INSTRUCTION instead of RENDER, for consistency with other writes. It shouldn't matter on IVB+. Signed-off-by: Kenneth Graunke <[email protected]> Reviewed-by: Ian Romanick <[email protected]> Reviewed-by: Eric Anholt <[email protected]>
* i965: Create a new brw_transform_feedback_object subclass.Kenneth Graunke2013-10-311-0/+29
| | | | | | | | | | | This adds the basic driver hooks to allocate/free the brw variant. It doesn't contain any additional information yet, but it will soon. v2: Use the new _mesa_init_transform_feedback_object helper function (requested by Eric and Ian). Signed-off-by: Kenneth Graunke <[email protected]> Reviewed-by: Eric Anholt <[email protected]>
* i965: Emit post-sync non-zero flush before 3DSTATE_GS_SVB_INDEX.Kenneth Graunke2013-10-281-0/+3
| | | | | | | | | | | | | | | From the comments above intel_emit_post_sync_nonzero_flush: "[DevSNB-C+{W/A}] Before any depth stall flush (including those produced by non-pipelined state commands), software needs to first send a PIPE_CONTROL with no bits set except Post-Sync Operation != 0." This suggests that every non-pipelined (0x79xx) command needs a post-sync non-zero flush before it. Signed-off-by: Kenneth Graunke <[email protected]> Tested-by: Xinkai Chen <[email protected]> Reviewed-by: Eric Anholt <[email protected]> Cc: "9.2" <[email protected]>
* i965/gs: Update defines related to GS surface organization.Paul Berry2013-08-311-3/+3
| | | | | | | | | | | | | | | | Defines that previously referred to VS now refer to VEC4, since they will be shared by the user-programmable vertex shader and geometry shader stages. Defines that previously referred to the Gen6 geometry shader stage (which is only used for transform feedback) are now renamed to explicitly refer to Gen6, to avoid confusion with the Gen7 user-programmable geometry shader stage. Based on work by Eric Anholt <[email protected]>. Reviewed-by: Kenneth Graunke <[email protected]> Reviewed-by: Chad Versace <[email protected]>
* i965: rename legacy gs structs and functions to ff_gs.Paul Berry2013-08-311-6/+6
| | | | | | | | "ff" is for "fixed function". This frees up the name "gs" to refer to user-defined geometry shaders. Reviewed-by: Kenneth Graunke <[email protected]> Reviewed-by: Chad Versace <[email protected]>
* i965: Delete intel_context entirely.Kenneth Graunke2013-07-091-2/+2
| | | | | | | | | | This makes brw_context inherit directly from gl_context; that was the only thing left in intel_context. Signed-off-by: Kenneth Graunke <[email protected]> Acked-by: Chris Forbes <[email protected]> Acked-by: Paul Berry <[email protected]> Acked-by: Anuj Phogat <[email protected]>
* i965: Move intel_context::gen and gt fields to brw_context.Kenneth Graunke2013-07-091-2/+1
| | | | | | | | | | Most functions no longer use intel_context, so this patch additionally removes the local "intel" variables to avoid compiler warnings. Signed-off-by: Kenneth Graunke <[email protected]> Acked-by: Chris Forbes <[email protected]> Acked-by: Paul Berry <[email protected]> Acked-by: Anuj Phogat <[email protected]>
* i965: Pass brw_context to functions rather than intel_context.Kenneth Graunke2013-07-091-2/+1
| | | | | | | | | | | | | | This makes brw_context available in every function that used intel_context. This makes it possible to start migrating fields from intel_context to brw_context. Surprisingly, this actually removes some code, as functions that use OUT_BATCH don't need to declare "intel"; they just use "brw." Signed-off-by: Kenneth Graunke <[email protected]> Acked-by: Chris Forbes <[email protected]> Acked-by: Paul Berry <[email protected]> Acked-by: Anuj Phogat <[email protected]>
* i965: Split BeginTransformFeedback hook into Gen6 and Gen7+ variants.Kenneth Graunke2013-05-211-26/+17
