Workbench: Depth Of Field: Improve noise and Large radius

- Add noise to remove undersampling artifact
- Create 2 mipmaps to the scene color buffer in order to have bigger blurs
- Replace blur2 with a 3x3 median filter that doesn't dilate the highlights
- Use temporal accumulation to remove noise

For some reason all of this exacerbate some bleeding issues happening on
far foreground elements from near foreground elements. The actual problem
was already happening before but was not really noticeable. It needs some
more work to be fixed.

1 files changed, 38 insertions, 11 deletions

diff --git a/source/blender/draw/engines/workbench/workbench_effect_dof.c b/source/blender/draw/engines/workbench/workbench_effect_dof.c
index ec8c184eac5..85bb5ba0522 100644
--- a/source/blender/draw/engines/workbench/workbench_effect_dof.c
+++ b/source/blender/draw/engines/workbench/workbench_effect_dof.c
@@ -33,6 +33,7 @@
 /* *********** STATIC *********** */
 static struct {
 	struct GPUShader *effect_dof_prepare_sh;
+	struct GPUShader *effect_dof_downsample_sh;
 	struct GPUShader *effect_dof_flatten_v_sh;
 	struct GPUShader *effect_dof_flatten_h_sh;
 	struct GPUShader *effect_dof_dilate_v_sh;
@@ -130,6 +131,7 @@ static void workbench_dof_setup_samples(
 
 void workbench_dof_engine_init(WORKBENCH_Data *vedata, Object *camera)
 {
+	WORKBENCH_TextureList *txl = vedata->txl;
 	WORKBENCH_StorageList *stl = vedata->stl;
 	WORKBENCH_PrivateData *wpd = stl->g_data;
 	WORKBENCH_FramebufferList *fbl = vedata->fbl;
@@ -146,6 +148,10 @@ void workbench_dof_engine_init(WORKBENCH_Data *vedata, Object *camera)
 		        datatoc_workbench_effect_dof_frag_glsl,
 		        "#define PREPARE\n");
 
+		e_data.effect_dof_downsample_sh = DRW_shader_create_fullscreen(
+		        datatoc_workbench_effect_dof_frag_glsl,
+		        "#define DOWNSAMPLE\n");
+
 		e_data.effect_dof_flatten_v_sh = DRW_shader_create_fullscreen(
 		        datatoc_workbench_effect_dof_frag_glsl,
 		        "#define FLATTEN_VERTICAL\n");
@@ -183,9 +189,9 @@ void workbench_dof_engine_init(WORKBENCH_Data *vedata, Object *camera)
 	int shrink_w_size[2] = {shrink_h_size[0], ceilf(size[1] / 8.0f)};
 #endif
 
-	wpd->half_res_col_tx = DRW_texture_pool_query_2D(size[0], size[1], GPU_R11F_G11F_B10F, &draw_engine_workbench_solid);
+	DRW_texture_ensure_2D(&txl->dof_source_tx, size[0], size[1], GPU_R11F_G11F_B10F, DRW_TEX_FILTER | DRW_TEX_MIPMAP);
+	DRW_texture_ensure_2D(&txl->coc_halfres_tx, size[0], size[1], GPU_RG8, DRW_TEX_FILTER | DRW_TEX_MIPMAP);
 	wpd->dof_blur_tx = DRW_texture_pool_query_2D(size[0], size[1], GPU_R11F_G11F_B10F, &draw_engine_workbench_solid);
-	wpd->coc_halfres_tx  = DRW_texture_pool_query_2D(size[0], size[1], GPU_RG8, &draw_engine_workbench_solid);
 #if 0
 	wpd->coc_temp_tx     = DRW_texture_pool_query_2D(shrink_h_size[0], shrink_h_size[1], GPU_RG8, &draw_engine_workbench_solid);
 	wpd->coc_tiles_tx[0] = DRW_texture_pool_query_2D(shrink_w_size[0], shrink_w_size[1], GPU_RG8, &draw_engine_workbench_solid);
@@ -194,8 +200,8 @@ void workbench_dof_engine_init(WORKBENCH_Data *vedata, Object *camera)
 
