libobs/graphics: Add gs_texrender_get_format

libobs/graphics/graphics.h

@@ -464,6 +464,8 @@ EXPORT bool gs_texrender_begin(gs_texrender_t *texrender, uint32_t cx,
 EXPORT void gs_texrender_end(gs_texrender_t *texrender);
 EXPORT void gs_texrender_reset(gs_texrender_t *texrender);
 EXPORT gs_texture_t *gs_texrender_get_texture(const gs_texrender_t *texrender);
+EXPORT enum gs_color_format
+gs_texrender_get_format(const gs_texrender_t *texrender);
 
 /* ---------------------------------------------------
  * graphics subsystem

libobs/graphics/texture-render.c

@@ -140,3 +140,8 @@ gs_texture_t *gs_texrender_get_texture(const gs_texrender_t *texrender)
 {
 	return texrender ? texrender->target : NULL;
 }
+
+enum gs_color_format gs_texrender_get_format(const gs_texrender_t *texrender)
+{
+	return texrender->format;
+}