DRW: Add new features from lightcache branch

- Change gl_context_mutex to a ticket mutex ensuring interactivity even
  when rendering.
- Add DRW_custom_pipeline for using DRW outside of the viewport and render
  pipeline.
- DRW_opengl_render_context_*** and DRW_gawain_render_context_*** to use
  with DRW_custom_pipeline.
- Add possibility to bypass deferred compilation on demand (not User
  demand).
- Add union to access DRWMatrixState members more easily.

6 files changed, 150 insertions, 49 deletions

diff --git a/source/blender/draw/DRW_engine.h b/source/blender/draw/DRW_engine.h
index d2a3bab9b20..ab2001dcb6a 100644
--- a/source/blender/draw/DRW_engine.h
+++ b/source/blender/draw/DRW_engine.h
@@ -136,6 +136,11 @@ void DRW_opengl_context_destroy(void);
 void DRW_opengl_context_enable(void);
 void DRW_opengl_context_disable(void);
 
+void DRW_opengl_render_context_enable(void *re_gl_context);
+void DRW_opengl_render_context_disable(void *re_gl_context);
+void DRW_gawain_render_context_enable(void *re_gwn_context);
+void DRW_gawain_render_context_disable(void *re_gwn_context);
+
 void DRW_deferred_shader_remove(struct GPUMaterial *mat);
 
 struct DrawDataList *DRW_drawdatalist_from_id(struct ID *id);
diff --git a/source/blender/draw/engines/eevee/eevee_materials.c b/source/blender/draw/engines/eevee/eevee_materials.c
index 4161d11e0c1..4a7e97756a9 100644
--- a/source/blender/draw/engines/eevee/eevee_materials.c
+++ b/source/blender/draw/engines/eevee/eevee_materials.c
@@ -654,14 +654,14 @@ struct GPUMaterial *EEVEE_material_world_lightprobe_get(struct Scene *scene, Wor
 	const void *engine = &DRW_engine_viewport_eevee_type;
 	const int options = VAR_WORLD_PROBE;
 
-	GPUMaterial *mat = DRW_shader_find_from_world(wo, engine, options);
+	GPUMaterial *mat = DRW_shader_find_from_world(wo, engine, options, false);
 	if (mat != NULL) {
 		return mat;
 	}
 	return DRW_shader_create_from_world(
 	        scene, wo, engine, options,
 	        datatoc_background_vert_glsl, NULL, e_data.frag_shader_lib,
-	        SHADER_DEFINES "#define PROBE_CAPTURE\n");
+	        SHADER_DEFINES "#define PROBE_CAPTURE\n", false);
 }
 
 struct GPUMaterial *EEVEE_material_world_background_get(struct Scene *scene, World *wo)
@@ -669,14 +669,14 @@ struct GPUMaterial *EEVEE_material_world_background_get(struct Scene *scene, Wor
 	const void *engine = &DRW_engine_viewport_eevee_type;
 	int options = VAR_WORLD_BACKGROUND;
 
-	GPUMaterial *mat = DRW_shader_find_from_world(wo, engine, options);
+	GPUMaterial *mat = DRW_shader_find_from_world(wo, engine, options, true);
 	if (mat != NULL) {
 		return mat;
 	}
 	return DRW_shader_create_from_world(
 	        scene, wo, engine, options,
 	        datatoc_background_vert_glsl, NULL, e_data.frag_shader_lib,
-	        SHADER_DEFINES "#define WORLD_BACKGROUND\n");
+	        SHADER_DEFINES "#define WORLD_BACKGROUND\n", true);
 }
 
 struct GPUMaterial *EEVEE_material_world_volume_get(struct Scene *scene, World *wo)
@@ -684,7 +684,7 @@ struct GPUMaterial *EEVEE_material_world_volume_get(struct Scene *scene, World *
 	const void *engine = &DRW_engine_viewport_eevee_type;
 	int options = VAR_WORLD_VOLUME;
 