 	GPU_framebuffer_ensure_config(&fbl->dof_downsample_fb, {
 		GPU_ATTACHMENT_NONE,
-		GPU_ATTACHMENT_TEXTURE(wpd->half_res_col_tx),
-		GPU_ATTACHMENT_TEXTURE(wpd->coc_halfres_tx),
+		GPU_ATTACHMENT_TEXTURE(txl->dof_source_tx),
+		GPU_ATTACHMENT_TEXTURE(txl->coc_halfres_tx),
 	});
 #if 0
 	GPU_framebuffer_ensure_config(&fbl->dof_coc_tile_h_fb, {
@@ -217,7 +223,7 @@ void workbench_dof_engine_init(WORKBENCH_Data *vedata, Object *camera)
 	});
 	GPU_framebuffer_ensure_config(&fbl->dof_blur2_fb, {
 		GPU_ATTACHMENT_NONE,
-		GPU_ATTACHMENT_TEXTURE(wpd->half_res_col_tx),
+		GPU_ATTACHMENT_TEXTURE(txl->dof_source_tx),
 	});
 
 	{
@@ -276,9 +282,10 @@ void workbench_dof_engine_init(WORKBENCH_Data *vedata, Object *camera)
 	wpd->dof_enabled = true;
 }
 
-void workbench_dof_create_pass(WORKBENCH_Data *vedata, GPUTexture **dof_input)
+void workbench_dof_create_pass(WORKBENCH_Data *vedata, GPUTexture **dof_input, GPUTexture *noise_tex)
 {
 	WORKBENCH_PassList *psl = vedata->psl;
+	WORKBENCH_TextureList *txl = vedata->txl;
 	WORKBENCH_StorageList *stl = vedata->stl;
 	WORKBENCH_PrivateData *wpd = stl->g_data;
 	struct GPUBatch *quad = DRW_cache_fullscreen_quad_get();
@@ -290,6 +297,7 @@ void workbench_dof_create_pass(WORKBENCH_Data *vedata, GPUTexture **dof_input)
 	DefaultTextureList *dtxl = DRW_viewport_texture_list_get();
 
