[Mesa-dev] [PATCH] Implement HW accelerated GL_SELECT
Micael
kam1kaz3 at gmail.com
Wed Aug 24 07:35:40 PDT 2011
Any more feedback regarding this?
I now don't have much time to work on it again, but I may find some, so
knowing what's left to do would be nice...
On Thu, Aug 4, 2011 at 2:59 PM, Micael Dias <kam1kaz3 at gmail.com> wrote:
> ---
> src/mesa/SConscript | 1 +
> src/mesa/main/fbobject.c | 16 +-
> src/mesa/main/fbobject.h | 6 +
> src/mesa/sources.mak | 1 +
> src/mesa/state_tracker/st_cb_feedback.c | 21 +-
> src/mesa/state_tracker/st_context.h | 10 +
> src/mesa/state_tracker/st_draw.h | 17 +
> src/mesa/state_tracker/st_draw_select_emul.c | 490
> ++++++++++++++++++++++++++
> 8 files changed, 549 insertions(+), 13 deletions(-)
> create mode 100644 src/mesa/state_tracker/st_draw_select_emul.c
>
> diff --git a/src/mesa/SConscript b/src/mesa/SConscript
> index 24e2155..288b162 100644
> --- a/src/mesa/SConscript
> +++ b/src/mesa/SConscript
> @@ -262,6 +262,7 @@ statetracker_sources = [
> 'state_tracker/st_debug.c',
> 'state_tracker/st_draw.c',
> 'state_tracker/st_draw_feedback.c',
> + 'state_tracker/st_draw_select_emul.c',
> 'state_tracker/st_extensions.c',
> 'state_tracker/st_format.c',
> 'state_tracker/st_gen_mipmap.c',
> diff --git a/src/mesa/main/fbobject.c b/src/mesa/main/fbobject.c
> index 82eb7fb..1aea62b 100644
> --- a/src/mesa/main/fbobject.c
> +++ b/src/mesa/main/fbobject.c
> @@ -1560,8 +1560,8 @@ _mesa_IsFramebufferEXT(GLuint framebuffer)
> * (render to texture). Call ctx->Driver.RenderTexture() for such
> * attachments.
> */
> -static void
> -check_begin_texture_render(struct gl_context *ctx, struct gl_framebuffer
> *fb)
> +void
> +_mesa_check_begin_texture_render(struct gl_context *ctx, struct
> gl_framebuffer *fb)
> {
> GLuint i;
> ASSERT(ctx->Driver.RenderTexture);
> @@ -1583,8 +1583,8 @@ check_begin_texture_render(struct gl_context *ctx,
> struct gl_framebuffer *fb)
> * If so, call ctx->Driver.FinishRenderTexture() for each texture to
> * notify the device driver that the texture image may have changed.
> */
> -static void
> -check_end_texture_render(struct gl_context *ctx, struct gl_framebuffer
> *fb)
> +void
> +_mesa_check_end_texture_render(struct gl_context *ctx, struct
> gl_framebuffer *fb)
> {
> if (is_winsys_fbo(fb))
> return; /* can't render to texture with winsys framebuffers */
> @@ -1713,7 +1713,7 @@ _mesa_BindFramebufferEXT(GLenum target, GLuint
> framebuffer)
> FLUSH_VERTICES(ctx, _NEW_BUFFERS);
>
> /* check if old readbuffer was render-to-texture */
> - check_end_texture_render(ctx, oldReadFb);
> + _mesa_check_end_texture_render(ctx, oldReadFb);
>
> _mesa_reference_framebuffer(&ctx->ReadBuffer, newReadFb);
> }
> @@ -1723,13 +1723,13 @@ _mesa_BindFramebufferEXT(GLenum target, GLuint
> framebuffer)
>
> /* check if old read/draw buffers were render-to-texture */
> if (!bindReadBuf)
> - check_end_texture_render(ctx, oldReadFb);
> + _mesa_check_end_texture_render(ctx, oldReadFb);
>
> if (oldDrawFb != oldReadFb)
> - check_end_texture_render(ctx, oldDrawFb);
> + _mesa_check_end_texture_render(ctx, oldDrawFb);
>