-	GPUMaterial *mat = DRW_shader_find_from_world(wo, engine, options);
+	GPUMaterial *mat = DRW_shader_find_from_world(wo, engine, options, true);
 	if (mat != NULL) {
 		return mat;
 	}
@@ -694,7 +694,7 @@ struct GPUMaterial *EEVEE_material_world_volume_get(struct Scene *scene, World *
 	mat = DRW_shader_create_from_world(
 	        scene, wo, engine, options,
 	        datatoc_volumetric_vert_glsl, datatoc_volumetric_geom_glsl, e_data.volume_shader_lib,
-	        defines);
+	        defines, true);
 
 	MEM_freeN(defines);
 
@@ -719,7 +719,7 @@ struct GPUMaterial *EEVEE_material_mesh_get(
 
 	options |= eevee_material_shadow_option(shadow_method);
 
-	GPUMaterial *mat = DRW_shader_find_from_material(ma, engine, options);
+	GPUMaterial *mat = DRW_shader_find_from_material(ma, engine, options, true);
 	if (mat) {
 		return mat;
 	}
@@ -729,7 +729,7 @@ struct GPUMaterial *EEVEE_material_mesh_get(
 	mat = DRW_shader_create_from_material(
 	        scene, ma, engine, options,
 	        e_data.vert_shader_str, NULL, e_data.frag_shader_lib,
-	        defines);
+	        defines, true);
 
 	MEM_freeN(defines);
 
@@ -741,7 +741,7 @@ struct GPUMaterial *EEVEE_material_mesh_volume_get(struct Scene *scene, Material
 	const void *engine = &DRW_engine_viewport_eevee_type;
 	int options = VAR_MAT_VOLUME;
 
-	GPUMaterial *mat = DRW_shader_find_from_material(ma, engine, options);
+	GPUMaterial *mat = DRW_shader_find_from_material(ma, engine, options, true);
 	if (mat != NULL) {
 		return mat;
 	}
@@ -751,7 +751,7 @@ struct GPUMaterial *EEVEE_material_mesh_volume_get(struct Scene *scene, Material
 	mat = DRW_shader_create_from_material(
 	        scene, ma, engine, options,
 	        datatoc_volumetric_vert_glsl, datatoc_volumetric_geom_glsl, e_data.volume_shader_lib,
-	        defines);
+	        defines, true);
 
 	MEM_freeN(defines);
 
@@ -775,7 +775,7 @@ struct GPUMaterial *EEVEE_material_mesh_depth_get(
 	if (is_shadow)
 		options |= VAR_MAT_SHADOW;
 
-	GPUMaterial *mat = DRW_shader_find_from_material(ma, engine, options);
+	GPUMaterial *mat = DRW_shader_find_from_material(ma, engine, options, true);
 	if (mat) {
 		return mat;
 	}
@@ -791,7 +791,8 @@ struct GPUMaterial *EEVEE_material_mesh_depth_get(
 	        (is_shadow) ? datatoc_shadow_vert_glsl : e_data.vert_shader_str,
 	        NULL,
 	        frag_str,
-	        defines);
+	        defines,
+	        true);
 
 	MEM_freeN(frag_str);
 	MEM_freeN(defines);
@@ -807,7 +808,7 @@ struct GPUMaterial *EEVEE_material_hair_get(
 
 	options |= eevee_material_shadow_option(shadow_method);
 
-	GPUMaterial *mat = DRW_shader_find_from_material(ma, engine, options);
+	GPUMaterial *mat = DRW_shader_find_from_material(ma, engine, options, true);
 	if (mat) {
 		return mat;
 	}
@@ -817,7 +818,7 @@ struct GPUMaterial *EEVEE_material_hair_get(
 	mat = DRW_shader_create_from_material(
 	        scene, ma, engine, options,
 	        e_data.vert_shader_str, NULL, e_data.frag_shader_lib,
-	        defines);
+	        defines, true);
 
