X-Git-Url: http://git.draconx.ca/gitweb/rrace.git/blobdiff_plain/568ff47f18d09158e4760ff793be9004e4d61a96..aebcc2d9a4090d8136f750463b1cfbb73916d717:/src/motif_ui.c

diff --git a/src/motif_ui.c b/src/motif_ui.c
index 726e24f..4559ff6 100644
--- a/src/motif_ui.c
+++ b/src/motif_ui.c
@@ -205,18 +205,6 @@ construct_menu(const struct ui_menuitem *root, Widget parent, unsigned i)
 	}
 }
 
-static void game_resize(Widget w, void *data, void *cb_data)
-{
-	if (XtIsRealized(w))
-		x11_redraw_game(data, -1);
-}
-
-static void goal_resize(Widget w, void *data, void *cb_data)
-{
-	if (XtIsRealized(w))
-		x11_redraw_goal(data, -1);
-}
-
 /* Figure out which tiles intersect a rectangle. */
 static uint_fast32_t
 expose_mask(int rect_x, int rect_y, int rect_w, int rect_h,
@@ -228,6 +216,57 @@ expose_mask(int rect_x, int rect_y, int rect_w, int rect_h,
 	     & board_left((rect_x + rect_w - 1) / tile_w);
 }
 
+/*
+ * Calculate which tiles need to be redrawn after resizing.  This is the
+ * tiles which (at the new size) are fully contained in the previous area.
+ *
+ * When shrinking, this is all tiles, but when enlarging, the generated
+ * expose events will trigger drawing of the new area.
+ */
+static uint_fast32_t resize_helper(Widget w, Dimension *oldsz, int gridsz)
+{
+	Dimension new_w, new_h, common_w, common_h;
+
+	if (!XtIsRealized(w))
+		return 0;
+
+	XtVaGetValues(w, XmNwidth, &new_w, XmNheight, &new_h, (char *)NULL);
+	common_w = MIN(new_w, oldsz[0]);
+	common_h = MIN(new_h, oldsz[1]);
+	oldsz[0] = new_w;
+	oldsz[1] = new_h;
+	new_w /= gridsz;
+	new_h /= gridsz;
+
+	/* Round down to multiple of tile dimensions */
+	common_w = common_w / new_w * new_w;
+	common_h = common_h / new_h * new_h;
+
+	if (new_w > 0 && new_h > 0)
+		return expose_mask(0, 0, common_w, common_h, new_w, new_h);
+	return 0;
+}
+
+static void game_resize(Widget w, void *data, void *cb_data)
+{
+	struct app_state *state = data;
+	uint_fast32_t mask;
+
+	mask = resize_helper(w, state->game_sz, 5);
+	if (mask)
+		x11_redraw_game(data, mask);
+}
+
+static void goal_resize(Widget w, void *data, void *cb_data)
+{
+	struct app_state *state = data;
+	uint_fast32_t mask;
+
+	mask = resize_helper(w, state->goal_sz, 3);
+	if (mask)
+		x11_redraw_goal(data, mask);
+}
+
 static void game_expose(Widget w, void *data, void *cb_data)
 {
 	XmDrawingAreaCallbackStruct *cbs = cb_data;
@@ -271,8 +310,16 @@ void ui_initialize(struct app_state *state, Widget shell)
 	XtVaSetValues(menubar, XmNmenuHelpWidget, help, (char *)NULL);
 
 	configure_mainwin(state, XtNameToWidget(shell, "*game"));
+
+	XtVaGetValues(state->game, XmNwidth, &state->game_sz[0],
+	                           XmNheight, &state->game_sz[1],
+	                           (char *)NULL);
 	XtAddCallback(state->game, XmNresizeCallback, game_resize, state);
 	XtAddCallback(state->game, XmNexposeCallback, game_expose, state);
+
+	XtVaGetValues(state->game, XmNwidth, &state->goal_sz[0],
+	                           XmNheight, &state->goal_sz[1],
+	                           (char *)NULL);
 	XtAddCallback(state->goal, XmNresizeCallback, goal_resize, state);
 	XtAddCallback(state->goal, XmNexposeCallback, goal_expose, state);
 }