> /* check if newly bound framebuffer has any texture attachments */
> - check_begin_texture_render(ctx, newDrawFb);
> + _mesa_check_begin_texture_render(ctx, newDrawFb);
>
> _mesa_reference_framebuffer(&ctx->DrawBuffer, newDrawFb);
> }
> diff --git a/src/mesa/main/fbobject.h b/src/mesa/main/fbobject.h
> index 7eb2005..ca6251c 100644
> --- a/src/mesa/main/fbobject.h
> +++ b/src/mesa/main/fbobject.h
> @@ -101,6 +101,12 @@ _mesa_is_legal_color_format(const struct gl_context
> *ctx, GLenum baseFormat);
> extern GLenum
> _mesa_base_fbo_format(struct gl_context *ctx, GLenum internalFormat);
>
> +extern void
> +_mesa_check_begin_texture_render(struct gl_context *ctx, struct
> gl_framebuffer *fb);
> +
> +extern void
> +_mesa_check_end_texture_render(struct gl_context *ctx, struct
> gl_framebuffer *fb);
> +
> extern GLboolean GLAPIENTRY
> _mesa_IsRenderbufferEXT(GLuint renderbuffer);
>
> diff --git a/src/mesa/sources.mak b/src/mesa/sources.mak
> index 4b2ec08..9af4079 100644
> --- a/src/mesa/sources.mak
> +++ b/src/mesa/sources.mak
> @@ -229,6 +229,7 @@ STATETRACKER_SOURCES = \
> state_tracker/st_debug.c \
> state_tracker/st_draw.c \
> state_tracker/st_draw_feedback.c \
> + state_tracker/st_draw_select_emul.c \
> state_tracker/st_extensions.c \
> state_tracker/st_format.c \
> state_tracker/st_gen_mipmap.c \
> diff --git a/src/mesa/state_tracker/st_cb_feedback.c
> b/src/mesa/state_tracker/st_cb_feedback.c
> index 9b85a39..c96c97c 100644
> --- a/src/mesa/state_tracker/st_cb_feedback.c
> +++ b/src/mesa/state_tracker/st_cb_feedback.c
> @@ -276,17 +276,28 @@ st_RenderMode(struct gl_context *ctx, GLenum newMode
> )
> {
> struct st_context *st = st_context(ctx);
> struct draw_context *draw = st->draw;
> + bool hw_acc_path = _mesa_getenv("MESA_HW_SELECT") &&
> !st->select_emul.hw_unsupported;
>
> if (newMode == GL_RENDER) {
> /* restore normal VBO draw function */
> vbo_set_draw_func(ctx, st_draw_vbo);
> }
> else if (newMode == GL_SELECT) {
> - if (!st->selection_stage)
> - st->selection_stage = draw_glselect_stage(ctx, draw);
> - draw_set_rasterize_stage(draw, st->selection_stage);
> - /* Plug in new vbo draw function */
> - vbo_set_draw_func(ctx, st_feedback_draw_vbo);
> + if (hw_acc_path) {
> + if (st_select_emul_begin(ctx)) {
> + vbo_set_draw_func(ctx, st_select_draw_func);
> + }
> + else {
> + hw_acc_path = false;
> + }
> + }
> + if (!hw_acc_path) {
> + if (!st->selection_stage)
> + st->selection_stage = draw_glselect_stage(ctx, draw);
> + draw_set_rasterize_stage(draw, st->selection_stage);
> + /* Plug in new vbo draw function */
> + vbo_set_draw_func(ctx, st_feedback_draw_vbo);
> + }
> }
> else {
> if (!st->feedback_stage)
> diff --git a/src/mesa/state_tracker/st_context.h
> b/src/mesa/state_tracker/st_context.h
> index 0a32202..8a8e11a 100644
> --- a/src/mesa/state_tracker/st_context.h
> +++ b/src/mesa/state_tracker/st_context.h
> @@ -207,6 +207,16 @@ struct st_context
>
> int32_t draw_stamp;
> int32_t read_stamp;
> +
> + /* data related to hw accelerated GL_SELECT */
> + struct gl_selection_emul
> + {
> + GLboolean hw_unsupported;
> + struct gl_framebuffer *fbo;
> + GLuint rb_depth_name;
