10 files changed, 153 insertions, 104 deletions

diff --git a/source/blender/blenkernel/BKE_screen.h b/source/blender/blenkernel/BKE_screen.h
index 17cca92c1fc..36708cb11a4 100644
--- a/source/blender/blenkernel/BKE_screen.h
+++ b/source/blender/blenkernel/BKE_screen.h
@@ -140,8 +140,8 @@ typedef struct ARegionType {
 	void (*exit)(struct wmWindowManager *, struct ARegion *);
 	/* draw entirely, view changes should be handled here */
 	void (*draw)(const struct bContext *, struct ARegion *);
-	/* optional, refresh popup before drawing */
-	void (*refresh)(const struct bContext *, struct ARegion *);
+	/* optional, compute button layout before drawing for dynamic size */
+	void (*layout)(const struct bContext *, struct ARegion *);
 	/* snap the size of the region (can be NULL for no snapping). */
 	int (*snap_size)(const struct ARegion *ar, int size, int axis);
 	/* contextual changes should be handled here */
diff --git a/source/blender/editors/include/ED_screen.h b/source/blender/editors/include/ED_screen.h
index b5f1d947076..a1c429043cc 100644
--- a/source/blender/editors/include/ED_screen.h
+++ b/source/blender/editors/include/ED_screen.h
@@ -65,6 +65,7 @@ struct wmMsgSubscribeValue;
 void    ED_region_do_listen(
         struct bScreen *sc, struct ScrArea *sa, struct ARegion *ar,
         struct wmNotifier *note, const Scene *scene);
+void    ED_region_do_layout(struct bContext *C, struct ARegion *ar);
 void    ED_region_do_draw(struct bContext *C, struct ARegion *ar);
 void    ED_region_exit(struct bContext *C, struct ARegion *ar);
 void    ED_region_pixelspace(struct ARegion *ar);
@@ -81,6 +82,8 @@ void    ED_region_panels(
             const bool vertical);
 void    ED_region_header_init(struct ARegion *ar);
 void    ED_region_header(const struct bContext *C, struct ARegion *ar);
+void    ED_region_header_layout(const struct bContext *C, struct ARegion *ar);
+void    ED_region_header_draw(const struct bContext *C, struct ARegion *ar);
 void    ED_region_cursor_set(struct wmWindow *win, struct ScrArea *sa, struct ARegion *ar);
 void    ED_region_toggle_hidden(struct bContext *C, struct ARegion *ar);
 void    ED_region_visibility_change_update(struct bContext *C, struct ARegion *ar);
@@ -135,6 +138,7 @@ int     ED_area_headersize(void);
 int     ED_area_global_size_y(const ScrArea *area);
 bool    ED_area_is_global(const ScrArea *area);
 int     ED_region_global_size_y(void);
+void    ED_area_update_region_sizes(struct wmWindowManager *wm, struct wmWindow *win, struct ScrArea *area);
 
 ScrArea *ED_screen_areas_iter_first(const struct wmWindow *win, const bScreen *screen);
 ScrArea *ED_screen_areas_iter_next(const bScreen *screen, const ScrArea *area);
diff --git a/source/blender/editors/include/UI_interface.h b/source/blender/editors/include/UI_interface.h
index 7fd48ce081c..20c4552e6b2 100644
--- a/source/blender/editors/include/UI_interface.h
+++ b/source/blender/editors/include/UI_interface.h
@@ -475,6 +475,8 @@ uiBlock *UI_block_begin(const struct bContext *C, struct ARegion *region, const
 void UI_block_end_ex(const struct bContext *C, uiBlock *block, const int xy[2], int r_xy[2]);
 void UI_block_end(const struct bContext *C, uiBlock *block);
 void UI_block_draw(const struct bContext *C, struct uiBlock *block);
+void UI_blocklist_update_window_matrix(const struct bContext *C, const struct ListBase *lb);
+void UI_blocklist_draw(const struct bContext *C, const struct ListBase *lb);
 void UI_block_update_from_old(const struct bContext *C, struct uiBlock *block);
 
 uiBlock *UI_block_find_in_region(const char *name, struct ARegion *ar);
diff --git a/source/blender/editors/interface/interface.c b/source/blender/editors/interface/interface.c
index eb69ccef2e4..99387a47670 100644
--- a/source/blender/editors/interface/interface.c
+++ b/source/blender/editors/interface/interface.c
@@ -224,6 +224,26 @@ void ui_region_to_window(const ARegion *ar, int *x, int *y)
 	*y += ar->winrct.ymin;
 }
 
