src/blitter/8bpp_optimized.cpp
branchNewGRF_ports
changeset 6720 35756db7e577
child 6872 1c4a4a609f85
equal deleted inserted replaced
6719:4cc327ad39d5 6720:35756db7e577
       
     1 /* $Id$ */
       
     2 
       
     3 /** @file 8bpp_optimized.cpp */
       
     4 
       
     5 #include "../stdafx.h"
       
     6 #include "../zoom.hpp"
       
     7 #include "../gfx.h"
       
     8 #include "../debug.h"
       
     9 #include "8bpp_optimized.hpp"
       
    10 
       
    11 static FBlitter_8bppOptimized iFBlitter_8bppOptimized;
       
    12 
       
    13 void Blitter_8bppOptimized::Draw(Blitter::BlitterParams *bp, BlitterMode mode, ZoomLevel zoom)
       
    14 {
       
    15 	const uint8 *src, *src_next;
       
    16 	uint8 *dst, *dst_line;
       
    17 	uint offset = 0;
       
    18 
       
    19 	/* Find the offset of this zoom-level */
       
    20 	offset = ((const uint8 *)bp->sprite)[(int)zoom * 2] | ((const byte *)bp->sprite)[(int)zoom * 2 + 1] << 8;
       
    21 
       
    22 	/* Find where to start reading in the source sprite */
       
    23 	src = (const uint8 *)bp->sprite + offset;
       
    24 	dst_line = (uint8 *)bp->dst + bp->top * bp->pitch + bp->left;
       
    25 
       
    26 	/* Skip over the top lines in the source image */
       
    27 	for (int y = 0; y < bp->skip_top; y++) {
       
    28 		uint trans, pixels;
       
    29 		for (;;) {
       
    30 			trans = *src++;
       
    31 			pixels = *src++;
       
    32 			if (trans == 0 && pixels == 0) break;
       
    33 			src += pixels;
       
    34 		}
       
    35 	}
       
    36 
       
    37 	src_next = src;
       
    38 
       
    39 	for (int y = 0; y < bp->height; y++) {
       
    40 		dst = dst_line;
       
    41 		dst_line += bp->pitch;
       
    42 
       
    43 		uint skip_left = bp->skip_left;
       
    44 		int width = bp->width;
       
    45 
       
    46 		for (;;) {
       
    47 			src = src_next;
       
    48 			uint8 trans = *src++;
       
    49 			uint8 pixels = *src++;
       
    50 			src_next = src + pixels;
       
    51 			if (trans == 0 && pixels == 0) break;
       
    52 			if (width <= 0) continue;
       
    53 
       
    54 			if (skip_left != 0) {
       
    55 				if (skip_left < trans) {
       
    56 					trans -= skip_left;
       
    57 					skip_left = 0;
       
    58 				} else {
       
    59 					skip_left -= trans;
       
    60 					trans = 0;
       
    61 				}
       
    62 				if (skip_left < pixels) {
       
    63 					src += skip_left;
       
    64 					pixels -= skip_left;
       
    65 					skip_left = 0;
       
    66 				} else {
       
    67 					src += pixels;
       
    68 					skip_left -= pixels;
       
    69 					pixels = 0;
       
    70 				}
       
    71 			}
       
    72 			if (skip_left != 0) continue;
       
    73 
       
    74 			/* Skip transparent pixels */
       
    75 			dst += trans;
       
    76 			width -= trans;
       
    77 			if (width <= 0) continue;
       
    78 			if (pixels > width) pixels = width;
       
    79 			width -= pixels;
       
    80 
       
    81 			switch (mode) {
       
    82 				case BM_COLOUR_REMAP:
       
    83 					for (uint x = 0; x < pixels; x++) {
       
    84 						if (bp->remap[*src] != 0) *dst = bp->remap[*src];
       
    85 						dst++; src++;
       
    86 					}
       
    87 					break;
       
    88 
       
    89 				case BM_TRANSPARENT:
       
    90 					for (uint x = 0; x < pixels; x++) {
       
    91 						*dst = bp->remap[*dst];
       
    92 						dst++; src++;
       
    93 					}
       
    94 					break;
       
    95 
       
    96 				default:
       
    97 					memcpy(dst, src, pixels);
       
    98 					dst += pixels; src += pixels;
       
    99 					break;
       
   100 			}
       
   101 		}
       
   102 	}
       
   103 }
       
   104 
       
   105 Sprite *Blitter_8bppOptimized::Encode(SpriteLoader::Sprite *sprite, Blitter::AllocatorProc *allocator)
       
   106 {
       
   107 	Sprite *dest_sprite;
       
   108 	byte *temp_dst;
       
