From 3948cd37973696dc319170877382676809659465 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Nicolai=20H=C3=A4hnle?= Date: Tue, 14 Jun 2016 20:03:53 +0200 Subject: [PATCH] st/mesa: use a single memcpy in st_ReadPixels when possible MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This avoids costly address recomputations, function overhead, and may trigger large copy optimizations. Reviewed-by: Brian Paul Reviewed-by: Marek Olšák --- src/mesa/state_tracker/st_cb_readpixels.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-) diff --git a/src/mesa/state_tracker/st_cb_readpixels.c b/src/mesa/state_tracker/st_cb_readpixels.c index 39d2274..77c6332 100644 --- a/src/mesa/state_tracker/st_cb_readpixels.c +++ b/src/mesa/state_tracker/st_cb_readpixels.c @@ -520,14 +520,21 @@ st_ReadPixels(struct gl_context *ctx, GLint x, GLint y, /* memcpy data into a user buffer */ { const uint bytesPerRow = width * util_format_get_blocksize(dst_format); - GLuint row; - - for (row = 0; row < (unsigned) height; row++) { - void *dest = _mesa_image_address2d(pack, pixels, - width, height, format, - type, row, 0); - memcpy(dest, map, bytesPerRow); - map += tex_xfer->stride; + const uint destStride = _mesa_image_row_stride(pack, width, format, type); + char *dest = _mesa_image_address2d(pack, pixels, + width, height, format, + type, 0, 0); + + if (tex_xfer->stride == bytesPerRow && destStride == bytesPerRow) { + memcpy(dest, map, bytesPerRow * height); + } else { + GLuint row; + + for (row = 0; row < (unsigned) height; row++) { + memcpy(dest, map, bytesPerRow); + map += tex_xfer->stride; + dest += destStride; + } } } -- 2.7.4