Add render result caching.

Simply add an option to render settings to save an EXR cache,
just when the render is finished. Also changed RE_ReadRenderResult() to read
cache instead of temp sample files (those are fully volatile now anyway).

Path to save cached render results is an UserPreferences setting.

Also added 'Reload render' feature to the Image Editor (so one can now re-open a blend,
and in an Image Editor hit ctrl-R to (try to) reload last render from cache).

Reviewers: campbellbarton, sergey

Differential Revision: https://developer.blender.org/D553

release/scripts/startup/bl_ui/properties_render.py

@@ -396,7 +396,9 @@ class RENDER_PT_output(RenderButtonsPanel, Panel):
         col.prop(rd, "use_overwrite")
         col.prop(rd, "use_placeholder")
 
-        split.prop(rd, "use_file_extension")
+        col = split.column()
+        col.prop(rd, "use_file_extension")
+        col.prop(rd, "use_render_cache")
 
         layout.template_image_settings(image_settings, color_management=False)
 

release/scripts/startup/bl_ui/space_image.py

@@ -154,6 +154,8 @@ class IMAGE_MT_image(Menu):
 
         show_render = sima.show_render
 
+        layout.operator("image.read_renderlayers")
+
         if ima:
             if not show_render:
                 layout.operator("image.replace")

release/scripts/startup/bl_ui/space_userpref.py

@@ -865,6 +865,7 @@ class USERPREF_PT_file(Panel):
         sub.label(text="Scripts:")
         sub.label(text="Sounds:")
         sub.label(text="Temp:")
+        sub.label(text="Render Cache:")
         sub.label(text="I18n Branches:")
         sub.label(text="Image Editor:")
         sub.label(text="Animation Player:")
@@ -876,6 +877,7 @@ class USERPREF_PT_file(Panel):
         sub.prop(paths, "script_directory", text="")
         sub.prop(paths, "sound_directory", text="")
         sub.prop(paths, "temporary_directory", text="")
+        sub.prop(paths, "render_cache_directory", text="")
         sub.prop(paths, "i18n_branches_directory", text="")
         sub.prop(paths, "image_editor", text="")
         subsplit = sub.split(percentage=0.3)

source/blender/editors/space_image/image_intern.h

@@ -90,6 +90,8 @@ void IMAGE_OT_curves_point_set(struct wmOperatorType *ot);
 
 void IMAGE_OT_change_frame(struct wmOperatorType *ot);
 
+void IMAGE_OT_read_renderlayers(struct wmOperatorType *ot);
+
 /* image_panels.c */
 struct ImageUser *ntree_get_active_iuser(struct bNodeTree *ntree);
 void image_buttons_register(struct ARegionType *art);

source/blender/editors/space_image/image_ops.c

@@ -2997,3 +2997,35 @@ void IMAGE_OT_change_frame(wmOperatorType *ot)
 	/* rna */
 	RNA_def_int(ot->srna, "frame", 0, MINAFRAME, MAXFRAME, "Frame", "", MINAFRAME, MAXFRAME);
 }
+
+/* Reload cached render results... */
+/* goes over all scenes, reads render layers */
+static int image_read_renderlayers_exec(bContext *C, wmOperator *UNUSED(op))
+{
+	Scene *scene = CTX_data_scene(C);
+	SpaceImage *sima = CTX_wm_space_image(C);
+	Image *ima;
+
+	ima = BKE_image_verify_viewer(IMA_TYPE_R_RESULT, "Render Result");
+	if (sima->image == NULL) {
+		ED_space_image_set(sima, scene, NULL, ima);
+	}
+
+	RE_ReadRenderResult(scene, scene);
+
+	WM_event_add_notifier(C, NC_IMAGE | NA_EDITED, ima);
+	return OPERATOR_FINISHED;
+}
+
+void IMAGE_OT_read_renderlayers(wmOperatorType *ot)
+{
+	ot->name = "Read Render Layers";
+	ot->idname = "IMAGE_OT_read_renderlayers";
+	ot->description = "Read all the current scene's render layers from cache, as needed";
+
+	ot->poll = space_image_main_area_poll;
+	ot->exec = image_read_renderlayers_exec;
+
+	/* flags */
+	ot->flag = 0;
+}

source/blender/editors/space_image/space_image.c

@@ -255,6 +255,8 @@ static void image_operatortypes(void)
 	WM_operatortype_append(IMAGE_OT_toolshelf);
 
