glimagesink: clobber the alpha channel by default

this can be disabled with the ignore-alpha property
This commit is contained in:
Matthew Waters 2015-01-30 15:13:27 +11:00
parent b1aae5cb70
commit c827d1f804
2 changed files with 30 additions and 2 deletions

View file

@ -179,7 +179,8 @@ enum
PROP_FORCE_ASPECT_RATIO,
PROP_PIXEL_ASPECT_RATIO,
PROP_CONTEXT,
PROP_HANDLE_EVENTS
PROP_HANDLE_EVENTS,
PROP_IGNORE_ALPHA,
};
enum
@ -297,6 +298,11 @@ gst_glimage_sink_class_init (GstGLImageSinkClass * klass)
"When enabled, XEvents will be selected and handled", TRUE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_HANDLE_EVENTS,
g_param_spec_boolean ("ignore-alpha", "Ignore Alpha",
"When enabled, alpha will be ignored and converted to black", TRUE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gst_element_class_set_metadata (element_class, "OpenGL video sink",
"Sink/Video", "A videosink based on OpenGL",
"Julien Isorce <julien.isorce@gmail.com>");
@ -370,6 +376,7 @@ gst_glimage_sink_init (GstGLImageSink * glimage_sink)
glimage_sink->stored_buffer = NULL;
glimage_sink->redisplay_texture = 0;
glimage_sink->handle_events = TRUE;
glimage_sink->ignore_alpha = TRUE;
g_mutex_init (&glimage_sink->drawing_lock);
}
@ -406,6 +413,9 @@ gst_glimage_sink_set_property (GObject * object, guint prop_id,
gst_glimage_sink_handle_events (GST_VIDEO_OVERLAY (glimage_sink),
g_value_get_boolean (value));
break;
case PROP_IGNORE_ALPHA:
glimage_sink->ignore_alpha = g_value_get_boolean (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
@ -460,6 +470,9 @@ gst_glimage_sink_get_property (GObject * object, guint prop_id,
case PROP_HANDLE_EVENTS:
g_value_set_boolean (value, glimage_sink->handle_events);
break;
case PROP_IGNORE_ALPHA:
g_value_set_boolean (value, glimage_sink->ignore_alpha);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
@ -1372,11 +1385,22 @@ gst_glimage_sink_on_draw (GstGLImageSink * gl_sink)
GST_VIDEO_INFO_HEIGHT (&gl_sink->info), &do_redisplay);
if (!do_redisplay) {
gfloat alpha = gl_sink->ignore_alpha ? 1.0f : 0.0f;
GLushort indices[] = { 0, 1, 2, 0, 2, 3 };
gl->ClearColor (0.0, 0.0, 0.0, 0.0);
gl->ClearColor (0.0, 0.0, 0.0, alpha);
gl->Clear (GL_COLOR_BUFFER_BIT);
if (gl_sink->ignore_alpha) {
GLenum dst_func =
gl_sink->ignore_alpha ? GL_CONSTANT_COLOR : GL_ONE_MINUS_SRC_ALPHA;
gl->BlendColor (0.0, 0.0, 0.0, alpha);
gl->BlendFunc (GL_SRC_ALPHA, dst_func);
gl->BlendEquation (GL_FUNC_ADD);
gl->Enable (GL_BLEND);
}
gst_gl_shader_use (gl_sink->redisplay_shader);
if (gl->GenVertexArrays)
@ -1394,6 +1418,9 @@ gst_glimage_sink_on_draw (GstGLImageSink * gl_sink)
gl->BindVertexArray (0);
else
_unbind_buffer (gl_sink);
if (gl_sink->ignore_alpha)
gl->Disable (GL_BLEND);
}
/* end default opengl scene */
window->is_drawing = FALSE;

View file

@ -67,6 +67,7 @@ struct _GstGLImageSink
GstGLContext *context;
GstGLContext *other_context;
gboolean handle_events;
gboolean ignore_alpha;
GstGLUpload *upload;
GstGLColorConvert *convert;