 	MEM_freeN(defines);
 
diff --git a/source/blender/draw/intern/DRW_render.h b/source/blender/draw/intern/DRW_render.h
index e0c8cb36e2f..4d1b8269494 100644
--- a/source/blender/draw/intern/DRW_render.h
+++ b/source/blender/draw/intern/DRW_render.h
@@ -240,14 +240,14 @@ struct GPUShader *DRW_shader_create_2D(const char *frag, const char *defines);
 struct GPUShader *DRW_shader_create_3D(const char *frag, const char *defines);
 struct GPUShader *DRW_shader_create_fullscreen(const char *frag, const char *defines);
 struct GPUShader *DRW_shader_create_3D_depth_only(void);
-struct GPUMaterial *DRW_shader_find_from_world(struct World *wo, const void *engine_type, int options);
-struct GPUMaterial *DRW_shader_find_from_material(struct Material *ma, const void *engine_type, int options);
+struct GPUMaterial *DRW_shader_find_from_world(struct World *wo, const void *engine_type, int options, bool no_deferred);
+struct GPUMaterial *DRW_shader_find_from_material(struct Material *ma, const void *engine_type, int options, bool no_deferred);
 struct GPUMaterial *DRW_shader_create_from_world(
         struct Scene *scene, struct World *wo, const void *engine_type, int options,
-        const char *vert, const char *geom, const char *frag_lib, const char *defines);
+        const char *vert, const char *geom, const char *frag_lib, const char *defines, bool no_deferred);
 struct GPUMaterial *DRW_shader_create_from_material(
         struct Scene *scene, struct Material *ma, const void *engine_type, int options,
-        const char *vert, const char *geom, const char *frag_lib, const char *defines);
+        const char *vert, const char *geom, const char *frag_lib, const char *defines, bool no_deferred);
 void DRW_shader_free(struct GPUShader *shader);
 #define DRW_SHADER_FREE_SAFE(shader) do { \
 	if (shader != NULL) { \
@@ -410,6 +410,7 @@ void DRW_pass_sort_shgroup_z(DRWPass *pass);
 
 /* Viewport */
 typedef enum {
+	/* keep in sync with the union struct DRWMatrixState. */
 	DRW_MAT_PERS = 0,
 	DRW_MAT_PERSINV,
 	DRW_MAT_VIEW,
@@ -421,7 +422,18 @@ typedef enum {
 } DRWViewportMatrixType;
 
 typedef struct DRWMatrixState {
-	float mat[DRW_MAT_COUNT][4][4];
+	union {
+		float mat[DRW_MAT_COUNT][4][4];
+		struct {
+			/* keep in sync with the enum DRWViewportMatrixType. */
+			float persmat[4][4];
+			float persinv[4][4];
+			float viewmat[4][4];
+			float viewinv[4][4];
+			float winmat[4][4];
+			float wininv[4][4];
+		};
+	};
 } DRWMatrixState;
 
 void DRW_viewport_init(const bContext *C);
@@ -454,6 +466,12 @@ void DRW_render_object_iter(
 	void (*callback)(void *vedata, struct Object *ob, struct RenderEngine *engine, struct Depsgraph *depsgraph));
 void DRW_render_instance_buffer_finish(void);
 
+void DRW_custom_pipeline(
+        DrawEngineType *draw_engine_type,
+        struct Depsgraph *depsgraph,
+        void (*callback)(void *vedata, void *user_data),
+        void *user_data);
+
 /* ViewLayers */
 void *DRW_view_layer_engine_data_get(DrawEngineType *engine_type);
 void **DRW_view_layer_engine_data_ensure_ex(
diff --git a/source/blender/draw/intern/draw_manager.c b/source/blender/draw/intern/draw_manager.c
index 311a223dcdd..30f7742fd35 100644
--- a/source/blender/draw/intern/draw_manager.c
+++ b/source/blender/draw/intern/draw_manager.c
@@ -1256,7 +1256,7 @@ void DRW_notify_view_update(const DRWUpdateContext *update_ctx)
 		/* XXX Really nasty locking. But else this could
 		 * be executed by the material previews thread
 		 * while rendering a viewport. */
-		BLI_mutex_lock(&DST.gl_context_mutex);
+		BLI_ticket_mutex_lock(DST.gl_context_mutex);
 
 		/* Reset before using it. */
 		drw_state_prepare_clean_for_draw(&DST);
@@ -1284,7 +1284,7 @@ void DRW_notify_view_update(const DRWUpdateContext *update_ctx)
 
 		drw_engines_disable();
 