| | | | | | | | | | | Most of the work in BeginTransformFeedback is only necessary on Gen6. We may as well just skip it on Gen7+. v2: Add an intel->gen == 6 assert. Signed-off-by: Kenneth Graunke <[email protected]> Reviewed-by: Eric Anholt <[email protected]> Reviewed-by: Paul Berry <[email protected]>
* i965: Kill software primitive counting entirely.Kenneth Graunke2013-05-211-31/+22
| | | | | | | | | | | | | | | | Now that we have hardware contexts, we don't need to continually reprogram the GS_SVBI_INDEX registers. They're automatically saved and restored with the context, so they can just increment over time. We only need to reset them when starting transform feedback. There's also no reason to delay until the next drawing operation; we can just emit the packet immediately. However, this means we must drop the initialization in brw_invariant_state, as BeginTransformFeedback may occur before the first drawing in a context. Signed-off-by: Kenneth Graunke <[email protected]> Reviewed-by: Eric Anholt <[email protected]> Reviewed-by: Paul Berry <[email protected]>
* i965: Delete unused brw->sol.offset_0_batch_start field.Kenneth Graunke2013-05-211-1/+0
| | | | | | | | This was only used for the the non-hardware context code. Signed-off-by: Kenneth Graunke <[email protected]> Reviewed-by: Eric Anholt <[email protected]> Reviewed-by: Paul Berry <[email protected]>
* i965: Stop using the kernel SOL reset feature.Kenneth Graunke2013-05-211-5/+8
| | | | | | | | We can just do it ourselves with MI_LOAD_REGISTER_IMM. Signed-off-by: Kenneth Graunke <[email protected]> Reviewed-by: Eric Anholt <[email protected]> Reviewed-by: Paul Berry <[email protected]>
* mesa,i965: use NewDriverState to communicate TFB state changes with the driverMarek Olšák2013-04-241-3/+4
| | | | | | | | | | | | | | | | | | | | | | | _NEW_TRANSFORM_FEEDBACK is not used by core Mesa, so it can be removed. Instead, an new private flag is added to i965 to serve the same purpose. If you're new to this: * When creating a context. you can set private dirty flags in gl_context::DriverFlags, eg.: ctx->DriverFlags.NewStateX = BRW_NEW_STATE_X; * When StateX is changed, core Mesa does: ctx->NewDriverState |= ctx->DriverFlags.NewStateX; * When you have to draw, read and clear ctx->NewDriverState. * Pros: not touching NewState, the driver decides the mapping between GL states and hw state groups, unlimited number of flags in core Mesa (still limited number of flags in the driver though) Reviewed-by: Brian Paul <[email protected]> Reviewed-by: Eric Anholt <[email protected]>
* i965/gen6: Reduce updates of transform feedback offsets with HW contexts.Eric Anholt2013-04-101-1/+1
| | | | | | | | | | | | The software-tracked transform feedback offsets (svbi_0_starting_index) are incorrect in the presence of primitive restart, so we were actually updating it with a bogus value if the batch wrapped and we emitted the packet again during a single transform feedback. By reducing state emission, we avoid the bug. Fixes piglit OpenGL 3.1/primitive-restart-xfb flush Reviewed-by: Paul Berry <[email protected]> NOTE: This is a candidate for the 9.1 branch.
* i965/gen7: Skip resetting SOL offsets at batch start with HW contexts.Eric Anholt2013-04-101-0/+9
| | | | | | | | | | | | The software-tracked transform feedback offsets (svbi_0_starting_index) are incorrect in the presence of primitive restart, so we can't reliably compute offsets for our buffer pointers after a batch flush. Thanks to HW contexts, our transform feedback offsets are now saved, so we can just keep using the ones from before the batch wrap. Fixes piglit OpenGL 3.1/primitive-restart-xfb flush Reviewed-by: Paul Berry <[email protected]> NOTE: This is a candidate for the 9.1 branch.