 	psl->dof_down_ps = DRW_pass_create("DoF DownSample", DRW_STATE_WRITE_COLOR);
+	psl->dof_down2_ps = DRW_pass_create("DoF DownSample", DRW_STATE_WRITE_COLOR);
 	psl->dof_flatten_h_ps = DRW_pass_create("DoF Flatten Coc H", DRW_STATE_WRITE_COLOR);
 	psl->dof_flatten_v_ps = DRW_pass_create("DoF Flatten Coc V", DRW_STATE_WRITE_COLOR);
 	psl->dof_dilate_h_ps = DRW_pass_create("DoF Dilate Coc H", DRW_STATE_WRITE_COLOR);
@@ -307,10 +315,17 @@ void workbench_dof_create_pass(WORKBENCH_Data *vedata, GPUTexture **dof_input)
 		DRW_shgroup_uniform_vec2(grp, "nearFar", wpd->dof_near_far, 1);
 		DRW_shgroup_call_add(grp, quad, NULL);
 	}
+
+	{
+		DRWShadingGroup *grp = DRW_shgroup_create(e_data.effect_dof_downsample_sh, psl->dof_down2_ps);
+		DRW_shgroup_uniform_texture(grp, "sceneColorTex", txl->dof_source_tx);
+		DRW_shgroup_uniform_texture(grp, "inputCocTex", txl->coc_halfres_tx);
+		DRW_shgroup_call_add(grp, quad, NULL);
+	}
 #if 0
 	{
 		DRWShadingGroup *grp = DRW_shgroup_create(e_data.effect_dof_flatten_h_sh, psl->dof_flatten_h_ps);
-		DRW_shgroup_uniform_texture(grp, "inputCocTex", wpd->coc_halfres_tx);
+		DRW_shgroup_uniform_texture(grp, "inputCocTex", txl->coc_halfres_tx);
 		DRW_shgroup_call_add(grp, quad, NULL);
 	}
 	{
@@ -330,23 +345,26 @@ void workbench_dof_create_pass(WORKBENCH_Data *vedata, GPUTexture **dof_input)
 	}
 #endif
 	{
+		float offset = stl->effects->jitter_index / (float)workbench_taa_calculate_num_iterations(vedata);
 		DRWShadingGroup *grp = DRW_shgroup_create(e_data.effect_dof_blur1_sh, psl->dof_blur1_ps);
 		DRW_shgroup_uniform_block(grp, "dofSamplesBlock", wpd->dof_ubo);
-		DRW_shgroup_uniform_texture(grp, "inputCocTex", wpd->coc_halfres_tx);
-		DRW_shgroup_uniform_texture(grp, "halfResColorTex", wpd->half_res_col_tx);
+		DRW_shgroup_uniform_texture(grp, "noiseTex", noise_tex);
+		DRW_shgroup_uniform_texture(grp, "inputCocTex", txl->coc_halfres_tx);
+		DRW_shgroup_uniform_texture(grp, "halfResColorTex", txl->dof_source_tx);
 		DRW_shgroup_uniform_vec2(grp, "invertedViewportSize", DRW_viewport_invert_size_get(), 1);
+		DRW_shgroup_uniform_float_copy(grp, "noiseOffset", offset);
 		DRW_shgroup_call_add(grp, quad, NULL);
 	}
 	{
 		DRWShadingGroup *grp = DRW_shgroup_create(e_data.effect_dof_blur2_sh, psl->dof_blur2_ps);
-		DRW_shgroup_uniform_texture(grp, "inputCocTex", wpd->coc_halfres_tx);
+		DRW_shgroup_uniform_texture(grp, "inputCocTex", txl->coc_halfres_tx);
 		DRW_shgroup_uniform_texture(grp, "blurTex", wpd->dof_blur_tx);
 		DRW_shgroup_uniform_vec2(grp, "invertedViewportSize", DRW_viewport_invert_size_get(), 1);
 		DRW_shgroup_call_add(grp, quad, NULL);
 	}
 	{
 		DRWShadingGroup *grp = DRW_shgroup_create(e_data.effect_dof_resolve_sh, psl->dof_resolve_ps);
-		DRW_shgroup_uniform_texture(grp, "halfResColorTex", wpd->half_res_col_tx);
+		DRW_shgroup_uniform_texture(grp, "halfResColorTex", txl->dof_source_tx);
 		DRW_shgroup_uniform_texture(grp, "sceneDepthTex", dtxl->depth);
 		DRW_shgroup_uniform_vec2(grp, "invertedViewportSize", DRW_viewport_invert_size_get(), 1);
 		DRW_shgroup_uniform_vec3(grp, "dofParams", &wpd->dof_aperturesize, 1);
@@ -358,6 +376,7 @@ void workbench_dof_create_pass(WORKBENCH_Data *vedata, GPUTexture **dof_input)
 void workbench_dof_engine_free(void)
 {
 	DRW_SHADER_FREE_SAFE(e_data.effect_dof_prepare_sh);
+	DRW_SHADER_FREE_SAFE(e_data.effect_dof_downsample_sh);
 	DRW_SHADER_FREE_SAFE(e_data.effect_dof_flatten_v_sh);
 	DRW_SHADER_FREE_SAFE(e_data.effect_dof_flatten_h_sh);
 	DRW_SHADER_FREE_SAFE(e_data.effect_dof_dilate_v_sh);
@@ -367,6 +386,12 @@ void workbench_dof_engine_free(void)
 	DRW_SHADER_FREE_SAFE(e_data.effect_dof_resolve_sh);
 }
 
+static void workbench_dof_downsample_level(void *userData, int UNUSED(level))
+{
+	WORKBENCH_PassList *psl = (WORKBENCH_PassList *)userData;
+	DRW_draw_pass(psl->dof_down2_ps);
+}
+
 void workbench_dof_draw_pass(WORKBENCH_Data *vedata)
 {
 	WORKBENCH_FramebufferList *fbl = vedata->fbl;
@@ -383,6 +408,8 @@ void workbench_dof_draw_pass(WORKBENCH_Data *vedata)
 	GPU_framebuffer_bind(fbl->dof_downsample_fb);
 	DRW_draw_pass(psl->dof_down_ps);
 
+	GPU_framebuffer_recursive_downsample(fbl->dof_downsample_fb, 2, workbench_dof_downsample_level, psl);
+
 #if 0
 	GPU_framebuffer_bind(fbl->dof_coc_tile_h_fb);
 	DRW_draw_pass(psl->dof_flatten_h_ps);