-		BLI_mutex_unlock(&DST.gl_context_mutex);
+		BLI_ticket_mutex_unlock(DST.gl_context_mutex);
 	}
 }
 
@@ -1554,14 +1554,10 @@ void DRW_render_to_image(RenderEngine *engine, struct Depsgraph *depsgraph)
 
 	/* Changing Context */
 	if (re_gl_context != NULL) {
-		/* TODO get rid of the blocking. Only here because of the static global DST. */
-		BLI_mutex_lock(&DST.gl_context_mutex);
-		WM_opengl_context_activate(re_gl_context);
+		DRW_opengl_render_context_enable(re_gl_context);
+		/* We need to query gwn context after a gl context has been bound. */
 		re_gwn_context = RE_gwn_context_get(render);
-		if (GWN_context_active_get() == NULL) {
-			GWN_context_active_set(re_gwn_context);
-		}
-		DRW_shape_cache_reset(); /* XXX fix that too. */
+		DRW_gawain_render_context_enable(re_gwn_context);
 	}
 	else {
 		DRW_opengl_context_enable();
@@ -1640,12 +1636,8 @@ void DRW_render_to_image(RenderEngine *engine, struct Depsgraph *depsgraph)
 
 	/* Changing Context */
 	if (re_gl_context != NULL) {
-		DRW_shape_cache_reset(); /* XXX fix that too. */
-		glFlush();
-		GWN_context_active_set(NULL);
-		WM_opengl_context_release(re_gl_context);
-		/* TODO get rid of the blocking. */
-		BLI_mutex_unlock(&DST.gl_context_mutex);
+		DRW_gawain_render_context_disable(re_gwn_context);
+		DRW_opengl_render_context_disable(re_gl_context);
 	}
 	else {
 		DRW_opengl_context_disable();
@@ -1671,6 +1663,56 @@ void DRW_render_object_iter(
 	DEG_OBJECT_ITER_FOR_RENDER_ENGINE_END
 }
 
+/* Assume a valid gl context is bound (and that the gl_context_mutex has been aquired).
+ * This function only setup DST and execute the given function.
+ * Warning: similar to DRW_render_to_image you cannot use default lists (dfbl & dtxl). */
+void DRW_custom_pipeline(
+        DrawEngineType *draw_engine_type,
+        struct Depsgraph *depsgraph,
+        void (*callback)(void *vedata, void *user_data),
+        void *user_data)
+{
+	Scene *scene = DEG_get_evaluated_scene(depsgraph);
+	ViewLayer *view_layer = DEG_get_evaluated_view_layer(depsgraph);
+
+	/* Reset before using it. */
+	drw_state_prepare_clean_for_draw(&DST);
+	DST.options.is_image_render = true;
+	DST.options.is_scene_render = true;
+	DST.options.draw_background = false;
+
+	DST.draw_ctx = (DRWContextState){
+	    .scene = scene,
+	    .view_layer = view_layer,
+	    .engine_type = NULL,
+	    .depsgraph = depsgraph,
+	    .object_mode = OB_MODE_OBJECT,
+	};
+	drw_context_state_init();
+
+	DST.viewport = GPU_viewport_create();
+	const int size[2] = {1, 1};
+	GPU_viewport_size_set(DST.viewport, size);
+
+	drw_viewport_var_init();
+
+	DRW_hair_init();
+
+	ViewportEngineData *data = drw_viewport_engine_data_ensure(draw_engine_type);
+
+	/* Execute the callback */
+	callback(data, user_data);
+	DST.buffer_finish_called = false;
+
+	GPU_viewport_free(DST.viewport);
+	GPU_framebuffer_restore();
+
+#ifdef DEBUG
+	/* Avoid accidental reuse. */
+	drw_state_ensure_not_reused(&DST);
+#endif
+}
+
 static struct DRWSelectBuffer {
 	struct GPUFrameBuffer *framebuffer;
 	struct GPUTexture *texture_depth;
@@ -2280,7 +2322,7 @@ void DRW_opengl_context_create(void)
 {
 	BLI_assert(DST.gl_context == NULL); /* Ensure it's called once */
 
