Support pad/crop from bottom, not just from the top.

[movit] / padding_effect.h

diff --git a/padding_effect.h b/padding_effect.h
index 3bd4aacb321a54c80ce98e23526d941a9f1bce58..fdefbe0fe1a7b0fe329ed094bacaf3065b113697 100644 (file)
--- a/padding_effect.h
+++ b/padding_effect.h
@@ -11,6 +11,10 @@
 // The border color is taken to be in linear gamma, sRGB, with premultiplied alpha.
 // You may not change it after calling finalize(), since that could change the
 // graph (need_linear_light() etc. depend on the border color you choose).
+//
+// As a convenience, if the flag “pad_from_bottom” is nonzero, the “top” parameter
+// will mean pixels from the bottom (matching OpenGL's usual bottom-left convention),
+// instead of from the top as usual.
 
 #include <GL/glew.h>
 #include <string>
@@ -39,6 +43,7 @@ private:
        int input_width, input_height;
        int output_width, output_height;
        float top, left;
+       int pad_from_bottom;
 };
 
 }  // namespace movit