Fix sequencer border-flickering

Offscreen viewport drawing wasn't properly restoring the theme.
Add API calls to store/restore the theme so it can be temporarily overridden.

4 files changed, 34 insertions, 8 deletions

diff --git a/source/blender/editors/include/UI_resources.h b/source/blender/editors/include/UI_resources.h
index e6db938a1b0..d289e90c257 100644
--- a/source/blender/editors/include/UI_resources.h
+++ b/source/blender/editors/include/UI_resources.h
@@ -301,6 +301,11 @@ enum {
 struct bTheme;
 struct PointerRNA;
 
+struct bThemeState {
+	struct bTheme *theme;
+	int spacetype, regionid;
+};
+
 // THE CODERS API FOR THEMES:
 
 // sets the color
@@ -360,6 +365,9 @@ void    UI_SetTheme(int spacetype, int regionid);
 // get current theme
 struct bTheme *UI_GetTheme(void);
 
+void UI_Theme_Store(struct bThemeState *theme_state);
+void UI_Theme_Restore(struct bThemeState *theme_state);
+
 // return shadow width outside menus and popups */
 int UI_ThemeMenuShadowWidth(void);
 
diff --git a/source/blender/editors/interface/resources.c b/source/blender/editors/interface/resources.c
index 941ef08b8e1..aa5b2570952 100644
--- a/source/blender/editors/interface/resources.c
+++ b/source/blender/editors/interface/resources.c
@@ -61,9 +61,16 @@
 /* global for themes */
 typedef void (*VectorDrawFunc)(int x, int y, int w, int h, float alpha);
 
-static bTheme *theme_active = NULL;
-static int theme_spacetype = SPACE_VIEW3D;
-static int theme_regionid = RGN_TYPE_WINDOW;
+/* be sure to keep 'bThemeState' in sync */
+static struct bThemeState g_theme_state = {
+    NULL,
+    SPACE_VIEW3D,
+    RGN_TYPE_WINDOW,
+};
+
+#define theme_active g_theme_state.theme
+#define theme_spacetype g_theme_state.spacetype
+#define theme_regionid g_theme_state.regionid
 
 void ui_resources_init(void)
 {
@@ -1215,6 +1222,18 @@ bTheme *UI_GetTheme(void)
 	return U.themes.first;
 }
 
+/**
+ * for the rare case we need to temp swap in a different theme (offscreen render)
+ */
+void UI_Theme_Store(struct bThemeState *theme_state)
+{
+	*theme_state = g_theme_state;
+}
+void UI_Theme_Restore(struct bThemeState *theme_state)
+{
+	g_theme_state = *theme_state;
+}
+
 /* for space windows only */
 void UI_ThemeColor(int colorid)
 {
diff --git a/source/blender/editors/space_sequencer/sequencer_draw.c b/source/blender/editors/space_sequencer/sequencer_draw.c
index e4d9c986603..293a68c33b8 100644
--- a/source/blender/editors/space_sequencer/sequencer_draw.c
+++ b/source/blender/editors/space_sequencer/sequencer_draw.c
@@ -1529,7 +1529,6 @@ void draw_timeline_seq(const bContext *C, ARegion *ar)
 
 	if (sseq->draw_flag & SEQ_DRAW_BACKDROP) {
 		draw_image_seq(C, scene, ar, sseq, scene->r.cfra, 0, false, true);
-		UI_SetTheme(SPACE_SEQ, RGN_TYPE_WINDOW);
 		UI_view2d_view_ortho(v2d);
 	}
 		
diff --git a/source/blender/editors/space_view3d/view3d_draw.c b/source/blender/editors/space_view3d/view3d_draw.c
index 44c046098e2..65721d52dff 100644
--- a/source/blender/editors/space_view3d/view3d_draw.c
+++ b/source/blender/editors/space_view3d/view3d_draw.c
@@ -3012,6 +3012,7 @@ void ED_view3d_draw_offscreen(Scene *scene, View3D *v3d, ARegion *ar, int winx,
                               float viewmat[4][4], float winmat[4][4],
                               bool do_bgpic, bool do_sky)
 {
+	struct bThemeState theme_state;
 	int bwinx, bwiny;
 	rcti brect;
 
@@ -3029,7 +3030,7 @@ void ED_view3d_draw_offscreen(Scene *scene, View3D *v3d, ARegion *ar, int winx,
 	ar->winrct.xmax = winx;
 	ar->winrct.ymax = winy;
 
-	/* set theme */
+	UI_Theme_Store(&theme_state);
 	UI_SetTheme(SPACE_VIEW3D, RGN_TYPE_WINDOW);
 
 	/* set flags */
@@ -3076,8 +3077,7 @@ void ED_view3d_draw_offscreen(Scene *scene, View3D *v3d, ARegion *ar, int winx,
 
 	glPopMatrix();
 
-	/* XXX, without this the sequencer flickers with opengl draw enabled, need to find out why - campbell */
-	glColor4ub(255, 255, 255, 255);
+	UI_Theme_Restore(&theme_state);
 
 	G.f &= ~G_RENDER_OGL;
 }
@@ -3148,7 +3148,7 @@ ImBuf *ED_view3d_draw_offscreen_imbuf(Scene *scene, View3D *v3d, ARegion *ar, in
 	
 	if (ibuf->rect_float && ibuf->rect)
 		IMB_rect_from_float(ibuf);
-	
+
 	return ibuf;
 }