From a7b40ce5a9d84182b40392665d3a11a69be90ebf Mon Sep 17 00:00:00 2001 From: Grigori Goronzy Date: Tue, 21 Jul 2009 03:06:05 +0200 Subject: Factor out bitmap buffer copy For clarity, factor out bitmap copying into a function. Do not pad the bitmap with stride in the last row; this can not by guaranteed anyway. Add a comment about this peculiarity to the API documentation in ass.h Idea by Evgeniy Stepanov. --- libass/ass.h | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'libass/ass.h') diff --git a/libass/ass.h b/libass/ass.h index b92960a..3c8c1f6 100644 --- a/libass/ass.h +++ b/libass/ass.h @@ -30,11 +30,21 @@ /* Libass renderer object. Contents are private. */ typedef struct ass_renderer_s ass_renderer_t; -/* A linked list of images produced by ass renderer. */ +/* + * A linked list of images produced by an ass renderer. + * + * These images have to be rendered in-order for the correct screen + * composition. The libass renderer clips these bitmaps to the frame size. + * w/h can be zero, in this case the bitmap should not be rendered at all. + * The last bitmap row is not guaranteed to be padded up to stride size, + * e.g. in the worst case a bitmap has the size stride * (h - 1) + w. + */ typedef struct ass_image_s { int w, h; // Bitmap width/height int stride; // Bitmap stride unsigned char *bitmap; // 1bpp stride*h alpha buffer + // Note: the last row may not be padded to + // bitmap stride! uint32_t color; // Bitmap color and alpha, RGBA int dst_x, dst_y; // Bitmap placement inside the video frame -- cgit v1.2.3