> + GLuint rb_color_name;
> + void *fs;
> + } select_emul;
> };
>
>
> diff --git a/src/mesa/state_tracker/st_draw.h
> b/src/mesa/state_tracker/st_draw.h
> index a7b50ce..d27e321 100644
> --- a/src/mesa/state_tracker/st_draw.h
> +++ b/src/mesa/state_tracker/st_draw.h
> @@ -87,5 +87,22 @@ pointer_to_offset(const void *ptr)
> return (unsigned) (((unsigned long) ptr) & 0xffffffffUL);
> }
>
> +/* Functions used by the hw accelerated GL_SELECT emulator
> + */
> +extern bool
> +st_select_emul_begin(struct gl_context *ctx);
> +
> +extern void
> +st_select_emul_end(struct gl_context *ctx);
> +
> +extern void
> +st_select_draw_func(struct gl_context *ctx,
> + const struct gl_client_array **arrays,
> + const struct _mesa_prim *prims,
> + GLuint nr_prims,
> + const struct _mesa_index_buffer *ib,
> + GLboolean index_bounds_valid,
> + GLuint min_index,
> + GLuint max_index);
>
> #endif
> diff --git a/src/mesa/state_tracker/st_draw_select_emul.c
> b/src/mesa/state_tracker/st_draw_select_emul.c
> new file mode 100644
> index 0000000..d6bb244
> --- /dev/null
> +++ b/src/mesa/state_tracker/st_draw_select_emul.c
> @@ -0,0 +1,490 @@
>
> +/**************************************************************************
> + *
> + * Copyright 2011 Micael Dias <kam1kaz3 (at) gmail (dot) com>,
> + * Pierre-Eric Pelloux-Prayer
> + * 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.
> + *
> +
> **************************************************************************/
> +
> +/**
> + * This file contains code that attempts to accelerate GL_SELECT
> rendering.
> + * It was created with the intent of solving the following bug:
> + * https://bugs.freedesktop.org/show_bug.cgi?id=34495
> + *
> + * This code is a rewritten version of the patch "GL_SELECT hw support v5"
> + * posted by user Pierre-Eric Pelloux-Prayer in the previously mentioned
> bug.
> + *
> + * In order to test this code, the env. variable MESA_HW_SELECT should be
> + * exported.
> + *
> + * How this algorithm works:
> + * - When in GL_SELECT mode, draw calls are redirected to
> st_select_draw_func()
> + * which configures states in a way that makes the rendered primitives
> draw
> + * to a custom FBO that stores depth values (both min and max values) and
> + * emits these values through _mesa_update_hitflag().
> + */
> +
> +#include "main/imports.h"
> +#include "main/image.h"
> +#include "main/macros.h"
> +#include "main/mfeatures.h"
> +#include "main/hash.h"
> +
> +#include "main/context.h"
> +#include "main/enable.h"
> +#include "main/fbobject.h"
> +#include "main/depth.h"
> +#include "main/state.h"
> +#include "main/scissor.h"
> +#include "main/viewport.h"
> +#include "main/framebuffer.h"
> +#include "main/feedback.h"
> +
> +#include "vbo/vbo.h"
> +
> +#include "st_context.h"
> +#include "st_atom.h"
> +#include "st_cb_bufferobjects.h"
> +#include "st_draw.h"
> +#include "st_program.h"
> +#include "st_texture.h"
> +#include "st_cb_readpixels.h"
> +
> +#include "pipe/p_context.h"
> +#include "pipe/p_defines.h"
> +#include "pipe/p_state.h"
> +#include "pipe/p_format.h"
> +#include "pipe/p_shader_tokens.h"