 	WM_operatortype_append(IMAGE_OT_change_frame);
+
+	WM_operatortype_append(IMAGE_OT_read_renderlayers);
 }
 
 static void image_keymap(struct wmKeyConfig *keyconf)
@@ -266,6 +268,7 @@ static void image_keymap(struct wmKeyConfig *keyconf)
 	WM_keymap_add_item(keymap, "IMAGE_OT_new", NKEY, KM_PRESS, KM_ALT, 0);
 	WM_keymap_add_item(keymap, "IMAGE_OT_open", OKEY, KM_PRESS, KM_ALT, 0);
 	WM_keymap_add_item(keymap, "IMAGE_OT_reload", RKEY, KM_PRESS, KM_ALT, 0);
+	WM_keymap_add_item(keymap, "IMAGE_OT_read_renderlayers", RKEY, KM_PRESS, KM_CTRL, 0);
 	WM_keymap_add_item(keymap, "IMAGE_OT_save", SKEY, KM_PRESS, KM_ALT, 0);
 	WM_keymap_add_item(keymap, "IMAGE_OT_save_as", F3KEY, KM_PRESS, 0, 0);
 	WM_keymap_add_item(keymap, "IMAGE_OT_properties", NKEY, KM_PRESS, 0, 0);

source/blender/makesdna/DNA_scene_types.h

@@ -1377,6 +1377,7 @@ typedef struct Scene {
 /* #define R_RECURS_PROTECTION	0x20000 */
 #define R_TEXNODE_PREVIEW	0x40000
 #define R_VIEWPORT_PREVIEW	0x80000
+#define R_EXR_CACHE_FILE	0x100000
 
 /* r->stamp */
 #define R_STAMP_TIME 	0x0001

source/blender/makesdna/DNA_userdef_types.h

@@ -422,6 +422,8 @@ typedef struct UserDef {
 	char tempdir[768];	/* FILE_MAXDIR length */
 	char fontdir[768];
 	char renderdir[1024]; /* FILE_MAX length */
+	/* EXR cache path */
+	char render_cachedir[768];  /* 768 = FILE_MAXDIR */
 	char textudir[768];
 	char pythondir[768];
 	char sounddir[768];

source/blender/makesrna/intern/rna_scene.c

@@ -4811,6 +4811,14 @@ static void rna_def_scene_render_data(BlenderRNA *brna)
 	                         "and length of frame numbers");
 	RNA_def_property_update(prop, NC_SCENE | ND_RENDER_OPTIONS, NULL);
 
+	/* Render result EXR cache. */
+	prop = RNA_def_property(srna, "use_render_cache", PROP_BOOLEAN, PROP_NONE);
+	RNA_def_property_boolean_sdna(prop, NULL, "scemode", R_EXR_CACHE_FILE);
+	RNA_def_property_ui_text(prop, "Cache Result",
+	                         "Save render cache to EXR files (useful for heavy compositing, "
+	                         "Note: affects indirectly rendered scenes)");
+	RNA_def_property_update(prop, NC_SCENE | ND_RENDER_OPTIONS, NULL);
+
 	/* Bake */
 	
 	prop = RNA_def_property(srna, "bake_type", PROP_ENUM, PROP_NONE);

source/blender/makesrna/intern/rna_userdef.c

@@ -4272,6 +4272,10 @@ static void rna_def_userdef_filepaths(BlenderRNA *brna)
 	RNA_def_property_ui_text(prop, "Temporary Directory", "The directory for storing temporary save files");
 	RNA_def_property_update(prop, 0, "rna_userdef_temp_update");
 
+	prop = RNA_def_property(srna, "render_cache_directory", PROP_STRING, PROP_DIRPATH);
+	RNA_def_property_string_sdna(prop, NULL, "render_cachedir");
+	RNA_def_property_ui_text(prop, "Render Cache Path", "Where to cache raw render results");
+
 	prop = RNA_def_property(srna, "image_editor", PROP_STRING, PROP_FILEPATH);
 	RNA_def_property_string_sdna(prop, NULL, "image_editor");
 	RNA_def_property_ui_text(prop, "Image Editor", "Path to an image editor");

source/blender/render/intern/include/render_result.h

@@ -81,9 +81,14 @@ void render_result_exr_file_end(struct Render *re);
 void render_result_exr_file_merge(struct RenderResult *rr, struct RenderResult *rrpart);
 
 void render_result_exr_file_path(struct Scene *scene, const char *layname, int sample, char *filepath);
-int render_result_exr_file_read(struct Render *re, int sample);
+int render_result_exr_file_read_sample(struct Render *re, int sample);
 int render_result_exr_file_read_path(struct RenderResult *rr, struct RenderLayer *rl_single, const char *filepath);
 