* mesa: Make a function is_transform_feedback_active_and_unpaused.Paul Berry2012-12-181-1/+1
| | | | | | | | | | The rather unweildy logic for determining this condition was repeated in a large number of places. This patch consolidates it to a single inline function. Reviewed-by: Jordan Justen <[email protected]> Reviewed-by: Brian Paul <[email protected]> Reviewed-by: Ian Romanick <[email protected]>
* mesa: refactor _mesa_compute_max_transform_feedback_vertices from i965.Paul Berry2012-12-181-12/+4
| | | | | | | | | | | | | | | | | Previously, the i965 driver contained code to compute the maximum number of vertices that could be written without overflowing any transform feedback buffers. This code wasn't driver-specific, and for GLES3 support we're going to need to use it in core mesa. So this patch moves the code into a core mesa function, _mesa_compute_max_transform_feedback_vertices(). Reviewed-by: Ian Romanick <[email protected]> v2: Eliminate C++-style variable declarations, since these won't work with MSVC. Reviewed-by: Jordan Justen <[email protected]> Reviewed-by: Brian Paul <[email protected]>
* i965/gen6: Fix near-NULL deref in setting up GS binding table for non-XFB.Eric Anholt2012-02-211-5/+8
| | | | | Reviewed-by: Kenneth Graunke <[email protected]> Tested-by: Kenneth Graunke <[email protected]>
* i965: Correct the size of the state batch space allocated for binding tables.Eric Anholt2012-02-211-1/+1
| | | | | | | | | In the gen6 GS case, we were under-counting and so other state would get smashed. In the VS case, we were over-counting, so everything was fine. Reviewed-by: Kenneth Graunke <[email protected]> Tested-by: Kenneth Graunke <[email protected]>
* i965: Fix a bad comment in gen6 sol setup.Eric Anholt2012-02-211-3/+1
| | | | | | | | | This was copy and paste from the VS where I had similar code. We're only looking at things derived from BRW_NEW_VERTEX_PROGRAM in this block. Reviewed-by: Kenneth Graunke <[email protected]> Tested-by: Kenneth Graunke <[email protected]>
* i965: Split the gen6 GS binding table to a separate table.Eric Anholt2012-02-211-2/+56
| | | | | | | | Improves VS state change microbenchmark performance by 7.08729% +/- 1.22289% (n=10) on gen7, because we don't upload the 64 dwords of unused binding table any more. Reviewed-by: Kenneth Graunke <[email protected]>
* i965/gen7: Fix up the transform feedback buffer pointers on later batches.Eric Anholt2012-01-061-0/+1
| | | | | | Fixes piglit EXT_transform_feedback/intervening-read Reviewed-by: Kenneth Graunke <[email protected]>
* i965 gen6: Fix incorrect order of dwords in gen6_update_sol_indices()Paul Berry2011-12-241-1/+1
| | | | | | | | | | | | When updating SOL indices, we were accidentally putting the starting index in dword 1 and the SVBI number to increment in dword 2--these should be reversed. Usually both of these values are zero, so we didn't see any problem. However, if a transform feedback operation spans multiple batch buffers, the starting index will be nonzero. Fixes piglit test "EXT_transform_feedback/intervening-read output". Reviewed-by: Kenneth Graunke <[email protected]>
* i965 gen6: Resend binding table pointer after updating SOL bindings.Paul Berry2011-12-231-0/+2
| | | | | | | | | After creating new binding table entries for transform feedback, we need to set the dirty flag BRW_NEW_SURFACES, so that a new binding table pointer will be sent to the hardware. Otherwise the new binding table entries will not take effect. Reviewed-by: Kenneth Graunke <[email protected]>
* i965 gen6: Implement transform feedback pause/resume functionality.Paul Berry2011-12-231-1/+2
| | | | | | | | | Although i965 gen6 does not yet support ARB_transform_feedback2 or NV_transform_feedback2, it needs to support pause/resume functionality so that meta-ops will work correctly. Reviewed-by: Eric Anholt <[email protected]> Reviewed-by: Kenneth Graunke <[email protected]>
* i965 gen6: Ensure correct transform feedback indices on new batch.Paul Berry2011-12-201-8/+30
