gstreamer/ext/pango/gsttextrender.h
Sebastian Dröge 2ace14f613 pango: Create one context per instance and remove class mutex
PangoCairo is thread-safe as long as the context and fontmap are not
shared between threads. Previously each subclass had its own context and
a class mutex for this reason, but apart from hurting performance this
was also not completely safe yet: the same fontmap might've been used by
different classes from different threads as the thread-default fontmap
(at time of class initialization) was used.
2018-08-27 15:41:31 +03:00

106 lines
3.2 KiB
C

#ifndef __GST_TEXT_RENDER_H__
#define __GST_TEXT_RENDER_H__
#include <gst/gst.h>
#include <pango/pangocairo.h>
G_BEGIN_DECLS
#define GST_TYPE_TEXT_RENDER (gst_text_render_get_type())
#define GST_TEXT_RENDER(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),\
GST_TYPE_TEXT_RENDER, GstTextRender))
#define GST_TEXT_RENDER_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),\
GST_TYPE_TEXT_RENDER, GstTextRenderClass))
#define GST_TEXT_RENDER_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj),\
GST_TYPE_TEXT_RENDER, GstTextRenderClass))
#define GST_IS_TEXT_RENDER(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),\
GST_TYPE_TEXT_RENDER))
#define GST_IS_TEXT_RENDER_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),\
GST_TYPE_TEXT_RENDER))
typedef struct _GstTextRender GstTextRender;
typedef struct _GstTextRenderClass GstTextRenderClass;
/**
* GstTextRenderVAlign:
* @GST_TEXT_RENDER_VALIGN_BASELINE: draw text on the baseline
* @GST_TEXT_RENDER_VALIGN_BOTTOM: draw text on the bottom
* @GST_TEXT_RENDER_VALIGN_TOP: draw test on top
*
* Vertical alignment of the text.
*/
typedef enum {
GST_TEXT_RENDER_VALIGN_BASELINE,
GST_TEXT_RENDER_VALIGN_BOTTOM,
GST_TEXT_RENDER_VALIGN_TOP
} GstTextRenderVAlign;
/**
* GstTextRenderHAlign:
* @GST_TEXT_RENDER_HALIGN_LEFT: align text left
* @GST_TEXT_RENDER_HALIGN_CENTER: align text center
* @GST_TEXT_RENDER_HALIGN_RIGHT: align text right
*
* Horizontal alignment of the text.
*/
typedef enum {
GST_TEXT_RENDER_HALIGN_LEFT,
GST_TEXT_RENDER_HALIGN_CENTER,
GST_TEXT_RENDER_HALIGN_RIGHT
} GstTextRenderHAlign;
/**
* GstTextRenderLineAlign:
* @GST_TEXT_RENDER_LINE_ALIGN_LEFT: lines are left-aligned
* @GST_TEXT_RENDER_LINE_ALIGN_CENTER: lines are center-aligned
* @GST_TEXT_RENDER_LINE_ALIGN_RIGHT: lines are right-aligned
*
* Alignment of text lines relative to each other
*/
typedef enum {
GST_TEXT_RENDER_LINE_ALIGN_LEFT = PANGO_ALIGN_LEFT,
GST_TEXT_RENDER_LINE_ALIGN_CENTER = PANGO_ALIGN_CENTER,
GST_TEXT_RENDER_LINE_ALIGN_RIGHT = PANGO_ALIGN_RIGHT
} GstTextRenderLineAlign;
/**
* GstTextRender:
*
* Opaque textrender data structure.
*/
struct _GstTextRender {
GstElement element;
GstPad *sinkpad, *srcpad;
gint width;
gint height;
PangoLayout *layout;
gdouble shadow_offset;
gdouble outline_offset;
guchar *text_image;
gint image_width;
gint image_height;
gint baseline_y;
gboolean use_ARGB;
PangoContext *pango_context;
GstTextRenderVAlign valign;
GstTextRenderHAlign halign;
GstTextRenderLineAlign line_align;
gint xpad;
gint ypad;
GstEvent *segment_event;
};
struct _GstTextRenderClass {
GstElementClass parent_class;
};
GType gst_text_render_get_type(void) G_GNUC_CONST;
G_END_DECLS
#endif /* __GST_TEXT_RENDER_H */