[cairo] [PATCH] Manually transpose the matrix in _cairo_gl_shader_bind_matrix()

Zan Dobersek zan at falconsigh.net
Fri May 8 01:50:25 PDT 2015


From: Zan Dobersek <zdobersek at igalia.com>

To maintain compatibility with OpenGL ES 2.0, the matrix in
_cairo_gl_shader_bind_matrix() should be manually transposed,
and GL_FALSE passed as the transpose argument to the
glUniformMatrix3fv() call as it is the only valid value for
that parameter in OpenGL ES 2.0.
---
 src/cairo-gl-shaders.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/cairo-gl-shaders.c b/src/cairo-gl-shaders.c
index 2710606..fe975d2 100644
--- a/src/cairo-gl-shaders.c
+++ b/src/cairo-gl-shaders.c
@@ -973,12 +973,12 @@ _cairo_gl_shader_bind_matrix (cairo_gl_context_t *ctx,
 {
     cairo_gl_dispatch_t *dispatch = &ctx->dispatch;
     float gl_m[9] = {
-	m->xx, m->xy, m->x0,
-	m->yx, m->yy, m->y0,
-	0,     0,     1
+	m->xx, m->yx, 0,
+	m->xy, m->yy, 0,
+	m->x0, m->y0, 1
     };
     assert (location != -1);
-    dispatch->UniformMatrix3fv (location, 1, GL_TRUE, gl_m);
+    dispatch->UniformMatrix3fv (location, 1, GL_FALSE, gl_m);
 }
 
 void
-- 
2.1.4



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