| | | | | | | | | | | | | | | | We don't currently have kernel support for saving GPU registers on a context switch, so if multiple processes are performing transform feedback at the same time, their SVBI registers will interfere with each other. To avoid this situation, we keep a software shadow of the state of the SVBI 0 register (which is the only register we use), and re-upload it on every new batch. The function that updates the shadow state of SVBI 0 is called brw_update_primitive_count, since it will also be used to update the counters for the PRIMITIVES_GENERATED and TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN queries. Reviewed-by: Kenneth Graunke <[email protected]>
* i965: Implement bounds checking for transform feedback output.Kenneth Graunke2011-12-201-0/+38
| | | | | Signed-off-by: Kenneth Graunke <[email protected]> Reviewed-by: Paul Berry <[email protected]>
* i965: Flush pipeline on EndTransformFeedback.Paul Berry2011-12-201-0/+16
| | | | | | | | | | | | | | | | | | | | | | | A common use case for transform feedback is to perform one draw operation that writes transform feedback output to a buffer, followed by a second draw operation that consumes that buffer as vertex input. Since vertex input is consumed at an earlier pipeline stage than writing transform feedback output, we need to flush the pipeline to ensure that the transform feedback output is completely written before the data is consumed. In an ideal world, we would do some dependency tracking, so that we would only flush the pipeline if the next draw call was about to consume data generated by a previous draw call in the same batch. However, since we don't have that sort of dependency tracking infrastructure right now, we just unconditionally flush the buffer every time glEndTransformFeedback() is called. This will cause a performance hit compared to the ideal case (since we will sometimes flush the pipeline unnecessarily), but fortunately the performance hit will be confined to circumstances where transform feedback is in use. Reviewed-by: Kenneth Graunke <[email protected]> Reviewed-by: Eric Anholt <[email protected]>
* i965 gen6: Initial implementation of transform feedback.Paul Berry2011-12-201-0/+71
This patch adds basic transform feedback capability for Gen6 hardware. This consists of several related pieces of functionality: (1) In gen6_sol.c, we set up binding table entries for use by transform feedback. We use one binding table entry per transform feedback varying (this allows us to avoid doing pointer arithmetic in the shader, since we can set up the binding table entries with the appropriate offsets and surface pitches to place each varying at the correct address). (2) In brw_context.c, we advertise the hardware capabilities, which are as follows: MAX_TRANSFORM_FEEDBACK_INTERLEAVED_COMPONENTS 64 MAX_TRANSFORM_FEEDBACK_SEPARATE_ATTRIBS 4 MAX_TRANSFORM_FEEDBACK_SEPARATE_COMPONENTS 16 OpenGL 3.0 requires these values to be at least 64, 4, and 4, respectively. The reason we advertise a larger value than required for MAX_TRANSFORM_FEEDBACK_SEPARATE_COMPONENTS is that we have already set aside 64 binding table entries, so we might as well make them all available in both separate attribs and interleaved modes. (3) We set aside a single SVBI ("streamed vertex buffer index") for use by transform feedback. The hardware supports four independent SVBI's, but we only need one, since vertices are added to all transform feedback buffers at the same rate. Note: at the moment this index is reset to 0 only when the driver is initialized. It needs to be reset to 0 whenever BeginTransformFeedback() is called, and otherwise preserved. (4) In brw_gs_emit.c and brw_gs.c, we modify the geometry shader program to output transform feedback data as a side effect. (5) In gen6_gs_state.c, we configure the geometry shader stage to handle the SVBI pointer correctly. Note: ordering of vertices is not yet correct for triangle strips (alternate triangles are improperly oriented). This will be addressed in a future patch. Reviewed-by: Kenneth Graunke <[email protected]> Reviewed-by: Eric Anholt <[email protected]>
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