-	BLI_mutex_init(&DST.gl_context_mutex);
+	DST.gl_context_mutex = BLI_ticket_mutex_alloc();
 	if (!G.background) {
 		immDeactivate();
 	}
@@ -2305,7 +2347,7 @@ void DRW_opengl_context_destroy(void)
 		GWN_context_active_set(DST.gwn_context);
 		GWN_context_discard(DST.gwn_context);
 		WM_opengl_context_dispose(DST.gl_context);
-		BLI_mutex_end(&DST.gl_context_mutex);
+		BLI_ticket_mutex_free(DST.gl_context_mutex);
 	}
 }
 
@@ -2315,7 +2357,7 @@ void DRW_opengl_context_enable(void)
 		/* IMPORTANT: We dont support immediate mode in render mode!
 		 * This shall remain in effect until immediate mode supports
 		 * multiple threads. */
-		BLI_mutex_lock(&DST.gl_context_mutex);
+		BLI_ticket_mutex_lock(DST.gl_context_mutex);
 		if (BLI_thread_is_main()) {
 			if (!G.background) {
 				immDeactivate();
@@ -2349,8 +2391,43 @@ void DRW_opengl_context_disable(void)
 			GWN_context_active_set(NULL);
 		}
 
-		BLI_mutex_unlock(&DST.gl_context_mutex);
+		BLI_ticket_mutex_unlock(DST.gl_context_mutex);
 	}
 }
 
+void DRW_opengl_render_context_enable(void *re_gl_context)
+{
+	/* If thread is main you should use DRW_opengl_context_enable(). */
+	BLI_assert(!BLI_thread_is_main());
+
+	/* TODO get rid of the blocking. Only here because of the static global DST. */
+	BLI_ticket_mutex_lock(DST.gl_context_mutex);
+	WM_opengl_context_activate(re_gl_context);
+}
+
+void DRW_opengl_render_context_disable(void *re_gl_context)
+{
+	glFlush();
+	WM_opengl_context_release(re_gl_context);
+	/* TODO get rid of the blocking. */
+	BLI_ticket_mutex_unlock(DST.gl_context_mutex);
+}
+
+/* Needs to be called AFTER DRW_opengl_render_context_enable() */
+void DRW_gawain_render_context_enable(void *re_gwn_context)
+{
+	/* If thread is main you should use DRW_opengl_context_enable(). */
+	BLI_assert(!BLI_thread_is_main());
+
+	GWN_context_active_set(re_gwn_context);
+	DRW_shape_cache_reset(); /* XXX fix that too. */
+}
+
+/* Needs to be called BEFORE DRW_opengl_render_context_disable() */
+void DRW_gawain_render_context_disable(void *UNUSED(re_gwn_context))
+{
+	DRW_shape_cache_reset(); /* XXX fix that too. */
+	GWN_context_active_set(NULL);
+}
+
 /** \} */
diff --git a/source/blender/draw/intern/draw_manager.h b/source/blender/draw/intern/draw_manager.h
index 91a30fa45ae..6eae3459c2b 100644
--- a/source/blender/draw/intern/draw_manager.h
+++ b/source/blender/draw/intern/draw_manager.h
@@ -373,7 +373,7 @@ typedef struct DRWManager {
 	 * the top portion of the struct so DO NOT MOVE IT! */
 	void *gl_context;                /* Unique ghost context used by the draw manager. */
 	Gwn_Context *gwn_context;
-	ThreadMutex gl_context_mutex;    /* Mutex to lock the drw manager and avoid concurent context usage. */
+	TicketMutex *gl_context_mutex;    /* Mutex to lock the drw manager and avoid concurent context usage. */
 
 	/** GPU Resource State: Memory storage between drawing. */
 	struct {
diff --git a/source/blender/draw/intern/draw_manager_shader.c b/source/blender/draw/intern/draw_manager_shader.c
index 435c6c77e59..b0aec4a7600 100644
--- a/source/blender/draw/intern/draw_manager_shader.c
+++ b/source/blender/draw/intern/draw_manager_shader.c
@@ -154,10 +154,10 @@ static void drw_deferred_shader_compilation_free(void *custom_data)
 	MEM_freeN(comp);
 }
 