+static void ui_update_window_matrix(const wmWindow *window, const ARegion *region, uiBlock *block)
+{
+	/* window matrix and aspect */
+	if (region && region->visible) {
+		/* Get projection matrix which includes View2D translation and zoom. */
+		gpuGetProjectionMatrix(block->winmat);
+		block->aspect = 2.0f / fabsf(region->winx * block->winmat[0][0]);
+	}
+	else {
+		/* No subwindow created yet, for menus for example, so we use the main
+		 * window instead, since buttons are created there anyway. */
+		int width = WM_window_pixels_x(window);
+		int height = WM_window_pixels_y(window);
+		rcti winrct = {0, width - 1, 0, height - 1};
+
+		wmGetProjectionMatrix(block->winmat, &winrct);
+		block->aspect = 2.0f / fabsf(width * block->winmat[0][0]);
+	}
+}
+
 /**
  * Popups will add a margin to #ARegion.winrct for shadow,
  * for interactivity (point-inside tests for eg), we want the winrct without the margin added.
@@ -2670,6 +2690,27 @@ void UI_block_free(const bContext *C, uiBlock *block)
 	MEM_freeN(block);
 }
 
+void UI_blocklist_update_window_matrix(const bContext *C, const ListBase *lb)
+{
+	ARegion *region = CTX_wm_region(C);
+	wmWindow *window = CTX_wm_window(C);
+
+	for (uiBlock *block = lb->first; block; block = block->next) {
+		if (block->active) {
+			ui_update_window_matrix(window, region, block);
+		}
+	}
+}
+
+void UI_blocklist_draw(const bContext *C, const ListBase *lb)
+{
+	for (uiBlock *block = lb->first; block; block = block->next) {
+		if (block->active) {
+			UI_block_draw(C, block);
+		}
+	}
+}
+
 /* can be called with C==NULL */
 void UI_blocklist_free(const bContext *C, ListBase *lb)
 {
@@ -2755,25 +2796,13 @@ uiBlock *UI_block_begin(const bContext *C, ARegion *region, const char *name, sh
 	if (region)
 		UI_block_region_set(block, region);
 
-	/* window matrix and aspect */
-	if (region && region->visible) {
-		gpuGetProjectionMatrix(block->winmat);
+	/* Set window matrix and aspect for region and OpenGL state. */
+	ui_update_window_matrix(window, region, block);
 
-		block->aspect = 2.0f / fabsf(region->winx * block->winmat[0][0]);
-	}
-	else {
-		/* no subwindow created yet, for menus for example, so we
-		 * use the main window instead, since buttons are created
-		 * there anyway */
-		int width = WM_window_pixels_x(window);
-		int height = WM_window_pixels_y(window);
-		rcti winrct = {0, width -1, 0, height - 1};
-
-		wmGetProjectionMatrix(block->winmat, &winrct);
-
-		block->aspect = 2.0f / fabsf(width * block->winmat[0][0]);
+	/* Tag as popup menu if not created within a region. */
+	if (!(region && region->visible)) {
 		block->auto_open = true;
-		block->flag |= UI_BLOCK_LOOP; /* tag as menu */
+		block->flag |= UI_BLOCK_LOOP;
 	}
 
 	return block;
diff --git a/source/blender/editors/interface/interface_region_popup.c b/source/blender/editors/interface/interface_region_popup.c
index f397c62920b..4f8e9090a4a 100644
--- a/source/blender/editors/interface/interface_region_popup.c
+++ b/source/blender/editors/interface/interface_region_popup.c
@@ -682,7 +682,7 @@ uiPopupBlockHandle *ui_popup_block_create(
 
