[Bf-blender-cvs] [fa010ddddac] draw-colormanagement: DRW: Use Batch API instead of IMM for color managment

[Clément Foucault]

Commit: fa010ddddac81af1e0e6422c7066461799361a39
Author: Clément Foucault
Date:   Wed Jan 22 16:59:26 2020 +0100
Branches: draw-colormanagement
https://developer.blender.org/rBfa010ddddac81af1e0e6422c7066461799361a39

DRW: Use Batch API instead of IMM for color managment

A little cleanup that should avoid some state changes and pipeline stall.

===================================================================

M	source/blender/draw/intern/draw_manager.c
M	source/blender/gpu/GPU_batch.h
M	source/blender/gpu/intern/gpu_batch.c
M	source/blender/gpu/intern/gpu_immediate.c
M	source/blender/gpu/intern/gpu_shader_private.h

===================================================================

diff --git a/source/blender/draw/intern/draw_manager.c b/source/blender/draw/intern/draw_manager.c
index 2fbb0a740cf..99dc640158a 100644
--- a/source/blender/draw/intern/draw_manager.c
+++ b/source/blender/draw/intern/draw_manager.c
@@ -271,14 +271,15 @@ void DRW_transform_to_display(GPUTexture *tex, bool use_view_transform, bool use
 {
   drw_state_set(DRW_STATE_WRITE_COLOR);
 
-  GPUVertFormat *vert_format = immVertexFormat();
-  uint pos = GPU_vertformat_attr_add(vert_format, "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);
-  uint texco = GPU_vertformat_attr_add(vert_format, "texCoord", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);
+  GPUBatch *geom = DRW_cache_fullscreen_quad_get();
 
   const float dither = 1.0f;
 
   bool use_ocio = false;
 
+  GPU_matrix_identity_set();
+  GPU_matrix_identity_projection_set();
+
   /* Should we apply the view transform */
   if (DRW_state_do_color_management()) {
     Scene *scene = DST.draw_ctx.scene;
@@ -305,44 +306,26 @@ void DRW_transform_to_display(GPUTexture *tex, bool use_view_transform, bool use
         &view_settings, display_settings, NULL, dither, false);
   }
 
-  if (!use_ocio) {
+  if (use_ocio) {
+    GPU_batch_program_set_imm_shader(geom);
+    /* End IMM session. */
+    IMB_colormanagement_finish_glsl_draw();
+  }
+  else {
     /* View transform is already applied for offscreen, don't apply again, see: T52046 */
     if (DST.options.is_image_render && !DST.options.is_scene_render) {
-      immBindBuiltinProgram(GPU_SHADER_2D_IMAGE_COLOR);
-      immUniformColor4f(1.0f, 1.0f, 1.0f, 1.0f);
+      GPU_batch_program_set_builtin(geom, GPU_SHADER_2D_IMAGE_COLOR);
+      GPU_batch_uniform_4f(geom, "color", 1.0f, 1.0f, 1.0f, 1.0f);
     }
     else {
-      immBindBuiltinProgram(GPU_SHADER_2D_IMAGE_LINEAR_TO_SRGB);
+      GPU_batch_program_set_builtin(geom, GPU_SHADER_2D_IMAGE_LINEAR_TO_SRGB);
     }
-    immUniform1i("image", 0);
+    GPU_batch_uniform_1i(geom, "image", 0);
   }
 
   GPU_texture_bind(tex, 0); /* OCIO texture bind point is 0 */
-
-  float mat[4][4];
-  unit_m4(mat);
-  immUniformMatrix4fv("ModelViewProjectionMatrix", mat);
-
-  /* Full screen triangle */
-  immBegin(GPU_PRIM_TRIS, 3);
-  immAttr2f(texco, 0.0f, 0.0f);
-  immVertex2f(pos, -1.0f, -1.0f);
-
-  immAttr2f(texco, 2.0f, 0.0f);
-  immVertex2f(pos, 3.0f, -1.0f);
-
-  immAttr2f(texco, 0.0f, 2.0f);
-  immVertex2f(pos, -1.0f, 3.0f);
-  immEnd();
-
+  GPU_batch_draw(geom);
   GPU_texture_unbind(tex);
-
-  if (use_ocio) {
-    IMB_colormanagement_finish_glsl_draw();
-  }
-  else {
-    immUnbindProgram();
-  }
 }
 