> +#include "util/u_inlines.h"
> +#include "util/u_simple_shaders.h"
> +#include "cso_cache/cso_context.h"
> +#include "tgsi/tgsi_ureg.h"
> +
> +#include "draw/draw_private.h"
> +#include "draw/draw_context.h"
> +
> +/**
> + * Custom fragment shader that does nothing but ouput a constant color
> + */
> +static void*
> +st_select_emul_create_fs(struct gl_context *ctx)
> +{
> + struct st_context *st = st_context(ctx);
> + struct pipe_context *pipe = st->pipe;
> + struct ureg_program *ureg;
> + struct ureg_dst out;
> + struct ureg_src imm;
> +
> + ureg = ureg_create( TGSI_PROCESSOR_FRAGMENT );
> + if (ureg == NULL)
> + return NULL;
> +
> + out = ureg_DECL_output( ureg,
> + TGSI_SEMANTIC_COLOR,
> + 0 );
> +
> + imm = ureg_imm4f( ureg, 0.0f, 0.0f, 0.0f, 1.0f );
> +
> + ureg_MOV( ureg, out, imm );
> + ureg_END( ureg );
> +
> + return ureg_create_shader_and_destroy( ureg, pipe );
> +}
> +
> +/**
> + * Clears the depth values of our FBO by setting the
> + * 1st pixel to 1.0f and the 2nd to 0.0f
> + */
> +static void
> +st_select_emul_clear_fbo(struct gl_context *ctx)
> +{
> + struct st_context *st = st_context(ctx);
> + struct gl_scissor_attrib saved_scissor;
> + struct gl_framebuffer *saved_fbo = NULL;
> + GLfloat clearDepth;
> +
> + /* save states */
> + saved_scissor = ctx->Scissor;
> + if (ctx->DrawBuffer) {
> + _mesa_reference_framebuffer(&saved_fbo, ctx->DrawBuffer);
> + }
> + clearDepth = ctx->Depth.Clear;
> +
> + /* hack needed because Clear does nothing if render mode != GL_RENDER
> */
> + ctx->RenderMode = GL_RENDER;
> +
> + /* disable old draw fbo */
> + if (saved_fbo) {
> + /* XXX: needs flushing? */
> + _mesa_check_end_texture_render(ctx, saved_fbo);
> + }
> +
> + /* use our fbo */
> + _mesa_check_begin_texture_render(ctx, st->select_emul.fbo);
> + _mesa_reference_framebuffer(&ctx->DrawBuffer, st->select_emul.fbo);
> +
> + /* update fbo */
> + _mesa_update_framebuffer(ctx);
> +
> + /* make sure context is up to date */
> + _mesa_update_state(ctx);
> +
> + /* enable scissor */
> + ctx->Scissor.Enabled = GL_TRUE;
> +
> + /* clear min-Z */
> + ctx->Scissor.X = 0;
> + ctx->Scissor.Y = 0;
> + ctx->Scissor.Width = 1;
> + ctx->Scissor.Height = 1;
> + ctx->Depth.Clear = 1.0f;
> + if (ctx->Driver.ClearDepth)
> + (*ctx->Driver.ClearDepth)(ctx, ctx->Depth.Clear);
> + ctx->NewState |= _NEW_SCISSOR | _NEW_DEPTH | _NEW_BUFFERS;
> + _mesa_update_state(ctx);
> + ctx->Driver.Clear(ctx, BUFFER_BIT_DEPTH);
> +
> + /* clear max-Z */
> + ctx->Scissor.X = 1;
> + ctx->Scissor.Y = 0;
> + ctx->Scissor.Width = 1;
> + ctx->Scissor.Height = 1;
> + ctx->Depth.Clear = 0.0f;
> + if (ctx->Driver.ClearDepth)
> + (*ctx->Driver.ClearDepth)(ctx, ctx->Depth.Clear);
> + ctx->NewState |= _NEW_SCISSOR | _NEW_DEPTH;
> + _mesa_update_state(ctx);
> + ctx->Driver.Clear(ctx, BUFFER_BIT_DEPTH);
> +
> + /* restore states */
> + _mesa_check_end_texture_render(ctx, st->select_emul.fbo);
> + if (saved_fbo) {
> + _mesa_check_begin_texture_render(ctx, saved_fbo);
> + _mesa_reference_framebuffer(&ctx->DrawBuffer, saved_fbo);
> + _mesa_reference_framebuffer(&saved_fbo, NULL);
> + }
> + else