+/* EXR cache */
+
+void render_result_exr_file_cache_write(struct Render *re);
+bool render_result_exr_file_cache_read(struct Render *re);
+
 /* Combined Pixel Rect */
 
 struct ImBuf *render_result_rect_to_ibuf(struct RenderResult *rr, struct RenderData *rd);

source/blender/render/intern/source/external_engine.c

@@ -664,6 +664,12 @@ int RE_engine_render(Render *re, int do_all)
 		BLI_rw_mutex_unlock(&re->resultmutex);
 	}
 
+	if (re->r.scemode & R_EXR_CACHE_FILE) {
+		BLI_rw_mutex_lock(&re->resultmutex, THREAD_LOCK_WRITE);
+		render_result_exr_file_cache_write(re);
+		BLI_rw_mutex_unlock(&re->resultmutex);
+	}
+
 	RE_parts_free(re);
 
 	if (BKE_reports_contain(re->reports, RPT_ERROR))

source/blender/render/intern/source/pipeline.c

@@ -1229,7 +1229,13 @@ static void threaded_tile_processor(Render *re)
 		render_result_exr_file_end(re);
 		BLI_rw_mutex_unlock(&re->resultmutex);
 	}
-	
+
+	if (re->r.scemode & R_EXR_CACHE_FILE) {
+		BLI_rw_mutex_lock(&re->resultmutex, THREAD_LOCK_WRITE);
+		render_result_exr_file_cache_write(re);
+		BLI_rw_mutex_unlock(&re->resultmutex);
+	}
+
 	/* unset threadsafety */
 	g_break = 0;
 	
@@ -1662,7 +1668,10 @@ static void render_scene(Render *re, Scene *sce, int cfra)
 	
 	/* initial setup */
 	RE_InitState(resc, re, &sce->r, NULL, winx, winy, &re->disprect);
-	
+
+	/* We still want to use 'rendercache' setting from org (main) scene... */
+	resc->r.scemode = (resc->r.scemode & ~R_EXR_CACHE_FILE) | (re->r.scemode & R_EXR_CACHE_FILE);
+
 	/* still unsure entity this... */
 	resc->main = re->main;
 	resc->scene = sce;
@@ -1967,7 +1976,7 @@ static void composite_freestyle_renders(Render *re, int sample)
 
 			/* may be NULL in case of empty render layer */
 			if (freestyle_render) {
-				render_result_exr_file_read(freestyle_render, sample);
+				render_result_exr_file_read_sample(freestyle_render, sample);
 				FRS_composite_result(re, srl, freestyle_render);
 				RE_FreeRenderResult(freestyle_render->result);
 				freestyle_render->result = NULL;
@@ -2041,7 +2050,7 @@ static void do_merge_fullsample(Render *re, bNodeTree *ntree)
 				if (re1 && (re1->r.scemode & R_FULL_SAMPLE)) {
 					if (sample) {
 						BLI_rw_mutex_lock(&re->resultmutex, THREAD_LOCK_WRITE);
-						render_result_exr_file_read(re1, sample);
+						render_result_exr_file_read_sample(re1, sample);
 #ifdef WITH_FREESTYLE
 						if (re1->r.mode & R_EDGE_FRS)
 							composite_freestyle_renders(re1, sample);
@@ -3108,7 +3117,7 @@ bool RE_ReadRenderResult(Scene *scene, Scene *scenode)
 	re->scene_color_manage = BKE_scene_check_color_management_enabled(scene);
 	
 	BLI_rw_mutex_lock(&re->resultmutex, THREAD_LOCK_WRITE);
-	success = render_result_exr_file_read(re, 0);
+	success = render_result_exr_file_cache_read(re);
 	BLI_rw_mutex_unlock(&re->resultmutex);
 
 	return success;

source/blender/render/intern/source/render_result.c

@@ -37,6 +37,7 @@
 
 #include "BLI_utildefines.h"
 #include "BLI_listbase.h"
+#include "BLI_md5.h"
 #include "BLI_path_util.h"
 #include "BLI_rect.h"
 #include "BLI_string.h"
@@ -1012,7 +1013,7 @@ void render_result_exr_file_end(Render *re)
 	render_result_free_list(&re->fullresult, re->result);
 	re->result = NULL;
 
