From 3487236f9360df6c27d81452527c3b4d3703e8a8 Mon Sep 17 00:00:00 2001
From: Bill Kendrick <nbs@sonic.net>
Date: Wed, 8 Sep 2021 00:53:47 -0700
Subject: [PATCH] Animated brushes can rotate now

Takes advantage of SDL_gfxBlitRGBA(), also from SDL_gfx.
---
 docs/CHANGES.txt |  7 +++----
 src/tuxpaint.c   | 30 +++++++++++++++++++++++++++---
 2 files changed, 30 insertions(+), 7 deletions(-)

diff --git a/docs/CHANGES.txt b/docs/CHANGES.txt
index 82572e8af..d76d895ae 100644
--- a/docs/CHANGES.txt
+++ b/docs/CHANGES.txt
@@ -8,7 +8,7 @@ http://www.tuxpaint.org/
 
 $Id$
 
-2021.September.6 (0.9.27)
+2021.September.8 (0.9.27)
   * New Magic Tools:
     ----------------
     * "Opposite" -- Change parts of the picture to their complementary
@@ -33,17 +33,16 @@ $Id$
 
   * Other Improvements:
     -------------------
-    * WIP Rotational brushes now supported.  Unlike "directional"
+    * Rotational brushes now supported.  Unlike "directional"
       brushes, in which a 3x3 grid representing the 8 cardinal
       directions (45 degree steps) is used, only a single brush image
       is required, and Tux Paint will rotate it between 0 and 360 degrees,
       depending on the direction the mouse is going.  The brush's ".dat"
       file should contain a line consisting of the word "rotate".
-      * FIXME: WIP -- Doesn't handle animated brushes correctly!
       * Note: This adds a dependency on "SDL_gfx" library
         (Homepage: https://www.ferzkopp.net/wordpress/2016/01/02/sdl_gfx-sdl2_gfx/
         SourceForge project page: https://sourceforge.net/projects/sdlgfx/)
-        as this feature use it's "rotozoom" functionality.
+        as this feature use it's "rotozoomSurface()" and "SDL_gfxBlitRGBA()".
       (Closes https://sourceforge.net/p/tuxpaint/feature-requests/122/)
 
     * Replaced the "arrow_compass_points" brush with a single
diff --git a/src/tuxpaint.c b/src/tuxpaint.c
index e45977c7d..fc7b17d71 100644
--- a/src/tuxpaint.c
+++ b/src/tuxpaint.c
@@ -22,7 +22,7 @@
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   (See COPYING.txt)
 
-  June 14, 2002 - September 6, 2021
+  June 14, 2002 - September 8, 2021
 */
 
 #include "platform.h"
@@ -6045,8 +6045,32 @@ static void blit_brush(int x, int y, int direction, int rotation, int * w, int *
           SDL_Surface * rotated_brush;
 
           /* TODO: Cache these; discard them when the user changes the brush or alters its color */
-          /* FIXME: Account for src being within an animated brush! */
-          rotated_brush = rotozoomSurface(img_cur_brush, rotation, 1.0, SMOOTHING_ON);
+
+          rotated_brush = NULL;
+
+          if (img_cur_brush_frames != 1)
+            {
+              SDL_Surface * brush_frame_surf;
+
+              brush_frame_surf =
+                SDL_CreateRGBSurface(img_cur_brush->flags,
+                                     src.w,
+                                     src.h,
+                                     img_cur_brush->format->BitsPerPixel,
+                                     img_cur_brush->format->Rmask, img_cur_brush->format->Gmask, img_cur_brush->format->Bmask,
+                                     img_cur_brush->format->Amask);
+              if (brush_frame_surf != NULL)
+                {
+                  SDL_gfxBlitRGBA(img_cur_brush, &src, brush_frame_surf, NULL);
+                  rotated_brush = rotozoomSurface(brush_frame_surf, rotation, 1.0, SMOOTHING_ON);
+                  SDL_FreeSurface(brush_frame_surf);
+                }
+            }
+          else
+            {
+              rotated_brush = rotozoomSurface(img_cur_brush, rotation, 1.0, SMOOTHING_ON);
+            }
+
           if (rotated_brush != NULL)
             {
               src.x = 0;