   109 	uint memory = 0;
       
   110 	uint index = 0;
       
   111 
       
   112 	/* Make memory for all zoom-levels */
       
   113 	memory += (int)ZOOM_LVL_END * sizeof(uint16);
       
   114 	for (int i = 0; i < (int)ZOOM_LVL_END; i++) {
       
   115 		memory += UnScaleByZoom(sprite->height, (ZoomLevel)i) * UnScaleByZoom(sprite->width, (ZoomLevel)i);
       
   116 		index += 2;
       
   117 	}
       
   118 
       
   119 	/* We have no idea how much memory we really need, so just guess something */
       
   120 	memory *= 5;
       
   121 	temp_dst = MallocT<byte>(memory);
       
   122 
       
   123 	/* Make the sprites per zoom-level */
       
   124 	for (int i = 0; i < (int)ZOOM_LVL_END; i++) {
       
   125 		/* Store the scaled image */
       
   126 		const SpriteLoader::CommonPixel *src;
       
   127 
       
   128 		/* Store the index table */
       
   129 		temp_dst[i * 2] = index & 0xFF;
       
   130 		temp_dst[i * 2 + 1] = (index >> 8) & 0xFF;
       
   131 
       
   132 		byte *dst = &temp_dst[index];
       
   133 
       
   134 		for (int y = 0; y < UnScaleByZoom(sprite->height, (ZoomLevel)i); y++) {
       
   135 			uint trans = 0;
       
   136 			uint pixels = 0;
       
   137 			uint last_color = 0;
       
   138 			uint count_index = 0;
       
   139 			uint rx = 0;
       
   140 			src = &sprite->data[ScaleByZoom(y, (ZoomLevel)i) * sprite->width];
       
   141 
       
   142 			for (int x = 0; x < UnScaleByZoom(sprite->width, (ZoomLevel)i); x++) {
       
   143 				uint color = 0;
       
   144 
       
   145 				/* Get the color keeping in mind the zoom-level */
       
   146 				for (int j = 0; j < ScaleByZoom(1, (ZoomLevel)i); j++) {
       
   147 					if (src->m != 0) color = src->m;
       
   148 					src++;
       
   149 					rx++;
       
   150 					/* Because of the scaling it might happen we read outside the buffer. Avoid that. */
       
   151 					if (rx == sprite->width) break;
       
   152 				}
       
   153 
       
   154 				if (last_color == 0 || color == 0 || pixels == 255) {
       
   155 					if (count_index != 0) {
       
   156 						/* Write how many non-transparent bytes we get */
       
   157 						temp_dst[count_index] = pixels;
       
   158 						pixels = 0;
       
   159 						count_index = 0;
       
   160 					}
       
   161 					/* As long as we find transparency bytes, keep counting */
       
   162 					if (color == 0) {
       
   163 						last_color = 0;
       
   164 						trans++;
       
   165 						continue;
       
   166 					}
       
   167 					/* No longer transparency, so write the amount of transparent bytes */
       
   168 					*dst = trans;
       
   169 					dst++; index++;
       
   170 					trans = 0;
       
   171 					/* Reserve a byte for the pixel counter */
       
   172 					count_index = index;
       
   173 					dst++; index++;
       
   174 				}
       
   175 				last_color = color;
       
   176 				pixels++;
       
   177 				*dst = color;
       
   178 				dst++; index++;
       
   179 			}
       
   180 
       
   181 			if (count_index != 0) temp_dst[count_index] = pixels;
       
   182 
       
   183 			/* Write line-ending */
       
   184 			*dst = 0; dst++; index++;
       
   185 			*dst = 0; dst++; index++;
       
   186 		}
       
   187 	}
       
   188 
       
   189 	/* Safety check, to make sure we guessed the size correctly */
       
   190 	assert(index < memory);
       
   191 
       
   192 	/* Allocate the exact amount of memory we need */
       
   193 	dest_sprite = (Sprite *)allocator(sizeof(*dest_sprite) + index);
       
   194 
       
   195 	dest_sprite->height = sprite->height;
       
   196 	dest_sprite->width  = sprite->width;
       
   197 	dest_sprite->x_offs = sprite->x_offs;
       
   198 	dest_sprite->y_offs = sprite->y_offs;
       
   199 	memcpy(dest_sprite->data, temp_dst, index);
       
   200 	free(temp_dst);
       
   201 
       
   202 	return dest_sprite;
       
   203 }