diff options
author | Jason Garrett-Glaser <darkshikari@gmail.com> | 2010-11-07 21:04:46 +0300 |
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committer | Jason Garrett-Glaser <darkshikari@gmail.com> | 2010-11-07 21:04:46 +0300 |
commit | 8ce803db51a28eb662b6271b2b223e0312bdb3d2 (patch) | |
tree | acbcd06fcaa05e82c9a5b4b12ab20ef0a523d3c6 /libavdevice | |
parent | 46db10ed0e04872eb9b003129f8395005c935ca4 (diff) |
Make x11grab cursor drawing suck less
This new version:
1. Works on 24-bit and 32-bit input, not just 32-bit.
2. Doesn't try to run on 16-bit or 8-bit, instead of outright crashing.
3. Does proper alpha-blending, so cursor shadows look correct.
4. Doesn't swap R and B.
Mostly fixes issue 1997.
Fixes issue 2056.
Originally committed as revision 25690 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavdevice')
-rw-r--r-- | libavdevice/x11grab.c | 35 |
1 files changed, 26 insertions, 9 deletions
diff --git a/libavdevice/x11grab.c b/libavdevice/x11grab.c index 1b58d44f2e..ee3b8e901e 100644 --- a/libavdevice/x11grab.c +++ b/libavdevice/x11grab.c @@ -256,7 +256,16 @@ paint_mouse_pointer(XImage *image, struct x11_grab *s) int x, y; int line, column; int to_line, to_column; - int image_addr, xcim_addr; + int pixstride = image->bits_per_pixel >> 3; + /* Warning: in its insanity, xlib provides unsigned image data through a + * char* pointer, so we have to make it uint8_t to make things not break. + * Anyone who performs further investigation of the xlib API likely risks + * permanent brain damage. */ + uint8_t *pix = image->data; + + /* Code doesn't currently support 16-bit or PAL8 */ + if (image->bits_per_pixel != 24 && image->bits_per_pixel != 32) + return; xcim = XFixesGetCursorImage(dpy); @@ -268,14 +277,22 @@ paint_mouse_pointer(XImage *image, struct x11_grab *s) for (line = FFMAX(y, y_off); line < to_line; line++) { for (column = FFMAX(x, x_off); column < to_column; column++) { - xcim_addr = (line - y) * xcim->width + column - x; - - if ((unsigned char)(xcim->pixels[xcim_addr] >> 24) != 0) { // skip fully transparent pixel - image_addr = ((line - y_off) * width + column - x_off) * 4; - - image->data[image_addr] = (unsigned char)(xcim->pixels[xcim_addr] >> 0); - image->data[image_addr+1] = (unsigned char)(xcim->pixels[xcim_addr] >> 8); - image->data[image_addr+2] = (unsigned char)(xcim->pixels[xcim_addr] >> 16); + int xcim_addr = (line - y) * xcim->width + column - x; + int image_addr = ((line - y_off) * width + column - x_off) * pixstride; + int r = (uint8_t)(xcim->pixels[xcim_addr] >> 0); + int g = (uint8_t)(xcim->pixels[xcim_addr] >> 8); + int b = (uint8_t)(xcim->pixels[xcim_addr] >> 16); + int a = (uint8_t)(xcim->pixels[xcim_addr] >> 24); + + if (a == 255) { + pix[image_addr+0] = r; + pix[image_addr+1] = g; + pix[image_addr+2] = b; + } else if (a) { + /* pixel values from XFixesGetCursorImage come premultiplied by alpha */ + pix[image_addr+0] = r + (pix[image_addr+0]*(255-a) + 255/2) / 255; + pix[image_addr+1] = g + (pix[image_addr+1]*(255-a) + 255/2) / 255; + pix[image_addr+2] = b + (pix[image_addr+2]*(255-a) + 255/2) / 255; } } } |