-	render_result_exr_file_read(re, 0);
+	render_result_exr_file_read_sample(re, 0);
 }
 
 /* save part into exr file */
@@ -1038,25 +1039,23 @@ void render_result_exr_file_path(Scene *scene, const char *layname, int sample,
 	BLI_make_file_string("/", filepath, BLI_temp_dir_session(), name);
 }
 
-/* only for temp buffer files, makes exact copy of render result */
-int render_result_exr_file_read(Render *re, int sample)
+/* only for temp buffer, makes exact copy of render result */
+int render_result_exr_file_read_sample(Render *re, int sample)
 {
 	RenderLayer *rl;
-	char str[FILE_MAX];
+	char str[FILE_MAXFILE + MAX_ID_NAME + MAX_ID_NAME + 100] = "";
 	bool success = true;
 
 	RE_FreeRenderResult(re->result);
 	re->result = render_result_new(re, &re->disprect, 0, RR_USE_MEM, RR_ALL_LAYERS);
 
 	for (rl = re->result->layers.first; rl; rl = rl->next) {
-
 		render_result_exr_file_path(re->scene, rl->name, sample, str);
 		printf("read exr tmp file: %s\n", str);
 
 		if (!render_result_exr_file_read_path(re->result, rl, str)) {
 			printf("cannot read: %s\n", str);
 			success = false;
-
 		}
 	}
 
@@ -1115,6 +1114,65 @@ int render_result_exr_file_read_path(RenderResult *rr, RenderLayer *rl_single, c
 	return 1;
 }
 
+static void render_result_exr_file_cache_path(Scene *sce, const char *root, char *r_path)
+{
+	char filename_full[FILE_MAX + MAX_ID_NAME + 100], filename[FILE_MAXFILE], dirname[FILE_MAXDIR];
+	char path_digest[16] = {0};
+	char path_hexdigest[33];
+
+	/* If root is relative, use either current .blend file dir, or temp one if not saved. */
+	if (G.main->name[0]) {
+		BLI_split_dirfile(G.main->name, dirname, filename, sizeof(dirname), sizeof(filename));
+		BLI_replace_extension(filename, sizeof(filename), "");  /* strip '.blend' */
+		md5_buffer(G.main->name, strlen(G.main->name), path_digest);
+	}
+	else {
+		BLI_strncpy(dirname, BLI_temp_dir_base(), sizeof(dirname));
+		BLI_strncpy(filename, "UNSAVED", sizeof(filename));
+	}
+	md5_to_hexdigest(path_digest, path_hexdigest);
+
+	/* Default to *non-volatile* tmp dir. */
+	if (*root == '\0') {
+		root = BLI_temp_dir_base();
+	}
+
+	BLI_snprintf(filename_full, sizeof(filename_full), "cached_RR_%s_%s_%s.exr",
+	             filename, sce->id.name + 2, path_hexdigest);
+	BLI_make_file_string(dirname, r_path, root, filename_full);
+}
+
+void render_result_exr_file_cache_write(Render *re)
+{
+	RenderResult *rr = re->result;
+	char str[FILE_MAXFILE + FILE_MAXFILE + MAX_ID_NAME + 100];
+	char *root = U.render_cachedir;
+
+	render_result_exr_file_cache_path(re->scene, root, str);
+	printf("Caching exr file, %dx%d, %s\n", rr->rectx, rr->recty, str);
+	RE_WriteRenderResult(NULL, rr, str, 0);
+}
+
+/* For cache, makes exact copy of render result */
+bool render_result_exr_file_cache_read(Render *re)
+{
+	char str[FILE_MAXFILE + MAX_ID_NAME + MAX_ID_NAME + 100] = "";
+	char *root = U.render_cachedir;
+
+	RE_FreeRenderResult(re->result);
+	re->result = render_result_new(re, &re->disprect, 0, RR_USE_MEM, RR_ALL_LAYERS);
+
+	/* First try cache. */
+	render_result_exr_file_cache_path(re->scene, root, str);
+
+	printf("read exr cache file: %s\n", str);
+	if (!render_result_exr_file_read_path(re->result, NULL, str)) {
+		printf("cannot read: %s\n", str);
+		return false;
+	}
+	return true;
+}
+
 /*************************** Combined Pixel Rect *****************************/
 
 ImBuf *render_result_rect_to_ibuf(RenderResult *rr, RenderData *rd)