[gimp] app: convert aspect ratio to scale_x&scale_y just before matrix transform

[Alexia Death <alexiade src gnome org>]

commit 0cb1ada8183583c5742f0616c77cfad9becf1880
Author: Alexia Death <alexiadeath gmail com>
Date:   Mon May 10 00:11:07 2010 +0300

    app: convert aspect ratio to scale_x&scale_y just before matrix transform

 app/core/gimpbrush-transform.c |   48 ++++++++++++++++++++-------------------
 app/core/gimpbrush-transform.h |    4 +-
 app/paint/gimpbrushcore.c      |    3 +-
 3 files changed, 29 insertions(+), 26 deletions(-)
---
diff --git a/app/core/gimpbrush-transform.c b/app/core/gimpbrush-transform.c
index 16a1726..ca83acf 100644
--- a/app/core/gimpbrush-transform.c
+++ b/app/core/gimpbrush-transform.c
@@ -63,12 +63,8 @@ gimp_brush_real_transform_size (GimpBrush *brush,
   GimpMatrix3 matrix;
   gint        x, y;
 
-  if (aspect_ratio < 1.0)
-    gimp_brush_transform_matrix (brush->mask->width, brush->mask->height,
-                                 scale * aspect_ratio, scale, angle, &matrix);
-  else
-    gimp_brush_transform_matrix (brush->mask->width, brush->mask->height,
-                                 scale, scale / aspect_ratio, angle, &matrix);
+  gimp_brush_transform_matrix (brush->mask->width, brush->mask->height,
+                               scale, aspect_ratio, angle, &matrix);
 
   gimp_brush_transform_bounding_box (brush->mask, &matrix, &x, &y, width, height);
 }
@@ -173,12 +169,8 @@ gimp_brush_real_transform_mask (GimpBrush *brush,
 
   source = temp_buf_copy (brush->mask, NULL);
 
-   if (aspect_ratio < 1.0)
-    gimp_brush_transform_matrix (source->height, source->width,
-                                 scale * aspect_ratio, scale, angle, &matrix);
-  else
-    gimp_brush_transform_matrix (source->height, source->width,
-                                 scale, scale / aspect_ratio, angle, &matrix);
+  gimp_brush_transform_matrix (source->height, source->width,
+                               scale, aspect_ratio, angle, &matrix);
 
   if (gimp_matrix3_is_identity (&matrix))
     return temp_buf_copy (source, NULL);
@@ -460,12 +452,8 @@ gimp_brush_real_transform_pixmap (GimpBrush *brush,
 
   source = brush->pixmap;
 
-  if (aspect_ratio < 1.0)
-    gimp_brush_transform_matrix (source->height, source->width,
-                                 scale * aspect_ratio, scale, angle, &matrix);
-  else
-    gimp_brush_transform_matrix (source->height, source->width,
-                                 scale, scale / aspect_ratio, angle, &matrix);
+  gimp_brush_transform_matrix (source->height, source->width,
+                               scale, aspect_ratio, angle, &matrix);
 
   if (gimp_matrix3_is_identity (&matrix))
     return temp_buf_copy (source, NULL);
@@ -653,19 +641,33 @@ gimp_brush_real_transform_pixmap (GimpBrush *brush,
 void
 gimp_brush_transform_matrix (gdouble      width,
                              gdouble      height,
-                             gdouble      scale_x,
-                             gdouble      scale_y,
+                             gdouble      scale,
+                             gdouble      aspect_ratio,
                              gdouble      angle,
                              GimpMatrix3 *matrix)
 {
   const gdouble center_x = width  / 2;
   const gdouble center_y = height / 2;
+  gdouble scale_x;
+  gdouble scale_y;
+
+  if (aspect_ratio < 1.0)
+    {
+        scale_x = scale * aspect_ratio;
+        scale_y = scale;
+    }
+  else
+    {
+      scale_x = scale;
+      scale_y = scale / aspect_ratio;
+    }
 
   gimp_matrix3_identity (matrix);
-  gimp_matrix3_translate (matrix, - center_x, - center_y);
-  gimp_matrix3_rotate (matrix, -2 * G_PI * angle);
-  gimp_matrix3_translate (matrix, center_x, center_y);
   gimp_matrix3_scale (matrix, scale_x, scale_y);
+  gimp_matrix3_translate (matrix, - center_x * scale_x, - center_y * scale_y);
+  gimp_matrix3_rotate (matrix, -2 * G_PI * angle);
+  gimp_matrix3_translate (matrix, center_x * scale_x, center_y * scale_y);
+
 }
 
 /*  private functions  */
diff --git a/app/core/gimpbrush-transform.h b/app/core/gimpbrush-transform.h
index 7b3af61..5a587c2 100644
--- a/app/core/gimpbrush-transform.h
+++ b/app/core/gimpbrush-transform.h
@@ -42,8 +42,8 @@ TempBuf * gimp_brush_real_transform_pixmap (GimpBrush *brush,
 
 void        gimp_brush_transform_matrix    (gdouble            width,
                                             gdouble            height,
-                                            gdouble            scale_x,
-                                            gdouble            scale_y,
+                                            gdouble            scale,
+                                            gdouble            aspect_ratio,
                                             gdouble            angle,
                                             GimpMatrix3       *matrix);
 
diff --git a/app/paint/gimpbrushcore.c b/app/paint/gimpbrushcore.c
index 8cbb871..25273ad 100644
--- a/app/paint/gimpbrushcore.c
+++ b/app/paint/gimpbrushcore.c
@@ -1049,13 +1049,14 @@ gimp_brush_core_transform_bound_segs (GimpBrushCore    *core,
 
 
       gimp_brush_transform_matrix (height, width,
-                                   scale_x, scale_y, angle, &matrix);
+                                   scale, aspect_ratio, angle, &matrix);
 
       core->transformed_brush_bound_segs
                       = boundary_transform (core->brush_bound_segs,
                                             &core->n_brush_bound_segs,
                                             &matrix);
 
+      //FIXME. Do noy use scale_x/scale_y
       core->transformed_brush_bound_width = core->brush_bound_width * scale_x;
       core->transformed_brush_bound_height = core->brush_bound_height * scale_y;
     }