> + _mesa_reference_framebuffer(&ctx->DrawBuffer, NULL);
> +
> + ctx->RenderMode = GL_SELECT;
> + ctx->Depth.Clear = clearDepth;
> + if (ctx->Driver.ClearDepth)
> + (*ctx->Driver.ClearDepth)(ctx, ctx->Depth.Clear);
> + ctx->Scissor = saved_scissor;
> + ctx->NewState |= _NEW_SCISSOR | _NEW_DEPTH | _NEW_BUFFERS;
> + _mesa_update_state(ctx);
> +}
> +
> +/**
> + * Clean up data
> + */
> +static void
> +st_select_emul_destroy_fbo(struct gl_context *ctx)
> +{
> + struct st_context *st = st_context(ctx);
> + if (st->select_emul.rb_color_name) {
> + _mesa_DeleteRenderbuffersEXT(1, &st->select_emul.rb_color_name);
> + st->select_emul.rb_color_name = 0;
> + }
> + if (st->select_emul.rb_depth_name) {
> + _mesa_DeleteRenderbuffersEXT(1, &st->select_emul.rb_depth_name);
> + st->select_emul.rb_depth_name = 0;
> + }
> + if (st->select_emul.fbo) {
> + _mesa_DeleteFramebuffersEXT(1, &st->select_emul.fbo->Name);
> + _mesa_reference_framebuffer(&st->select_emul.fbo, NULL);
> + }
> + if (st->select_emul.fs) {
> + cso_delete_fragment_shader(st->cso_context, st->select_emul.fs);
> + st->select_emul.fs = NULL;
> + }
> +}
> +
> +/**
> + * Create and setup FBO needed for our operations
> + */
> +static bool
> +st_select_emul_create_fbo(struct gl_context *ctx)
> +{
> + GLuint fboName;
> + struct st_context *st = st_context(ctx);
> +
> + /* make sure we don't leak memory */
> + st_select_emul_destroy_fbo(ctx);
> +
> + /* create buffer names */
> + _mesa_GenFramebuffersEXT(1, &fboName);
> + _mesa_GenRenderbuffersEXT(1, &st->select_emul.rb_depth_name);
> + _mesa_GenRenderbuffersEXT(1, &st->select_emul.rb_color_name);
> +
> + /* allocate buffers' memory */
> + _mesa_BindFramebufferEXT(GL_FRAMEBUFFER, fboName);
> + _mesa_BindRenderbufferEXT(GL_RENDERBUFFER,
> st->select_emul.rb_depth_name);
> + _mesa_RenderbufferStorageEXT(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, 2,
> 1);
> + _mesa_BindRenderbufferEXT(GL_RENDERBUFFER,
> st->select_emul.rb_color_name);
> + _mesa_RenderbufferStorageEXT(GL_RENDERBUFFER, GL_RGBA, 2, 1);
> + _mesa_BindRenderbufferEXT(GL_RENDERBUFFER, 0);
> +
> + /* setup fbo */
> + _mesa_FramebufferRenderbufferEXT(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT,
> + GL_RENDERBUFFER,
> + st->select_emul.rb_depth_name);
> + _mesa_FramebufferRenderbufferEXT(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
> + GL_RENDERBUFFER,
> + st->select_emul.rb_color_name);
> +
> + if (_mesa_CheckFramebufferStatusEXT(GL_FRAMEBUFFER) !=
> GL_FRAMEBUFFER_COMPLETE) {
> + st_select_emul_destroy_fbo(ctx);
> + return false;
> + }
> +
> + _mesa_BindFramebufferEXT(GL_FRAMEBUFFER, 0);
> +
> + /* get fbo pointer */
> + st->select_emul.fbo = _mesa_lookup_framebuffer(ctx, fboName);
> +
> + /* create fragment shader */
> + st->select_emul.fs = st_select_emul_create_fs(ctx);
> +
> + /* check fbo pointer validity */
> + if (!st->select_emul.fbo) {
> + st_select_emul_destroy_fbo(ctx);
> + return false;
> + }
> +
> + return true;
> +}
> +
> +/**
> + * Called when entering GL_SELECT mode.
> + * This function initializes our private data and clears
> + * depth so that the next draw call will have it ready.
