OpenTTD-patches/src/blitter/32bpp_optimized.cpp

112 lines
3.5 KiB
C++

/* $Id$ */
/** @file 32bpp_optimized.cpp Implementation of the optimized 32 bpp blitter. */
#include "../stdafx.h"
#include "../zoom_func.h"
#include "../gfx_func.h"
#include "../debug.h"
#include "32bpp_optimized.hpp"
static FBlitter_32bppOptimized iFBlitter_32bppOptimized;
void Blitter_32bppOptimized::Draw(Blitter::BlitterParams *bp, BlitterMode mode, ZoomLevel zoom)
{
const SpriteLoader::CommonPixel *src, *src_line;
uint32 *dst, *dst_line;
/* Find where to start reading in the source sprite */
src_line = (const SpriteLoader::CommonPixel *)bp->sprite + (bp->skip_top * bp->sprite_width + bp->skip_left) * ScaleByZoom(1, zoom);
dst_line = (uint32 *)bp->dst + bp->top * bp->pitch + bp->left;
for (int y = 0; y < bp->height; y++) {
dst = dst_line;
dst_line += bp->pitch;
src = src_line;
src_line += bp->sprite_width * ScaleByZoom(1, zoom);
for (int x = 0; x < bp->width; x++) {
if (src->a == 0) {
/* src->r is 'misused' here to indicate how much more pixels are following with an alpha of 0 */
int skip = UnScaleByZoom(src->r, zoom);
dst += skip;
x += skip - 1;
src += ScaleByZoom(1, zoom) * skip;
continue;
}
switch (mode) {
case BM_COLOUR_REMAP:
/* In case the m-channel is zero, do not remap this pixel in any way */
if (src->m == 0) {
*dst = ComposeColourRGBA(src->r, src->g, src->b, src->a, *dst);
} else {
if (bp->remap[src->m] != 0) *dst = ComposeColourPA(this->LookupColourInPalette(bp->remap[src->m]), src->a, *dst);
}
break;
case BM_TRANSPARENT:
/* TODO -- We make an assumption here that the remap in fact is transparency, not some color.
* This is never a problem with the code we produce, but newgrfs can make it fail... or at least:
* we produce a result the newgrf maker didn't expect ;) */
/* Make the current color a bit more black, so it looks like this image is transparent */
*dst = MakeTransparent(*dst, 192);
break;
default:
*dst = ComposeColourRGBA(src->r, src->g, src->b, src->a, *dst);
break;
}
dst++;
src += ScaleByZoom(1, zoom);
}
}
}
Sprite *Blitter_32bppOptimized::Encode(SpriteLoader::Sprite *sprite, Blitter::AllocatorProc *allocator)
{
Sprite *dest_sprite;
SpriteLoader::CommonPixel *dst;
dest_sprite = (Sprite *)allocator(sizeof(*dest_sprite) + sprite->height * sprite->width * sizeof(SpriteLoader::CommonPixel));
dest_sprite->height = sprite->height;
dest_sprite->width = sprite->width;
dest_sprite->x_offs = sprite->x_offs;
dest_sprite->y_offs = sprite->y_offs;
dst = (SpriteLoader::CommonPixel *)dest_sprite->data;
memcpy(dst, sprite->data, sprite->height * sprite->width * sizeof(SpriteLoader::CommonPixel));
/* Skip to the end of the array, and work backwards to find transparent blocks */
dst = dst + sprite->height * sprite->width - 1;
for (uint y = sprite->height; y > 0; y--) {
int trans = 0;
/* Process sprite line backwards, to compute lengths of transparent blocks */
for (uint x = sprite->width; x > 0; x--) {
if (dst->a == 0) {
/* Save transparent block length in red channel; max value is 255 the red channel can contain */
if (trans < 255) trans++;
dst->r = trans;
dst->g = 0;
dst->b = 0;
dst->m = 0;
} else {
trans = 0;
if (dst->m != 0) {
/* Pre-convert the mapping channel to a RGB value */
uint color = this->LookupColourInPalette(dst->m);
dst->r = GB(color, 16, 8);
dst->g = GB(color, 8, 8);
dst->b = GB(color, 0, 8);
}
}
dst--;
}
}
return dest_sprite;
}