src/blitter/8bpp_optimized.cpp
changeset 6852 439563b70fd3
child 6855 ac13e9ecd231
equal deleted inserted replaced
6851:0a0a094fb9f1 6852:439563b70fd3
       
     1 #include "../stdafx.h"
       
     2 #include "../zoom.hpp"
       
     3 #include "../gfx.h"
       
     4 #include "../debug.h"
       
     5 #include "8bpp_optimized.hpp"
       
     6 
       
     7 static FBlitter_8bppOptimized iFBlitter_8bppOptimized;
       
     8 
       
     9 extern void* AllocSprite(size_t);
       
    10 
       
    11 void Blitter_8bppOptimized::Draw(Blitter::BlitterParams *bp, BlitterMode mode, ZoomLevel zoom)
       
    12 {
       
    13 	const byte *src, *src_next;
       
    14 	Pixel8 *dst, *dst_line;
       
    15 	uint offset = 0;
       
    16 
       
    17 	/* Find the offset of this zoom-level */
       
    18 	offset = ((const byte *)bp->sprite)[(int)zoom * 2] | ((const byte *)bp->sprite)[(int)zoom * 2 + 1] << 8;
       
    19 
       
    20 	/* Find where to start reading in the source sprite */
       
    21 	src = (const byte *)bp->sprite + offset;
       
    22 	dst_line = (Pixel8 *)bp->dst + bp->top * bp->pitch + bp->left;
       
    23 
       
    24 	/* Skip over the top lines in the source image */
       
    25 	for (int y = 0; y < bp->skip_top; y++) {
       
    26 		uint trans, pixels;
       
    27 		for (;;) {
       
    28 			trans = *src++;
       
    29 			pixels = *src++;
       
    30 			if (trans == 0 && pixels == 0) break;
       
    31 			src += pixels;
       
    32 		}
       
    33 	}
       
    34 
       
    35 	src_next = src;
       
    36 
       
    37 	for (int y = 0; y < bp->height; y++) {
       
    38 		dst = dst_line;
       
    39 		dst_line += bp->pitch;
       
    40 
       
    41 		uint skip_left = bp->skip_left;
       
    42 		int width = bp->width;
       
    43 
       
    44 		for (;;) {
       
    45 			src = src_next;
       
    46 			uint8 trans = *src++;
       
    47 			uint8 pixels = *src++;
       
    48 			src_next = src + pixels;
       
    49 			if (trans == 0 && pixels == 0) break;
       
    50 			if (width <= 0) continue;
       
    51 
       
    52 			if (skip_left != 0) {
       
    53 				if (skip_left < trans) {
       
    54 					trans -= skip_left;
       
    55 					skip_left = 0;
       
    56 				} else {
       
    57 					skip_left -= trans;
       
    58 					trans = 0;
       
    59 				}
       
    60 				if (skip_left < pixels) {
       
    61 					src += skip_left;
       
    62 					pixels -= skip_left;
       
    63 					skip_left = 0;
       
    64 				} else {
       
    65 					src += pixels;
       
    66 					skip_left -= pixels;
       
    67 					pixels = 0;
       
    68 				}
       
    69 			}
       
    70 			if (skip_left != 0) continue;
       
    71 
       
    72 			/* Skip transparent pixels */
       
    73 			dst += trans;
       
    74 			width -= trans;
       
    75 			if (width <= 0) continue;
       
    76 			if (pixels > width) pixels = width;
       
    77 			width -= pixels;
       
    78 
       
    79 			switch (mode) {
       
    80 				case BM_COLOUR_REMAP:
       
    81 					for (uint x = 0; x < pixels; x++) {
       
    82 						if (bp->remap[*src] != 0) *dst = bp->remap[*src];
       
    83 						dst++; src++;
       
    84 					}
       
    85 					break;
       
    86 
       
    87 				case BM_TRANSPARENT:
       
    88 					for (uint x = 0; x < pixels; x++) {
       
    89 						*dst = bp->remap[*dst];
       
    90 						dst++; src++;
       
    91 					}
       
    92 					break;
       
    93 
       
    94 				default:
       
    95 					memcpy(dst, src, pixels);
       
    96 					dst += pixels; src += pixels;
       
    97 					break;
       
    98 			}
       
    99 		}
       
   100 	}
       
   101 }
       
   102 
       
   103 Sprite *Blitter_8bppOptimized::Encode(SpriteLoader::Sprite *sprite)
       
   104 {
       
   105 	Sprite *dest_sprite;
       
   106 	byte *temp_dst;
       