 	memset(&type, 0, sizeof(ARegionType));
 	type.draw = ui_block_region_draw;
-	type.refresh = ui_block_region_refresh;
+	type.layout = ui_block_region_refresh;
 	type.regionid = RGN_TYPE_TEMPORARY;
 	ar->type = &type;
 
diff --git a/source/blender/editors/screen/area.c b/source/blender/editors/screen/area.c
index 6e45b184478..5e68ad1218d 100644
--- a/source/blender/editors/screen/area.c
+++ b/source/blender/editors/screen/area.c
@@ -501,6 +501,27 @@ void ED_area_do_msg_notify_tag_refresh(
 }
 
 /* only exported for WM */
+void ED_region_do_layout(bContext *C, ARegion *ar)
+{
+	/* This is optional, only needed for dynamically sized regions. */
+	ScrArea *sa = CTX_wm_area(C);
+	ARegionType *at = ar->type;
+
+	if (!at->layout) {
+		return;
+	}
+
+	if (at->do_lock) {
+		return;
+	}
+
+	ar->do_draw |= RGN_DRAWING;
+
+	UI_SetTheme(sa ? sa->spacetype : 0, at->regionid);
+	at->layout(C, ar);
+}
+
+/* only exported for WM */
 void ED_region_do_draw(bContext *C, ARegion *ar)
 {
 	wmWindow *win = CTX_wm_window(C);
@@ -1187,9 +1208,8 @@ static void region_rect_recursive(wmWindow *win, ScrArea *sa, ARegion *ar, rcti
 	if (ar->next == NULL && alignment != RGN_ALIGN_QSPLIT)
 		alignment = RGN_ALIGN_NONE;
 
-	/* prefsize, for header we stick to exception (prevent dpi rounding error) */
-	const float sizex_dpi_fac = (ar->flag & RGN_SIZEX_DPI_APPLIED) ? 1.0f : UI_DPI_FAC;
-	prefsizex = sizex_dpi_fac * ((ar->sizex > 1) ? ar->sizex + 0.5f : ar->type->prefsizex);
+	/* prefsize, taking into account DPI */
+	prefsizex = UI_DPI_FAC * ((ar->sizex > 1) ? ar->sizex + 0.5f : ar->type->prefsizex);
 
 	if (ar->regiontype == RGN_TYPE_HEADER) {
 		prefsizey = ED_area_headersize();
@@ -1514,8 +1534,12 @@ static void ed_default_handlers(wmWindowManager *wm, ScrArea *sa, ListBase *hand
 	}
 }
 
-void screen_area_update_region_sizes(wmWindowManager *wm, wmWindow *win, ScrArea *area)
+void ED_area_update_region_sizes(wmWindowManager *wm, wmWindow *win, ScrArea *area)
 {
+	if (!(area->flag & AREA_FLAG_REGION_SIZE_UPDATE)) {
+		return;
+	}
+
 	const int size_x = WM_window_pixels_x(win);
 	const int size_y = WM_window_pixels_y(win);
 	rcti rect;
@@ -1898,6 +1922,23 @@ static ThemeColorID region_background_color_id(const bContext *C, const ARegion
 	}
 }
 
+static void region_clear_color(const bContext *C, const ARegion *ar, ThemeColorID colorid)
+{
+	if (ar->overlap) {
+		/* view should be in pixelspace */
+		UI_view2d_view_restore(C);
+
+		float back[4];
+		UI_GetThemeColor4fv(colorid, back);
+		glClearColor(back[3] * back[0], back[3] * back[1], back[3] * back[2], back[3]);
+		glClear(GL_COLOR_BUFFER_BIT);
+	}
+	else {
+		UI_ThemeClearColor(colorid);
+		glClear(GL_COLOR_BUFFER_BIT);
+	}
+}
+
 void ED_region_panels(const bContext *C, ARegion *ar, const char *context, int contextnr, const bool vertical)
 {
 	const WorkSpace *workspace = CTX_wm_workspace(C);
@@ -2124,20 +2165,7 @@ void ED_region_panels(const bContext *C, ARegion *ar, const char *context, int c
 		}
 	}
 
