Bugfix #26195

When rendering, during processing scene data, drawing in 3d window
is now locked. Can get extended to more areas in UI easily.

At least this solves all crashes with conflicting memory access in
render && 3d drawing. Deleting objects via operators or delete 
modifiers isn't locked yet.

Also fixed: crash on quitting a renderwindow when it was rendering.

source/blender/blenkernel/BKE_screen.h

@@ -112,7 +112,7 @@ typedef struct SpaceType {
 typedef struct ARegionType {
 	struct ARegionType *next, *prev;
 	
-	int			regionid;	/* unique identifier within this space */
+	int			regionid;	/* unique identifier within this space, defines RGN_TYPE_xxxx */
 	
 	/* add handlers, stuff you only do once or on area/region type/size changes */
 	void		(*init)(struct wmWindowManager *, struct ARegion *);
@@ -152,6 +152,8 @@ typedef struct ARegionType {
 	int			prefsizex, prefsizey;
 	/* default keymaps to add */
 	int			keymapflag;
+	/* return without drawing. lock is set by region definition, and copied to do_lock by render. can become flag */
+	short		do_lock, lock;
 } ARegionType;
 
 /* panel types */
@@ -231,6 +233,7 @@ void BKE_spacetypes_free(void);	/* only for quitting blender */
 /* spacedata */
 void BKE_spacedata_freelist(ListBase *lb);
 void BKE_spacedata_copylist(ListBase *lb1, ListBase *lb2);
+void BKE_spacedata_draw_locks(int set);
 
 /* area/regions */
 struct ARegion *BKE_area_region_copy(struct SpaceType *st, struct ARegion *ar);

source/blender/blenkernel/intern/screen.c

@@ -236,6 +236,26 @@ void BKE_spacedata_copylist(ListBase *lb1, ListBase *lb2)
 	}
 }
 
+/* facility to set locks for drawing to survive (render) threads accessing drawing data */
+/* lock can become bitflag too */
+/* should be replaced in future by better local data handling for threads */
+void BKE_spacedata_draw_locks(int set)
+{
+	SpaceType *st;
+	
+	for(st= spacetypes.first; st; st= st->next) {
+		ARegionType *art;
+	
+		for(art= st->regiontypes.first; art; art= art->next) {
+			if(set) 
+				art->do_lock= art->lock;
+			else 
+				art->do_lock= 0;
+		}
+	}
+}
+
+
 /* not region itself */
 void BKE_area_region_free(SpaceType *st, ARegion *ar)
 {
@@ -395,3 +415,4 @@ void BKE_screen_view3d_main_sync(ListBase *screen_lb, Scene *scene)
 					BKE_screen_view3d_sync((View3D*)sl, scene);
 	}
 }
+

source/blender/editors/render/render_internal.c

@@ -53,6 +53,7 @@
 #include "BKE_multires.h"
 #include "BKE_report.h"
 #include "BKE_sequencer.h"
+#include "BKE_screen.h"
 
 #include "WM_api.h"
 #include "WM_types.h"
@@ -636,6 +637,13 @@ static int render_breakjob(void *rjv)
 	return 0;
 }
 
+/* runs in thread, no cursor setting here works. careful with notifiers too (malloc conflicts) */
+/* maybe need a way to get job send notifer? */
+static void render_drawlock(void *UNUSED(rjv), int lock)
+{
+	BKE_spacedata_draw_locks(lock);
+}
+
 /* catch esc */
 static int screen_render_modal(bContext *C, wmOperator *UNUSED(op), wmEvent *event)
 {
@@ -769,6 +777,7 @@ static int screen_render_invoke(bContext *C, wmOperator *op, wmEvent *event)
 	/* setup new render */
 	re= RE_NewRender(scene->id.name);
 	RE_test_break_cb(re, rj, render_breakjob);
+	RE_draw_lock_cb(re, rj, render_drawlock);
 	RE_display_draw_cb(re, rj, image_rect_update);
 	RE_stats_draw_cb(re, rj, image_renderinfo_cb);
 	RE_progress_cb(re, rj, render_progress_update);

source/blender/editors/screen/area.c

@@ -314,6 +314,10 @@ void ED_region_do_draw(bContext *C, ARegion *ar)
 	ARegionType *at= ar->type;
 	rcti winrct;
 	
+	/* see BKE_spacedata_draw_locks() */
+	if(at->do_lock)
+		return;
+	
 	/* checks other overlapping regions */
 	region_scissor_winrct(ar, &winrct);
 	

source/blender/editors/space_view3d/space_view3d.c

@@ -1087,6 +1087,7 @@ void ED_spacetype_view3d(void)
 	art->duplicate= view3d_main_area_duplicate;
 	art->listener= view3d_main_area_listener;
 	art->cursor= view3d_main_area_cursor;
+	art->lock= 1;	/* can become flag, see BKE_spacedata_draw_locks */
 	BLI_addhead(&st->regiontypes, art);
 	