   107 	uint memory = 0;
       
   108 	uint index = 0;
       
   109 
       
   110 	/* Make memory for all zoom-levels */
       
   111 	memory += (int)ZOOM_LVL_END * sizeof(uint16);
       
   112 	for (int i = 0; i < (int)ZOOM_LVL_END; i++) {
       
   113 		memory += UnScaleByZoom(sprite->height, (ZoomLevel)i) * UnScaleByZoom(sprite->width, (ZoomLevel)i);
       
   114 		index += 2;
       
   115 	}
       
   116 
       
   117 	/* We have no idea how much memory we really need, so just guess something */
       
   118 	memory *= 5;
       
   119 	temp_dst = MallocT<byte>(memory);
       
   120 
       
   121 	/* Make the sprites per zoom-level */
       
   122 	for (int i = 0; i < (int)ZOOM_LVL_END; i++) {
       
   123 		/* Store the scaled image */
       
   124 		const SpriteLoader::CommonPixel *src;
       
   125 
       
   126 		/* Store the index table */
       
   127 		temp_dst[i * 2] = index & 0xFF;
       
   128 		temp_dst[i * 2 + 1] = (index >> 8) & 0xFF;
       
   129 
       
   130 		byte *dst = &temp_dst[index];
       
   131 
       
   132 		for (int y = 0; y < UnScaleByZoom(sprite->height, (ZoomLevel)i); y++) {
       
   133 			uint trans = 0;
       
   134 			uint pixels = 0;
       
   135 			uint last_color = 0;
       
   136 			uint count_index = 0;
       
   137 			src = &sprite->data[ScaleByZoom(y, (ZoomLevel)i) * sprite->width];
       
   138 
       
   139 			for (int x = 0; x < UnScaleByZoom(sprite->width, (ZoomLevel)i); x++) {
       
   140 				uint color = 0;
       
   141 				int count = 0;
       
   142 
       
   143 				/* Get the color keeping in mind the zoom-level */
       
   144 				for (int j = 0; j < ScaleByZoom(1, (ZoomLevel)i); j++) {
       
   145 					if (src->m != 0) { color = src->m; count++; }
       
   146 					src++;
       
   147 				}
       
   148 				/* If more than 12.5% of the pixels are non-transparent, make thisone non-transparent too */
       
   149 				if (count < ScaleByZoom(1, (ZoomLevel)i) / 8) color = 0;
       
   150 
       
   151 				if (last_color == 0 || color == 0) {
       
   152 					if (count_index != 0) {
       
   153 						/* Write how many non-transparent bytes we get */
       
   154 						temp_dst[count_index] = pixels;
       
   155 						pixels = 0;
       
   156 						count_index = 0;
       
   157 					}
       
   158 					/* As long as we find transparency bytes, keep counting */
       
   159 					if (color == 0) {
       
   160 						last_color = 0;
       
   161 						trans++;
       
   162 						continue;
       
   163 					}
       
   164 					/* No longer transparency, so write the amount of transparent bytes */
       
   165 					*dst = trans;
       
   166 					dst++; index++;
       
   167 					trans = 0;
       
   168 					/* Reserve a byte for the pixel counter */
       
   169 					count_index = index;
       
   170 					dst++; index++;
       
   171 				}
       
   172 				last_color = color;
       
   173 				pixels++;
       
   174 				*dst = color;
       
   175 				dst++; index++;
       
   176 			}
       
   177 
       
   178 			if (count_index != 0) temp_dst[count_index] = pixels;
       
   179 
       
   180 			/* Write line-ending */
       
   181 			*dst = 0; dst++; index++;
       
   182 			*dst = 0; dst++; index++;
       
   183 		}
       
   184 	}
       
   185 
       
   186 	/* Safety check, to make sure we guessed the size correctly */
       
   187 	assert(index < memory);
       
   188 
       
   189 	/* Allocate the exact amount of memory we need */
       
   190 	dest_sprite = (Sprite *)AllocSprite(sizeof(*dest_sprite) + index);
       
   191 
       
   192 	dest_sprite->height = sprite->height;
       
   193 	dest_sprite->width  = sprite->width;
       
   194 	dest_sprite->x_offs = sprite->x_offs;
       
   195 	dest_sprite->y_offs = sprite->y_offs;
       
   196 	memcpy(dest_sprite->data, temp_dst, index);
       
   197 
       
   198 	return dest_sprite;
       
   199 }