diff options
| -rw-r--r-- | scumm/gfx.cpp | 108 |
1 files changed, 64 insertions, 44 deletions
diff --git a/scumm/gfx.cpp b/scumm/gfx.cpp index a56de5ed4f..aa74fa30bd 100644 --- a/scumm/gfx.cpp +++ b/scumm/gfx.cpp @@ -2557,62 +2557,82 @@ void Scumm::palManipulate() } } -void Scumm::unkRoomFunc3(int unk1, int unk2, int rfact, int gfact, int bfact) +void Scumm::unkRoomFunc3(int palstart, int palend, int rfact, int gfact, int bfact) { - byte *pal = _currentPalette; + byte *basepal = getPalettePtr(); + byte *pal = basepal; + byte *compareptr; byte *table = _shadowPalette; int i; - warning("unkRoomFunc3(%d,%d,%d,%d,%d): not fully implemented", unk1, unk2, rfact, gfact, bfact); - - // TODO - correctly implement this function (see also patch #588501) - // - // Some "typical" examples of how this function is being invoked in real life: - // - // 1) - // unkRoomFunc3(16, 255, 200, 200, 200) - // - // FOA: Sets up the colors for the boat and submarine shadows in the - // diving scene. Are the shadows too light? Maybe unk1 is used to - // darken the colors? - // - // 2) - // unkRoomFunc3(0, 255, 700, 700, 700) - // - // FOA: Sets up the colors for the subway car headlight when it first - // goes on. This seems to work ok. - // - // 3) - // unkRoomFunc3(160, 191, 300, 300, 300) - // unkRoomFunc3(160, 191, 289, 289, 289) - // ... - // unkRoomFunc3(160, 191, 14, 14, 14) - // unkRoomFunc3(160, 191, 3, 3, 3) - // - // 4) - // FOA: Sets up the colors for the subway car headlight for the later - // half of the trip, where it fades out. This currently doesn't work - // at all. The colors are too dark to be brightened. At first I thought - // unk1 and unk2 were used to tell which color interval to manipulate, - // but as far as I can tell the colors 160-191 aren't used at all to - // draw the light, that can't be it. Apparently unk1 and/or unk2 are - // used to brighten the colors. + // This is a correction of the patch supplied for BUG #588501. + // It has been tested in all four known rooms where unkRoomFunc3 is used: // - // 5) - // unkRoomFunc3(16,255,500,500,500) + // 1) FOA Room 53: subway departing Knossos for Atlantis. + // 2) FOA Room 48: subway crashing into the Atlantis entrance area + // 3) FOA Room 82: boat/sub shadows while diving near Thera + // 4) FOA Room 23: the big machine room inside Atlantis // - // FOA: Used in the Inner Sanctum after you activated the machine using the - // stone discs (briefly before the Nazis arrive). No idea at all if it is - // right here; also note that palManipulateInit() is called at the same time. + // The implementation behaves well in all tests. + // Pixel comparisons show that the resulting palette entries being + // derived from the shadow palette generated here occassionally differ + // slightly from the ones derived in the LEC executable. + // Not sure yet why, but the differences are VERY minor. // - // - + // There seems to be no explanation for why this function is called + // from within Room 23 (the big machine), as it has no shadow effects + // and thus doesn't result in any visual differences. + for (i = 0; i <= 255; i++) { int r = (int) (*pal++ * rfact) >> 8; int g = (int) (*pal++ * gfact) >> 8; int b = (int) (*pal++ * bfact) >> 8; - *table++ = remapPaletteColor(r, g, b, (uint) -1); + // The following functionality is similar to remapPaletteColor, except + // 1) we have to work off the original CLUT rather than the current palette, and + // 2) the target shadow palette entries must be bounded to the upper and lower + // bounds provided by the opcode. (This becomes significant in Room 48, but + // is not an issue in all other known case studies.) + int j; + int ar, ag, ab; + uint sum, diff, bestsum, bestitem = 0; + compareptr = basepal + palstart * 3; + + if (r > 255) + r = 255; + if (g > 255) + g = 255; + if (b > 255) + b = 255; + + bestsum = (uint) - 1; + + r &= ~3; + g &= ~3; + b &= ~3; + + for (j = palstart; j <= palend; j++, compareptr += 3) { + ar = compareptr[0] & ~3; + ag = compareptr[1] & ~3; + ab = compareptr[2] & ~3; + if (ar == r && ag == g && ab == b) { + bestitem = j; + break; + } + + diff = ar - r; + sum = diff * diff * 3; + diff = ag - g; + sum += diff * diff * 6; + diff = ab - b; + sum += diff * diff * 2; + + if (sum < bestsum) { + bestsum = sum; + bestitem = j; + } + } + *table++ = bestitem; } } |