diff options
| author | Matthew Waters <matthew@centricular.com> | 2018-10-04 23:43:19 +1000 |
|---|---|---|
| committer | Matthew Waters <matthew@centricular.com> | 2018-10-04 23:43:19 +1000 |
| commit | 779d028f27b7bc6eb7abe841fe2cda97de3be983 (patch) | |
| tree | 3b2f42cc1262167327278dbcac3230590455f2e4 | |
| parent | d63add22d2fe190fd408395e3191a930a3766e23 (diff) | |
| download | gst-plugins-base-779d028f27b7bc6eb7abe841fe2cda97de3be983.tar.gz gst-plugins-base-779d028f27b7bc6eb7abe841fe2cda97de3be983.tar.xz | |
gl: use correct blend functions for unpremultiplied alpha
Fallback to the closest but incorrect values we had before if we can't
do this correctly.
| -rw-r--r-- | ext/gl/gstglimagesink.c | 9 | ||||
| -rw-r--r-- | ext/gl/gstgloverlay.c | 6 |
2 files changed, 13 insertions, 2 deletions
diff --git a/ext/gl/gstglimagesink.c b/ext/gl/gstglimagesink.c index c70cd5510..14e1c950a 100644 --- a/ext/gl/gstglimagesink.c +++ b/ext/gl/gstglimagesink.c @@ -2237,7 +2237,14 @@ gst_glimage_sink_on_draw (GstGLImageSink * gl_sink) if (gl_sink->ignore_alpha) { gl->BlendColor (0.0, 0.0, 0.0, alpha); - gl->BlendFunc (GL_SRC_ALPHA, GL_CONSTANT_COLOR); + if (gl->BlendFuncSeparate) { + gl->BlendFuncSeparate (GL_SRC_ALPHA, GL_CONSTANT_COLOR, GL_ONE, + GL_ONE_MINUS_SRC_ALPHA); + } else { + /* we don't have separate blend modes, perform something close to + * correct instead */ + gl->BlendFunc (GL_SRC_ALPHA, GL_CONSTANT_COLOR); + } gl->BlendEquation (GL_FUNC_ADD); gl->Enable (GL_BLEND); } diff --git a/ext/gl/gstgloverlay.c b/ext/gl/gstgloverlay.c index 864ea64da..59096cb32 100644 --- a/ext/gl/gstgloverlay.c +++ b/ext/gl/gstgloverlay.c @@ -530,7 +530,11 @@ gst_gl_overlay_callback (GstGLFilter * filter, GstGLMemory * in_tex, gst_gl_shader_set_uniform_1f (overlay->shader, "alpha", overlay->alpha); gl->Enable (GL_BLEND); - gl->BlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); + if (gl->BlendFuncSeparate) + gl->BlendFuncSeparate (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, + GL_ONE_MINUS_SRC_ALPHA); + else + gl->BlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); gl->BlendEquation (GL_FUNC_ADD); gl->DrawElements (GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, 0); |