-	/* clear */
-	if (ar->overlap) {
-		/* view should be in pixelspace */
-		UI_view2d_view_restore(C);
-
-		float back[4];
-		UI_GetThemeColor4fv((ar->type->regionid == RGN_TYPE_PREVIEW) ? TH_PREVIEW_BACK : TH_BACK, back);
-		glClearColor(back[3] * back[0], back[3] * back[1], back[3] * back[2], back[3]);
-		glClear(GL_COLOR_BUFFER_BIT);
-	}
-	else {
-		UI_ThemeClearColor((ar->type->regionid == RGN_TYPE_PREVIEW) ? TH_PREVIEW_BACK : TH_BACK);
-		glClear(GL_COLOR_BUFFER_BIT);
-	}
+	region_clear_color(C, ar, (ar->type->regionid == RGN_TYPE_PREVIEW) ? TH_PREVIEW_BACK : TH_BACK);
 	
 	/* reset line width for drawing tabs */
 	glLineWidth(1.0f);
@@ -2171,7 +2199,7 @@ void ED_region_panels_init(wmWindowManager *wm, ARegion *ar)
 	WM_event_add_keymap_handler(&ar->handlers, keymap);
 }
 
-void ED_region_header(const bContext *C, ARegion *ar)
+void ED_region_header_layout(const bContext *C, ARegion *ar)
 {
 	uiStyle *style = UI_style_get_dpi();
 	uiBlock *block;
@@ -2183,10 +2211,6 @@ void ED_region_header(const bContext *C, ARegion *ar)
 	const int start_ofs = 0.4f * UI_UNIT_X;
 	bool region_layout_based = ar->flag & RGN_FLAG_DYNAMIC_SIZE;
 
-	/* clear */
-	UI_ThemeClearColor(region_background_color_id(C, ar));
-	glClear(GL_COLOR_BUFFER_BIT);
-	
 	/* set view2d view matrix for scrolling (without scrollers) */
 	UI_view2d_view_ortho(&ar->v2d);
 
@@ -2221,27 +2245,50 @@ void ED_region_header(const bContext *C, ARegion *ar)
 		if (xco > maxco)
 			maxco = xco;
 
-		if (region_layout_based && (ar->sizex != (maxco + start_ofs))) {
+		int new_sizex = (maxco + start_ofs) / UI_DPI_FAC;
+
+		if (region_layout_based && (ar->sizex != new_sizex)) {
 			/* region size is layout based and needs to be updated */
 			ScrArea *sa = CTX_wm_area(C);
 
-			ar->sizex = maxco + start_ofs;
-			UI_view2d_region_reinit(&ar->v2d, V2D_COMMONVIEW_HEADER, ar->sizex, ar->winy);
-
+			ar->sizex = new_sizex;
 			sa->flag |= AREA_FLAG_REGION_SIZE_UPDATE;
-			ar->flag |= RGN_SIZEX_DPI_APPLIED;
 		}
+
 		UI_block_end(C, block);
-		UI_block_draw(C, block);
 	}
 
 	/* always as last  */
 	UI_view2d_totRect_set(&ar->v2d, maxco + (region_layout_based ? 0 : UI_UNIT_X + 80), headery);
 
-	/* restore view matrix? */
+	/* restore view matrix */
+	UI_view2d_view_restore(C);
+}
+
+void ED_region_header_draw(const bContext *C, ARegion *ar)
+{
+	UI_view2d_view_ortho(&ar->v2d);
+
+	/* clear */
+	region_clear_color(C, ar, region_background_color_id(C, ar));
+
+	/* View2D matrix might have changed due to dynamic sized regions. */
+	UI_blocklist_update_window_matrix(C, &ar->uiblocks);
+
+	/* draw blocks */
+	UI_blocklist_draw(C, &ar->uiblocks);
+
+	/* restore view matrix */
 	UI_view2d_view_restore(C);
 }
 
