Lines Matching defs:alpha

44  * 32-bit to/from 24-bit is also simple - we just drop the alpha channel.
885     const teken_attr_t *a, uint32_t alpha, bool cursor)
919 	alpha = alpha << 24;
920 	fgc |= alpha;
921 	bgc |= alpha;
1272  * Implements alpha blending for RGBA data, could use pixels for arguments,
1274  * The generic alpha blending is:
1275  * blend = alpha * fg + (1.0 - alpha) * bg.
1276  * Since our alpha is not from range [0..1], we scale appropriately.
1279 alpha_blend(uint8_t fg, uint8_t bg, uint8_t alpha)
1284 	if (alpha == 0)
1286 	if (alpha == 0xFF)
1288 	blend = (alpha * fg + (0xFF - alpha) * bg);
1298  * Implements alpha blending for RGBA data, could use pixels for arguments,
1300  * The generic alpha blending is:
1301  * blend = alpha * fg + (1.0 - alpha) * bg.
1302  * Since our alpha is not from range [0..1], we scale appropriately.
1319 	 * we only implement alpha blending for depth 32.