Fix part of #33132: render resoltuion refresh issues after persistent images

was added for cycles.

This fixes the case where the option is disabled. I moved the option now to
Blender itself and made it keep the engine around only when it's enabled. Also
fixes case where there could be issues when switching to another renderer.

6 files changed, 42 insertions, 5 deletions

diff --git a/source/blender/editors/render/render_update.c b/source/blender/editors/render/render_update.c
index 0a2ca379518..5155f1001ab 100644
--- a/source/blender/editors/render/render_update.c
+++ b/source/blender/editors/render/render_update.c
@@ -58,6 +58,7 @@
 #include "GPU_material.h"
 
 #include "RE_engine.h"
+#include "RE_pipeline.h"
 
 #include "ED_node.h"
 #include "ED_render.h"
@@ -157,6 +158,8 @@ void ED_render_engine_changed(Main *bmain)
 	for (sc = bmain->screen.first; sc; sc = sc->id.next)
 		for (sa = sc->areabase.first; sa; sa = sa->next)
 			ED_render_engine_area_exit(sa);
+
+	RE_FreePersistentData();
 }
 
 /***************************** Updates ***********************************
diff --git a/source/blender/makesdna/DNA_scene_types.h b/source/blender/makesdna/DNA_scene_types.h
index 1479d5268ed..251e6a7eb4e 100644
--- a/source/blender/makesdna/DNA_scene_types.h
+++ b/source/blender/makesdna/DNA_scene_types.h
@@ -1187,11 +1187,12 @@ typedef struct Scene {
 		/* Use the same flag for autothreads */
 #define R_FIXED_THREADS		0x80000 
 
-#define R_SPEED			0x100000
-#define R_SSS			0x200000
-#define R_NO_OVERWRITE	0x400000 /* skip existing files */
-#define R_TOUCH			0x800000 /* touch files before rendering */
-#define R_SIMPLIFY		0x1000000
+#define R_SPEED				0x100000
+#define R_SSS				0x200000
+#define R_NO_OVERWRITE		0x400000  /* skip existing files */
+#define R_TOUCH				0x800000  /* touch files before rendering */
+#define R_SIMPLIFY			0x1000000
+#define R_PERSISTENT_DATA	0x2000000 /* keep data around for re-render */
 
 /* seq_flag */
 #define R_SEQ_GL_PREV 1
diff --git a/source/blender/makesrna/intern/rna_scene.c b/source/blender/makesrna/intern/rna_scene.c
index b102d463195..5e4eb526b76 100644
--- a/source/blender/makesrna/intern/rna_scene.c
+++ b/source/blender/makesrna/intern/rna_scene.c
@@ -1254,6 +1254,12 @@ static void rna_Scene_simplify_update(Main *bmain, Scene *scene, PointerRNA *ptr
 		rna_Scene_use_simplify_update(bmain, scene, ptr);
 }
 
+static void rna_Scene_use_persistent_data_update(Main *bmain, Scene *scene, PointerRNA *UNUSED(ptr))
+{
+	if (!(scene->r.mode & R_PERSISTENT_DATA))
+		RE_FreePersistentData();
+}
+
 static int rna_Scene_use_audio_get(PointerRNA *ptr)
 {
 	Scene *scene = (Scene *)ptr->data;
@@ -4036,6 +4042,12 @@ static void rna_def_scene_render_data(BlenderRNA *brna)
 	RNA_def_property_boolean_sdna(prop, NULL, "simplify_flag", R_SIMPLE_NO_TRIANGULATE);
 	RNA_def_property_ui_text(prop, "Skip Quad to Triangles", "Disable non-planar quads being triangulated");
 
+	/* persistent data */
+	prop = RNA_def_property(srna, "use_persistent_data", PROP_BOOLEAN, PROP_NONE);
+	RNA_def_property_boolean_sdna(prop, NULL, "mode", R_PERSISTENT_DATA);
+	RNA_def_property_ui_text(prop, "Persistent Data", "Keep render data around for faster re-renders");
+	RNA_def_property_update(prop, 0, "rna_Scene_use_persistent_data_update");
+
 	/* Scene API */
 	RNA_api_scene_render(srna);
 }
diff --git a/source/blender/render/extern/include/RE_pipeline.h b/source/blender/render/extern/include/RE_pipeline.h
index 984b1a8e651..ecdd1774221 100644
--- a/source/blender/render/extern/include/RE_pipeline.h
+++ b/source/blender/render/extern/include/RE_pipeline.h
@@ -170,6 +170,8 @@ void RE_FreeRender (struct Render *re);
 void RE_FreeAllRender (void);
 /* only call on file load */
 void RE_FreeAllRenderResults(void);
+/* for external render engines that can keep persistent data */
+void RE_FreePersistentData(void);
 
 /* get results and statistics */
 void RE_FreeRenderResult(struct RenderResult *rr);
diff --git a/source/blender/render/intern/source/external_engine.c b/source/blender/render/intern/source/external_engine.c
index 736cb5de7c3..d771cf2253d 100644
--- a/source/blender/render/intern/source/external_engine.c
+++ b/source/blender/render/intern/source/external_engine.c
@@ -382,6 +382,11 @@ int RE_engine_render(Render *re, int do_all)
 	if (type->render)
 		type->render(engine, re->scene);
 
+	if(!(re->r.mode & R_PERSISTENT_DATA)) {
+		RE_engine_free(re->engine);
+		re->engine = NULL;
+	}
+
 	if (re->result->do_exr_tile) {
 		BLI_rw_mutex_lock(&re->resultmutex, THREAD_LOCK_WRITE);
 		render_result_exr_file_end(re);
diff --git a/source/blender/render/intern/source/pipeline.c b/source/blender/render/intern/source/pipeline.c
index 369818d37d5..3797430952c 100644
--- a/source/blender/render/intern/source/pipeline.c
+++ b/source/blender/render/intern/source/pipeline.c
@@ -244,6 +244,7 @@ Render *RE_GetRender(const char *name)
 	return re;
 }
 
+
 /* if you want to know exactly what has been done */
 RenderResult *RE_AcquireResultRead(Render *re)
 {
@@ -424,6 +425,19 @@ void RE_FreeAllRenderResults(void)
 	}
 }
 
+void RE_FreePersistentData()
+{
+	Render *re;
+
+	/* render engines can be kept around for quick re-render, this clears all */
+	for (re = RenderGlobal.renderlist.first; re; re = re->next) {
+		if (re->engine) {
+			RE_engine_free(re);
+			re->engine = NULL;
+		}
+	}
+}
+
 /* ********* initialize state ******** */