diff options
Diffstat (limited to 'src/mame/video/tankbatt.cpp')
-rw-r--r-- | src/mame/video/tankbatt.cpp | 41 |
1 files changed, 17 insertions, 24 deletions
diff --git a/src/mame/video/tankbatt.cpp b/src/mame/video/tankbatt.cpp index baa0813a6a1..847bba56002 100644 --- a/src/mame/video/tankbatt.cpp +++ b/src/mame/video/tankbatt.cpp @@ -17,41 +17,34 @@ Convert the color PROMs into a more useable format. ***************************************************************************/ -PALETTE_INIT_MEMBER(tankbatt_state, tankbatt) +void tankbatt_state::tankbatt_palette(palette_device &palette) const { - const uint8_t *color_prom = memregion("proms")->base(); - int i; + uint8_t const *const color_prom = memregion("proms")->base(); - #define RES_1 0xc0 /* this is a guess */ - #define RES_2 0x3f /* this is a guess */ + constexpr int RES_1 = 0xc0; // this is a guess + constexpr int RES_2 = 0x3f; // this is a guess - /* create a lookup table for the palette */ - for (i = 0; i < 0x100; i++) + // create a lookup table for the palette + for (int i = 0; i < 0x100; i++) { - int bit0, bit1, bit2, bit3; - int r, g, b; + int const bit0 = BIT(color_prom[i], 0); // intensity + int const bit1 = BIT(color_prom[i], 1); // red + int const bit2 = BIT(color_prom[i], 2); // green + int const bit3 = BIT(color_prom[i], 3); // blue - bit0 = (color_prom[i] >> 0) & 0x01; /* intensity */ - bit1 = (color_prom[i] >> 1) & 0x01; /* red */ - bit2 = (color_prom[i] >> 2) & 0x01; /* green */ - bit3 = (color_prom[i] >> 3) & 0x01; /* blue */ + // red component + int const r = bit1 * (RES_1 + (RES_2 * bit0)); - /* red component */ - r = RES_1 * bit1; - if (bit1) r += RES_2 * bit0; + // green component + int const g = bit2 * (RES_1 + (RES_2 * bit0)); - /* green component */ - g = RES_1 * bit2; - if (bit2) g += RES_2 * bit0; - - /* blue component */ - b = RES_1 * bit3; - if (bit3) b += RES_2 * bit0; + // blue component + int const b = bit3 * (RES_1 + (RES_2 * bit0)); palette.set_indirect_color(i, rgb_t(r, g, b)); } - for (i = 0; i < 0x200; i += 2) + for (int i = 0; i < 0x200; i += 2) { palette.set_pen_indirect(i + 0, 0); palette.set_pen_indirect(i + 1, i >> 1); |