 	/* regions: listview/buttons */

source/blender/render/extern/include/RE_pipeline.h

@@ -239,6 +239,7 @@ void RE_display_clear_cb(struct Render *re, void *handle, void (*f)(void *handle
 void RE_display_draw_cb	(struct Render *re, void *handle, void (*f)(void *handle, RenderResult *rr, volatile struct rcti *rect));
 void RE_stats_draw_cb	(struct Render *re, void *handle, void (*f)(void *handle, RenderStats *rs));
 void RE_progress_cb	(struct Render *re, void *handle, void (*f)(void *handle, float));
+void RE_draw_lock_cb		(struct Render *re, void *handle, void (*f)(void *handle, int));
 void RE_test_break_cb	(struct Render *re, void *handle, int (*f)(void *handle));
 void RE_error_cb		(struct Render *re, void *handle, void (*f)(void *handle, const char *str));
 

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

@@ -246,6 +246,8 @@ struct Render
 	void (*progress)(void *handle, float i);
 	void *prh;
 	
+	void (*draw_lock)(void *handle, int i);
+	void *dlh;
 	int (*test_break)(void *handle);
 	void *tbh;
 	

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

@@ -46,18 +46,18 @@
 
 #include "MEM_guardedalloc.h"
 
-#include "BKE_utildefines.h"
+#include "BKE_animsys.h"	/* <------ should this be here?, needed for sequencer update */
 #include "BKE_global.h"
 #include "BKE_image.h"
 #include "BKE_main.h"
 #include "BKE_node.h"
 #include "BKE_object.h"
+#include "BKE_pointcache.h"
 #include "BKE_report.h"
 #include "BKE_scene.h"
-#include "BKE_writeavi.h"	/* <------ should be replaced once with generic movie module */
 #include "BKE_sequencer.h"
-#include "BKE_pointcache.h"
-#include "BKE_animsys.h"	/* <------ should this be here?, needed for sequencer update */
+#include "BKE_utildefines.h"
+#include "BKE_writeavi.h"	/* <------ should be replaced once with generic movie module */
 
 #include "BLI_math.h"
 #include "BLI_blenlib.h"
@@ -1404,6 +1404,12 @@ void RE_progress_cb(Render *re, void *handle, void (*f)(void *handle, float))
 	re->prh= handle;
 }
 
+void RE_draw_lock_cb(Render *re, void *handle, void (*f)(void *handle, int i))
+{
+	re->draw_lock= f;
+	re->tbh= handle;
+}
+
 void RE_test_break_cb(Render *re, void *handle, int (*f)(void *handle))
 {
 	re->test_break= f;
@@ -1790,12 +1796,20 @@ static void do_render_3d(Render *re)
 //	re->cfra= cfra;	/* <- unused! */
 	re->scene->r.subframe = re->mblur_offs + re->field_offs;
 	
+	/* lock drawing in UI during data phase */
+	if(re->draw_lock)
+		re->draw_lock(re->dlh, 1);
+	
 	/* make render verts/faces/halos/lamps */
 	if(render_scene_needs_vector(re))
 		RE_Database_FromScene_Vectors(re, re->main, re->scene, re->lay);
 	else
 	   RE_Database_FromScene(re, re->main, re->scene, re->lay, 1);
 	
+	/* clear UI drawing locks */
+	if(re->draw_lock)
+		re->draw_lock(re->dlh, 0);
+	
 	threaded_tile_processor(re);
 	
 	/* do left-over 3d post effects (flares) */

source/blender/windowmanager/intern/wm_window.c

@@ -238,6 +238,8 @@ wmWindow *wm_window_copy(bContext *C, wmWindow *winorig)
 /* this is event from ghost, or exit-blender op */
 void wm_window_close(bContext *C, wmWindowManager *wm, wmWindow *win)
 {
+	bScreen *screen= win->screen;
+	
 	BLI_remlink(&wm->windows, win);
 	
 	wm_draw_window_clear(win);
@@ -246,14 +248,14 @@ void wm_window_close(bContext *C, wmWindowManager *wm, wmWindow *win)
 	WM_event_remove_handlers(C, &win->modalhandlers);
 	ED_screen_exit(C, win, win->screen); 
 	
-	/* if temp screen, delete it */
-	if(win->screen->temp) {
-		Main *bmain= CTX_data_main(C);
-		free_libblock(&bmain->screen, win->screen);
-	}
-	
 	wm_window_free(C, wm, win);
 	
+	/* if temp screen, delete it after window free (it stops jobs that can access it) */
+	if(screen->temp) {
+		Main *bmain= CTX_data_main(C);
+		free_libblock(&bmain->screen, screen);
+	}
+	
 	/* check remaining windows */
 	if(wm->windows.first) {
 		for(win= wm->windows.first; win; win= win->next)