> + */
> +bool
> +st_select_emul_begin(struct gl_context *ctx)
> +{
> + struct st_context *st = st_context(ctx);
> +
> + /* perform an hw caps check once */
> + static bool hw_checked = false;
> + if (!hw_checked) {
> + hw_checked = true;
> + /* XXX: is this a proper way to check for hw support? */
> + if (!ctx->Driver.ReadPixels ||
> + !ctx->Driver.DrawPixels ||
> + !ctx->Driver.NewFramebuffer ||
> + !ctx->Driver.NewRenderbuffer) {
> + st->select_emul.hw_unsupported = true;
> + return false;
> + }
> + }
> +
> + /* initialize fbo if not yet initialized */
> + if (!st->select_emul.fbo) {
> + if (!st_select_emul_create_fbo(ctx)) {
> + return false;
> + }
> + }
> +
> + /* clear FBO */
> + st_select_emul_clear_fbo(ctx);
> +
> + return true;
> +}
> +
> +void
> +st_select_emul_end(struct gl_context *ctx)
> +{
> + st_select_emul_destroy_fbo(ctx);
> +}
> +
> +/**
> + * Reads into our FBO and emit z-buffer results
> + * called by st_select_draw_func()
> + */
> +static void
> +st_select_emul_update_hits(struct gl_context *ctx)
> +{
> + struct st_context *st = st_context(ctx);
> + struct gl_framebuffer *saved_fbo = NULL;
> + float zData[2];
> +
> + /* set state */
> + if (ctx->ReadBuffer) {
> + _mesa_reference_framebuffer(&saved_fbo, ctx->ReadBuffer);
> + _mesa_check_end_texture_render(ctx, saved_fbo);
> + }
> + _mesa_check_begin_texture_render(ctx, st->select_emul.fbo);
> + _mesa_reference_framebuffer(&ctx->ReadBuffer, st->select_emul.fbo);
> +
> + /* update fbo */
> + _mesa_update_framebuffer( ctx );
> +
> + /* update state */
> + ctx->NewState |= _NEW_BUFFERS;
> + _mesa_update_state( ctx );
> +
> + /* read pixels */
> + ctx->Driver.ReadPixels( ctx, 0, 0, 2, 1,
> + GL_DEPTH_COMPONENT, GL_FLOAT,
> + &ctx->Pack, (void*)zData );
> +
> + /* emit z-buffer results */
> + if (zData[0] != 1.0f)
> + _mesa_update_hitflag( ctx, zData[0] );
> + if (zData[1] != 0.0f)
> + _mesa_update_hitflag( ctx, zData[1] );
> +
> + /* clear FBO */
> + st_select_emul_clear_fbo(ctx);
> +
> + /* restore state */
> + _mesa_check_end_texture_render(ctx, st->select_emul.fbo);
> + if (saved_fbo) {
> + _mesa_check_begin_texture_render(ctx, saved_fbo);
> + _mesa_reference_framebuffer(&ctx->ReadBuffer, saved_fbo);
> + _mesa_reference_framebuffer(&saved_fbo, NULL);
> + }
> + else
> + _mesa_reference_framebuffer(&ctx->ReadBuffer, NULL);
> +
> + /* update state */
> + ctx->NewState |= _NEW_BUFFERS;
> + _mesa_update_state( ctx );
> +}
> +
> +/**
> + * Plug in draw function to draw in GL_SELECT mode.
