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| author | inmarket <andrewh@inmarket.com.au> | 2017-10-02 16:47:18 +1000 |
|---|---|---|
| committer | inmarket <andrewh@inmarket.com.au> | 2017-10-02 16:47:18 +1000 |
| commit | f9be386e52a745d19c880aa035c577bed3eb11c7 (patch) | |
| tree | cf1e220a134e3be514442d44588b9f91c0326931 | |
| parent | fdaf636b5f0c7ff5280438f524a07c29a2f7eea6 (diff) | |
| download | uGFX-f9be386e52a745d19c880aa035c577bed3eb11c7.tar.gz uGFX-f9be386e52a745d19c880aa035c577bed3eb11c7.tar.bz2 uGFX-f9be386e52a745d19c880aa035c577bed3eb11c7.zip | |
Add alpha blending support
| -rw-r--r-- | src/gdisp/gdisp.c | 60 | ||||
| -rw-r--r-- | src/gdisp/gdisp_colors.h | 9 |
2 files changed, 51 insertions, 18 deletions
diff --git a/src/gdisp/gdisp.c b/src/gdisp/gdisp.c index 1941bd88..3af31ac2 100644 --- a/src/gdisp/gdisp.c +++ b/src/gdisp/gdisp.c @@ -3649,26 +3649,54 @@ void gdispGDrawBox(GDisplay *g, coord_t x, coord_t y, coord_t cx, coord_t cy, co } #endif -color_t gdispBlendColor(color_t fg, color_t bg, uint8_t alpha) -{ - uint16_t fg_ratio = alpha + 1; - uint16_t bg_ratio = 256 - alpha; - uint16_t r, g, b; +#if GDISP_PIXELFORMAT == GDISP_PIXELFORMAT_RGB888 + // Special alpha hacked version. + // Note: this will still work with real RGB888 + color_t gdispBlendColor(color_t fg, color_t bg, uint8_t alpha) + { + uint16_t fg_ratio = alpha + 1; + uint16_t bg_ratio = 256 - alpha; + uint16_t a, r, g, b; + + a = ALPHA_OF(fg) * fg_ratio; + r = RED_OF(fg) * fg_ratio; + g = GREEN_OF(fg) * fg_ratio; + b = BLUE_OF(fg) * fg_ratio; + + a += ALPHA_OF(bg) * bg_ratio; + r += RED_OF(bg) * bg_ratio; + g += GREEN_OF(bg) * bg_ratio; + b += BLUE_OF(bg) * bg_ratio; + + a >>= 8; + r >>= 8; + g >>= 8; + b >>= 8; + + return ARGB2COLOR(a, r, g, b); + } +#else + color_t gdispBlendColor(color_t fg, color_t bg, uint8_t alpha) + { + uint16_t fg_ratio = alpha + 1; + uint16_t bg_ratio = 256 - alpha; + uint16_t r, g, b; - r = RED_OF(fg) * fg_ratio; - g = GREEN_OF(fg) * fg_ratio; - b = BLUE_OF(fg) * fg_ratio; + r = RED_OF(fg) * fg_ratio; + g = GREEN_OF(fg) * fg_ratio; + b = BLUE_OF(fg) * fg_ratio; - r += RED_OF(bg) * bg_ratio; - g += GREEN_OF(bg) * bg_ratio; - b += BLUE_OF(bg) * bg_ratio; + r += RED_OF(bg) * bg_ratio; + g += GREEN_OF(bg) * bg_ratio; + b += BLUE_OF(bg) * bg_ratio; - r >>= 8; - g >>= 8; - b >>= 8; + r >>= 8; + g >>= 8; + b >>= 8; - return RGB2COLOR(r, g, b); -} + return RGB2COLOR(r, g, b); + } +#endif color_t gdispContrastColor(color_t color) { uint16_t r, g, b; diff --git a/src/gdisp/gdisp_colors.h b/src/gdisp/gdisp_colors.h index 5bfcfca2..0973e561 100644 --- a/src/gdisp/gdisp_colors.h +++ b/src/gdisp/gdisp_colors.h @@ -330,9 +330,14 @@ typedef uint16_t colorformat; // Special hack to allow alpha on RGB888 #if GDISP_PIXELFORMAT == GDISP_PIXELFORMAT_RGB888 - #define GFXTRANSPARENT (0xFF000000) + #define COLOR_BITS_A 8 + #define COLOR_SHIFT_A 24 + #define ALPHA_OF(c) (((c)>>24) ^ 0xFF) + #define EXACT_ALPHA_OF(c) ALPHA_OF((c)) #define AHTML2COLOR(h) ((h) ^ 0xFF000000) - #define ARGB2COLOR(a,r,g,b) ((((COLOR_TYPE)(((a) ^ 0xFF) & 0xFF)) << 24) | RGB2COLOR_R(r) | RGB2COLOR_G(g) | RGB2COLOR_B(b)) + #define RGB2COLOR_A(a) (((COLOR_TYPE)(((a) ^ 0xFF) & 0xFF)) << 24) + #define ARGB2COLOR(a,r,g,b) (RGB2COLOR_A(a) | RGB2COLOR_R(r) | RGB2COLOR_G(g) | RGB2COLOR_B(b)) + #define GFXTRANSPARENT (0xFF000000) #endif //------------------------- |