-static void drw_deferred_shader_add(GPUMaterial *mat)
+static void drw_deferred_shader_add(GPUMaterial *mat, bool deferred)
 {
 	/* Do not deferre the compilation if we are rendering for image. */
-	if (DRW_state_is_image_render() || !USE_DEFERRED_COMPILATION) {
+	if (DRW_state_is_image_render() || !USE_DEFERRED_COMPILATION || !deferred) {
 		/* Double checking that this GPUMaterial is not going to be
 		 * compiled by another thread. */
 		DRW_deferred_shader_remove(mat);
@@ -308,10 +308,10 @@ GPUShader *DRW_shader_create_3D_depth_only(void)
 	return GPU_shader_get_builtin_shader(GPU_SHADER_3D_DEPTH_ONLY);
 }
 
-GPUMaterial *DRW_shader_find_from_world(World *wo, const void *engine_type, int options)
+GPUMaterial *DRW_shader_find_from_world(World *wo, const void *engine_type, int options, bool deferred)
 {
 	GPUMaterial *mat = GPU_material_from_nodetree_find(&wo->gpumaterial, engine_type, options);
-	if (DRW_state_is_image_render()) {
+	if (DRW_state_is_image_render() || !deferred) {
 		if (mat != NULL && GPU_material_status(mat) == GPU_MAT_QUEUED) {
 			/* XXX Hack : we return NULL so that the engine will call DRW_shader_create_from_XXX
 			 * with the shader code and we will resume the compilation from there. */
@@ -321,10 +321,10 @@ GPUMaterial *DRW_shader_find_from_world(World *wo, const void *engine_type, int
 	return mat;
 }
 
-GPUMaterial *DRW_shader_find_from_material(Material *ma, const void *engine_type, int options)
+GPUMaterial *DRW_shader_find_from_material(Material *ma, const void *engine_type, int options, bool deferred)
 {
 	GPUMaterial *mat = GPU_material_from_nodetree_find(&ma->gpumaterial, engine_type, options);
-	if (DRW_state_is_image_render()) {
+	if (DRW_state_is_image_render() || !deferred) {
 		if (mat != NULL && GPU_material_status(mat) == GPU_MAT_QUEUED) {
 			/* XXX Hack : we return NULL so that the engine will call DRW_shader_create_from_XXX
 			 * with the shader code and we will resume the compilation from there. */
@@ -336,7 +336,7 @@ GPUMaterial *DRW_shader_find_from_material(Material *ma, const void *engine_type
 
 GPUMaterial *DRW_shader_create_from_world(
         struct Scene *scene, World *wo, const void *engine_type, int options,
-        const char *vert, const char *geom, const char *frag_lib, const char *defines)
+        const char *vert, const char *geom, const char *frag_lib, const char *defines, bool deferred)
 {
 	GPUMaterial *mat = NULL;
 	if (DRW_state_is_image_render()) {
@@ -350,7 +350,7 @@ GPUMaterial *DRW_shader_create_from_world(
 	}
 
 	if (GPU_material_status(mat) == GPU_MAT_QUEUED) {
-		drw_deferred_shader_add(mat);
+		drw_deferred_shader_add(mat, deferred);
 	}
 
 	return mat;
@@ -358,7 +358,7 @@ GPUMaterial *DRW_shader_create_from_world(
 
 GPUMaterial *DRW_shader_create_from_material(
         struct Scene *scene, Material *ma, const void *engine_type, int options,
-        const char *vert, const char *geom, const char *frag_lib, const char *defines)
+        const char *vert, const char *geom, const char *frag_lib, const char *defines, bool deferred)
 {
 	GPUMaterial *mat = NULL;
 	if (DRW_state_is_image_render()) {
@@ -372,7 +372,7 @@ GPUMaterial *DRW_shader_create_from_material(
 	}
 
 	if (GPU_material_status(mat) == GPU_MAT_QUEUED) {
-		drw_deferred_shader_add(mat);
+		drw_deferred_shader_add(mat, deferred);
 	}
 
 	return mat;