diff options
Diffstat (limited to 'include/plot_util.h')
-rw-r--r-- | include/plot_util.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/include/plot_util.h b/include/plot_util.h new file mode 100644 index 0000000..6565cb1 --- /dev/null +++ b/include/plot_util.h @@ -0,0 +1,24 @@ +/* alpha blend two pixels together */ +static inline nsfb_colour_t +nsfb_plot_ablend(nsfb_colour_t pixel, nsfb_colour_t scrpixel) +{ + int opacity = pixel >> 24; + int transp = 0x100 - opacity; + uint32_t rb, g; + + rb = ((pixel & 0xFF00FF) * opacity + + (scrpixel & 0xFF00FF) * transp) >> 8; + g = ((pixel & 0x00FF00) * opacity + + (scrpixel & 0x00FF00) * transp) >> 8; + + return (rb & 0xFF00FF) | (g & 0xFF00); +} + + +bool nsfb_plot_clip(const nsfb_bbox_t * restrict clip, nsfb_bbox_t * restrict rect); + +bool nsfb_plot_clip_ctx(nsfb_t *nsfb, nsfb_bbox_t * restrict rect); + +bool nsfb_plot_clip_line(const nsfb_bbox_t * restrict clip, nsfb_bbox_t * restrict line); + +bool nsfb_plot_clip_line_ctx(nsfb_t *nsfb, nsfb_bbox_t * restrict line); |