From 38221080181229d520522a20bcb1663ca19f7aff Mon Sep 17 00:00:00 2001
From: Matthew Waters <matthew@centricular.com>
Date: Thu, 31 Mar 2016 19:25:32 +1100
Subject: [PATCH 2/3] glshader: add glBindFragDataLocation

There are some cases where it's needed for binding in/out variables in shaders.
e.g. glsl 150 (gl 3.2) doesn't support the 'layout (location = ?)' specifiers in
the shader source so we have to bind them ourselves.

Upstream-Status: Backport [1.9.1]
---
 gst-libs/gst/gl/glprototypes/shaders.h | 10 ++++++++++
 gst-libs/gst/gl/gstglshader.c          | 20 ++++++++++++++++++++
 gst-libs/gst/gl/gstglshader.h          |  1 +
 3 files changed, 31 insertions(+)

diff --git a/gst-libs/gst/gl/glprototypes/shaders.h b/gst-libs/gst/gl/glprototypes/shaders.h
index 817e479..6d828db 100644
--- a/gst-libs/gst/gl/glprototypes/shaders.h
+++ b/gst-libs/gst/gl/glprototypes/shaders.h
@@ -362,3 +362,13 @@ GST_GL_EXT_FUNCTION (void, UniformMatrix3x4fv,
 GST_GL_EXT_FUNCTION (void, UniformMatrix4x3fv,
                      (GLint location, GLsizei count, GLboolean transpose, const GLfloat *value))
 GST_GL_EXT_END ()
+
+GST_GL_EXT_BEGIN (bind_frag_data,
+                  GST_GL_API_OPENGL | GST_GL_API_OPENGL3,
+                  3, 0,
+                  255, 255,
+                  "\0",
+                  "\0")
+GST_GL_EXT_FUNCTION (void, BindFragDataLocation,
+                     (GLuint program, GLuint index, const GLchar * name))
+GST_GL_EXT_END ()
diff --git a/gst-libs/gst/gl/gstglshader.c b/gst-libs/gst/gl/gstglshader.c
index 9d96784..9f09236 100644
--- a/gst-libs/gst/gl/gstglshader.c
+++ b/gst-libs/gst/gl/gstglshader.c
@@ -1306,3 +1306,23 @@ gst_gl_shader_bind_attribute_location (GstGLShader * shader, GLuint index,
 
   gl->BindAttribLocation (priv->program_handle, index, name);
 }
+
+void
+gst_gl_shader_bind_frag_data_location (GstGLShader * shader,
+    guint index, const gchar * name)
+{
+  GstGLShaderPrivate *priv;
+  GstGLFuncs *gl;
+
+  g_return_if_fail (shader != NULL);
+  if (!_ensure_program (shader))
+    g_return_if_fail (shader->priv->program_handle);
+  priv = shader->priv;
+  gl = shader->context->gl_vtable;
+  g_return_if_fail (gl->BindFragDataLocation);
+
+  GST_TRACE_OBJECT (shader, "binding program %i frag data \'%s\' location %i",
+      (int) priv->program_handle, name, index);
+
+  gl->BindFragDataLocation (priv->program_handle, index, name);
+}
diff --git a/gst-libs/gst/gl/gstglshader.h b/gst-libs/gst/gl/gstglshader.h
index 21410e2..2200b89 100644
--- a/gst-libs/gst/gl/gstglshader.h
+++ b/gst-libs/gst/gl/gstglshader.h
@@ -104,6 +104,7 @@ void gst_gl_shader_set_uniform_matrix_4x3fv (GstGLShader *shader, const gchar *n
 
 gint gst_gl_shader_get_attribute_location  (GstGLShader *shader, const gchar *name);
 void gst_gl_shader_bind_attribute_location (GstGLShader * shader, guint index, const gchar * name);
+void gst_gl_shader_bind_frag_data_location (GstGLShader * shader, guint index, const gchar * name);
 
 G_END_DECLS
 
-- 
1.9.1