> + * This function does the following steps:
> + * 1) render into the 1st pixel of our FBO with depth state
> + * configured so that we get the lowest Z values
> + * 2) render into the 2nd pixel of our FBO with depth state
> + * configured so that we get the highest Z values
> + * 3) calls st_select_emul_update_hits() to emit results
> + */
> +void
> +st_select_draw_func(struct gl_context *ctx,
> + const struct gl_client_array **arrays,
> + const struct _mesa_prim *prims,
> + GLuint nr_prims,
> + const struct _mesa_index_buffer *ib,
> + GLboolean index_bounds_valid,
> + GLuint min_index,
> + GLuint max_index)
> +{
> + GLboolean saved_scissorEnabled;
> + struct gl_framebuffer *saved_fbo = NULL;
> + struct st_context *st = st_context(ctx);
> + struct pipe_depth_stencil_alpha_state state_depth;
> + struct pipe_viewport_state state_viewport;
> +
> + /* save states */
> + if (ctx->DrawBuffer)
> + _mesa_reference_framebuffer(&saved_fbo, ctx->DrawBuffer);
> +
> + saved_scissorEnabled = ctx->Scissor.Enabled;
> + cso_save_fragment_shader(st->cso_context);
> + cso_save_depth_stencil_alpha(st->cso_context);
> + cso_save_viewport(st->cso_context);
> +
> + /* prepare stencil state */
> + memset(&state_depth, 0, sizeof(state_depth));
> + state_depth.depth.enabled = 1;
> + state_depth.depth.writemask = 1;
> +
> + /* prepare viewport state */
> + memset(&state_viewport, 0, sizeof(state_viewport));
> + state_viewport.scale[0] = 0.5f * 2.0f * 0.5;
> + state_viewport.scale[1] = 0.5f * 1.0f;
> + state_viewport.scale[2] = 1.0f;
> + state_viewport.scale[3] = 1.0f;
> + state_viewport.translate[1] = 0.5f * 1.0f;
> + state_viewport.translate[2] = 0.0f;
> + state_viewport.translate[3] = 0.0f;
> +
> + /* use our custom fragment shader */
> + cso_set_fragment_shader_handle(st->cso_context, st->select_emul.fs);
> +
> + /* disable scissor */
> + ctx->Scissor.Enabled = GL_FALSE;
> +
> + /* disable old draw fbo */
> + if (saved_fbo)
> + _mesa_check_end_texture_render(ctx, saved_fbo);
> +
> + /* use our fbo */
> + _mesa_check_begin_texture_render(ctx, st->select_emul.fbo);
> + _mesa_reference_framebuffer(&ctx->DrawBuffer, st->select_emul.fbo);
> +
> + /* update fbo */
> + _mesa_update_framebuffer( ctx );
> +
> + /* update context */
> + _mesa_update_state(ctx);
> +
> + /* render min-z */
> + {
> + /* specific states */
> + state_depth.depth.func = PIPE_FUNC_LESS;
> + state_viewport.translate[0] = 0.5f * 1.0f + 0.0f;
> +
> + cso_set_depth_stencil_alpha(st->cso_context, &state_depth);
> + cso_set_viewport(st->cso_context, &state_viewport);
> +
> + /* draw */
> + st_draw_vbo(ctx, arrays, prims, nr_prims, ib, index_bounds_valid,
> min_index, max_index);
> + }
> +
> + /* render max-z */
> + {
> + state_depth.depth.func = PIPE_FUNC_GREATER;
> + state_viewport.translate[0] = 0.5f * 1.0f + 1.0f;
> +
> + cso_set_depth_stencil_alpha(st->cso_context, &state_depth);
> + cso_set_viewport(st->cso_context, &state_viewport);
> +
> + /* draw */
> + st_draw_vbo(ctx, arrays, prims, nr_prims, ib, index_bounds_valid,
> min_index, max_index);
> + }
> +
> + /* XXX: needs flushing? */
> +
> + /* restore states */
> + cso_restore_fragment_shader(st->cso_context);
> + cso_restore_depth_stencil_alpha(st->cso_context);
> + cso_restore_viewport(st->cso_context);
> + ctx->Scissor.Enabled = saved_scissorEnabled;
> + _mesa_check_end_texture_render(ctx, st->select_emul.fbo);
> + if (saved_fbo) {
> + _mesa_check_begin_texture_render(ctx, saved_fbo);
> + _mesa_reference_framebuffer(&ctx->DrawBuffer, saved_fbo);
> + _mesa_reference_framebuffer(&saved_fbo, NULL);
> + }
> + else
> + _mesa_reference_framebuffer(&ctx->DrawBuffer, NULL);
> + _mesa_update_state(ctx);
> +
> + /* update hits */
> + st_select_emul_update_hits(ctx);
> +}
> +
> --
> 1.7.6
>
>
--
Micael Dias
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