+void ED_region_header(const bContext *C, ARegion *ar)
+{
+	/* TODO: remove? */
+	ED_region_header_layout(C, ar);
+	ED_region_header_draw(C, ar);
+}
+
 void ED_region_header_init(ARegion *ar)
 {
 	UI_view2d_region_reinit(&ar->v2d, V2D_COMMONVIEW_HEADER, ar->winx, ar->winy);
diff --git a/source/blender/editors/screen/screen_edit.c b/source/blender/editors/screen/screen_edit.c
index c7d1605cbbf..1cadefadd5c 100644
--- a/source/blender/editors/screen/screen_edit.c
+++ b/source/blender/editors/screen/screen_edit.c
@@ -835,36 +835,6 @@ void ED_screen_refresh(wmWindowManager *wm, wmWindow *win)
 	screen->context = ed_screen_context;
 }
 
-static bool screen_regions_need_size_refresh(
-        const wmWindow *win, const bScreen *screen)
-{
-	ED_screen_areas_iter(win, screen, area) {
-		if (area->flag & AREA_FLAG_REGION_SIZE_UPDATE) {
-			return true;
-		}
-	}
-
-	return false;
-}
-
-static void screen_refresh_region_sizes_only(
-        wmWindowManager *wm, wmWindow *win,
-        bScreen *screen)
-{
-	const int window_size_x = WM_window_pixels_x(win);
-	const int window_size_y = WM_window_pixels_y(win);
-	const int screen_size_x = WM_window_screen_pixels_x(win);
-	const int screen_size_y = WM_window_screen_pixels_y(win);
-
-	screen_vertices_scale(win, screen, window_size_x, window_size_y, screen_size_x, screen_size_y);
-
-	ED_screen_areas_iter(win, screen, area) {
-		screen_area_update_region_sizes(wm, win, area);
-		/* XXX hack to force drawing */
-		ED_area_tag_redraw(area);
-	}
-}
-
 /* file read, set all screens, ... */
 void ED_screens_initialize(wmWindowManager *wm)
 {
@@ -887,9 +857,6 @@ void ED_screen_ensure_updated(wmWindowManager *wm, wmWindow *win, bScreen *scree
 	if (screen->do_refresh) {
 		ED_screen_refresh(wm, win);
 	}
-	else if (screen_regions_need_size_refresh(win, screen)) {
-		screen_refresh_region_sizes_only(wm, win, screen);
-	}
 }
 
 
diff --git a/source/blender/editors/space_topbar/space_topbar.c b/source/blender/editors/space_topbar/space_topbar.c
index f2824b3bf70..fc76fd9c638 100644
--- a/source/blender/editors/space_topbar/space_topbar.c
+++ b/source/blender/editors/space_topbar/space_topbar.c
@@ -132,11 +132,6 @@ static void topbar_main_region_init(wmWindowManager *wm, ARegion *region)
 	WM_event_add_keymap_handler(&region->handlers, keymap);
 }
 
-static void topbar_main_region_draw(const bContext *C, ARegion *region)
-{
-	ED_region_header(C, region);
-}
-
 static void topbar_operatortypes(void)
 {
 
@@ -156,11 +151,6 @@ static void topbar_header_region_init(wmWindowManager *UNUSED(wm), ARegion *ar)
 	ED_region_header_init(ar);
 }
 
