New canvas pigment (image map).

1 files changed, 58 insertions, 0 deletions

diff --git a/libdimension/canvas_pigment.c b/libdimension/canvas_pigment.c
new file mode 100644
index 0000000..b4c6823
--- /dev/null
+++ b/libdimension/canvas_pigment.c
@@ -0,0 +1,58 @@
+/*************************************************************************
+ * Copyright (C) 2010 Tavian Barnes <tavianator@gmail.com>               *
+ *                                                                       *
+ * This file is part of The Dimension Library.                           *
+ *                                                                       *
+ * The Dimension Library is free software; you can redistribute it and/  *
+ * or modify it under the terms of the GNU Lesser General Public License *
+ * as published by the Free Software Foundation; either version 3 of the *
+ * License, or (at your option) any later version.                       *
+ *                                                                       *
+ * The Dimension Library is distributed in the hope that it will be      *
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty   *
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU  *
+ * Lesser General Public License for more details.                       *
+ *                                                                       *
+ * You should have received a copy of the GNU Lesser General Public      *
+ * License along with this program.  If not, see                         *
+ * <http://www.gnu.org/licenses/>.                                       *
+ *************************************************************************/
+
+#include "dimension.h"
+
+/* Canvas color pigment callback */
+static dmnsn_color dmnsn_canvas_pigment_fn(const dmnsn_pigment *pigment,
+                                           dmnsn_vector v);
+static void dmnsn_canvas_pigment_free_fn(void *ptr);
+
+/* Create a canvas color */
+dmnsn_pigment *
+dmnsn_new_canvas_pigment(dmnsn_canvas *canvas)
+{
+  dmnsn_pigment *pigment = dmnsn_new_pigment();
+  pigment->pigment_fn = &dmnsn_canvas_pigment_fn;
+  pigment->free_fn    = &dmnsn_canvas_pigment_free_fn;
+  pigment->ptr        = canvas;
+  return pigment;
+}
+
+/* Canvas color callback */
+static dmnsn_color
+dmnsn_canvas_pigment_fn(const dmnsn_pigment *pigment, dmnsn_vector v)
+{
+  dmnsn_canvas *canvas = pigment->ptr;
+
+  int x = v.x*(canvas->x - 1) + 0.5;
+  int y = v.x*(canvas->x - 1) + 0.5;
+  if (x >= 0 && y >= 0 && x < canvas->x && y < canvas->y) {
+    return dmnsn_get_pixel(canvas, x, y);
+  } else {
+    return dmnsn_black;
+  }
+}
+
+static void
+dmnsn_canvas_pigment_free_fn(void *ptr)
+{
+  dmnsn_delete_canvas(ptr);
+}