Skip allocating any display buffer and starting any threads

in case image buffer contains byte buffer only and it's
color space matches display space.

It was already check for this case, but it happened later
in color management routines, which is needed for saving
files, but not fast enough for realtime playback of 4K.

1 files changed, 8 insertions, 0 deletions

diff --git a/source/blender/imbuf/intern/colormanagement.c b/source/blender/imbuf/intern/colormanagement.c
index 10dc517f56a..505ba2599df 100644
--- a/source/blender/imbuf/intern/colormanagement.c
+++ b/source/blender/imbuf/intern/colormanagement.c
@@ -1853,6 +1853,14 @@ unsigned char *IMB_display_buffer_acquire(ImBuf *ibuf, const ColorManagedViewSet
 			applied_view_settings = &default_view_settings;
 		}
 
+		/* early out: no float buffer and byte buffer is already in display space,
+		 * let's just use if
+		 */
+		if (ibuf->rect_float == NULL && ibuf->rect_colorspace) {
+			if (is_ibuf_rect_in_display_space(ibuf, applied_view_settings, display_settings))
+				return (unsigned char *) ibuf->rect;
+		}
+
 		colormanage_view_settings_to_cache(&cache_view_settings, applied_view_settings);
 		colormanage_display_settings_to_cache(&cache_display_settings, display_settings);