-static void topbar_header_region_draw(const bContext *C, ARegion *ar)
-{
-	ED_region_header(C, ar);
-}
-
 static void topbar_main_region_listener(bScreen *UNUSED(sc), ScrArea *UNUSED(sa), ARegion *ar,
                                         wmNotifier *wmn, const Scene *UNUSED(scene))
 {
@@ -263,7 +253,8 @@ void ED_spacetype_topbar(void)
 	art = MEM_callocN(sizeof(ARegionType), "spacetype topbar main region");
 	art->regionid = RGN_TYPE_WINDOW;
 	art->init = topbar_main_region_init;
-	art->draw = topbar_main_region_draw;
+	art->layout = ED_region_header_layout;
+	art->draw = ED_region_header_draw;
 	art->listener = topbar_main_region_listener;
 	art->prefsizex = UI_UNIT_X * 5; /* Mainly to avoid glitches */
 	art->keymapflag = ED_KEYMAP_UI | ED_KEYMAP_VIEW2D | ED_KEYMAP_HEADER;
@@ -279,7 +270,8 @@ void ED_spacetype_topbar(void)
 	art->listener = topbar_header_listener;
 	art->message_subscribe = topbar_header_region_message_subscribe;
 	art->init = topbar_header_region_init;
-	art->draw = topbar_header_region_draw;
+	art->layout = ED_region_header_layout;
+	art->draw = ED_region_header_draw;
 
 	BLI_addhead(&st->regiontypes, art);
 
diff --git a/source/blender/makesdna/DNA_screen_types.h b/source/blender/makesdna/DNA_screen_types.h
index 18986206b23..4274f348b2d 100644
--- a/source/blender/makesdna/DNA_screen_types.h
+++ b/source/blender/makesdna/DNA_screen_types.h
@@ -464,11 +464,6 @@ enum {
 	 * just big enough to show all its content (if enough space is available).
 	 * Note that only ED_region_header supports this right now. */
 	RGN_FLAG_DYNAMIC_SIZE     = (1 << 2),
-	/* The region width stored in ARegion.sizex already has the DPI
-	 * factor applied, skip applying it again (in region_rect_recursive).
-	 * XXX Not nice at all. Leaving for now as temporary solution, but
-	 * it might cause issues if we change how ARegion.sizex is used... */
-	RGN_SIZEX_DPI_APPLIED       = (1 << 3),
 };
 
 /* region do_draw */
diff --git a/source/blender/windowmanager/intern/wm_draw.c b/source/blender/windowmanager/intern/wm_draw.c
index f111bc3e2d1..685e6f7e216 100644
--- a/source/blender/windowmanager/intern/wm_draw.c
+++ b/source/blender/windowmanager/intern/wm_draw.c
@@ -489,12 +489,25 @@ GPUViewport *WM_draw_region_get_bound_viewport(ARegion *ar)
 
 static void wm_draw_window_offscreen(bContext *C, wmWindow *win, bool stereo)
 {
+	wmWindowManager *wm = CTX_wm_manager(C);
 	bScreen *screen = WM_window_get_active_screen(win);
 
 	/* Draw screen areas into own frame buffer. */
 	ED_screen_areas_iter(win, screen, sa) {
 		CTX_wm_area_set(C, sa);
 
+		/* Compute UI layouts for dynamically size regions. */
+		for (ARegion *ar = sa->regionbase.first; ar; ar = ar->next) {
+			if (ar->visible && ar->do_draw && ar->type && ar->type->layout) {
+				CTX_wm_region_set(C, ar);
+				ED_region_do_layout(C, ar);
+				CTX_wm_region_set(C, NULL);
+			}
+		}
+
+		ED_area_update_region_sizes(wm, win, sa);
+
+		/* Then do actual drawing of regions. */
 		for (ARegion *ar = sa->regionbase.first; ar; ar = ar->next) {
 			if (ar->visible && ar->do_draw) {
 				CTX_wm_region_set(C, ar);
@@ -539,11 +552,11 @@ static void wm_draw_window_offscreen(bContext *C, wmWindow *win, bool stereo)
 		if (ar->visible) {
 			CTX_wm_menu_set(C, ar);
 
-			if (ar->type && ar->type->refresh) {
-				/* UI code reads the OpenGL state, but we have to
-				 * refresh beforehand in case the menu size changes. */
+			if (ar->type && ar->type->layout) {
+				/* UI code reads the OpenGL state, but we have to refesh
+				 * the UI layout beforehand in case the menu size changes. */
 				wmViewport(&ar->winrct);
-				ar->type->refresh(C, ar);
+				ar->type->layout(C, ar);
 			}
 
 			wm_draw_region_buffer_create(ar, false, false);