 /* Draw texture to framebuffer without any color transforms */
diff --git a/source/blender/gpu/GPU_batch.h b/source/blender/gpu/GPU_batch.h
index 3616189e673..fc7dff5d99b 100644
--- a/source/blender/gpu/GPU_batch.h
+++ b/source/blender/gpu/GPU_batch.h
@@ -126,6 +126,7 @@ int GPU_batch_vertbuf_add_ex(GPUBatch *, GPUVertBuf *, bool own_vbo);
 void GPU_batch_program_set_no_use(GPUBatch *, uint32_t program, const GPUShaderInterface *);
 void GPU_batch_program_set(GPUBatch *, uint32_t program, const GPUShaderInterface *);
 void GPU_batch_program_set_shader(GPUBatch *, GPUShader *shader);
+void GPU_batch_program_set_imm_shader(GPUBatch *batch);
 void GPU_batch_program_set_builtin(GPUBatch *batch, eGPUBuiltinShader shader_id);
 void GPU_batch_program_set_builtin_with_config(GPUBatch *batch,
                                                eGPUBuiltinShader shader_id,
diff --git a/source/blender/gpu/intern/gpu_batch.c b/source/blender/gpu/intern/gpu_batch.c
index 717983f94d8..c20fc2172d1 100644
--- a/source/blender/gpu/intern/gpu_batch.c
+++ b/source/blender/gpu/intern/gpu_batch.c
@@ -982,6 +982,17 @@ void GPU_batch_program_set_builtin(GPUBatch *batch, eGPUBuiltinShader shader_id)
   GPU_batch_program_set_builtin_with_config(batch, shader_id, GPU_SHADER_CFG_DEFAULT);
 }
 
+/* Bind program bound to IMM to the batch.
+ * XXX Use this with much care. Drawing with the GPUBatch API is not compatible with IMM.
+ * DO NOT DRAW WITH THE BATCH BEFORE CALLING immUnbindProgram. */
+void GPU_batch_program_set_imm_shader(GPUBatch *batch)
+{
+  GLuint program;
+  GPUShaderInterface *interface;
+  immGetProgram(&program, &interface);
+  GPU_batch_program_set(batch, program, interface);
+}
+
 /** \} */
 
 /* -------------------------------------------------------------------- */
diff --git a/source/blender/gpu/intern/gpu_immediate.c b/source/blender/gpu/intern/gpu_immediate.c
index bed7ab25bb9..bd3de96d636 100644
--- a/source/blender/gpu/intern/gpu_immediate.c
+++ b/source/blender/gpu/intern/gpu_immediate.c
@@ -168,6 +168,13 @@ void immUnbindProgram(void)
   imm.bound_program = 0;
 }
 
+/* XXX do not use it. Special hack to use OCIO with batch API. */
+void immGetProgram(GLuint *program, GPUShaderInterface **shaderface)
+{
+  *program = imm.bound_program;
+  *shaderface = (GPUShaderInterface *)imm.shader_interface;
+}
+
 #if TRUST_NO_ONE
 static bool vertex_count_makes_sense_for_primitive(uint vertex_len, GPUPrimType prim_type)
 {
diff --git a/source/blender/gpu/intern/gpu_shader_private.h b/source/blender/gpu/intern/gpu_shader_private.h
index 856a14c6868..e4443e79a8d 100644
--- a/source/blender/gpu/intern/gpu_shader_private.h
+++ b/source/blender/gpu/intern/gpu_shader_private.h
@@ -44,4 +44,7 @@ struct GPUShader {
 #endif
 };
 
+/* XXX do not use it. Special hack to use OCIO with batch API. */
+void immGetProgram(GLuint *program, GPUShaderInterface **shaderface);
+
 #endif /* __GPU_SHADER_PRIVATE_H__ */