# 8bpp_optimized.cpp

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    00001 /* $Id: 8bpp_optimized.cpp 26541 2014-04-29 18:18:52Z frosch $ */
    00002
    00003 /*
    00004  * This file is part of OpenTTD.
    00005  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
    00006  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
    00007  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
    00008  */
    00009
    00012 #include "../stdafx.h"
    00013 #include "../zoom_func.h"
    00014 #include "../settings_type.h"
    00015 #include "../core/math_func.hpp"
    00016 #include "8bpp_optimized.hpp"
    00017
    00019 static FBlitter_8bppOptimized iFBlitter_8bppOptimized;
    00020
    00021 void Blitter_8bppOptimized::Draw(Blitter::BlitterParams *bp, BlitterMode mode, ZoomLevel zoom)
    00022 {
    00023   /* Find the offset of this zoom-level */
    00024   const SpriteData *sprite_src = (const SpriteData *)bp->sprite;
    00025   uint offset = sprite_src->offset[zoom];
    00026
    00027   /* Find where to start reading in the source sprite */
    00028   const uint8 *src = sprite_src->data + offset;
    00029   uint8 *dst_line = (uint8 *)bp->dst + bp->top * bp->pitch + bp->left;
    00030
    00031   /* Skip over the top lines in the source image */
    00032   for (int y = 0; y < bp->skip_top; y++) {
    00033     for (;;) {
    00034       uint trans = *src++;
    00035       uint pixels = *src++;
    00036       if (trans == 0 && pixels == 0) break;
    00037       src += pixels;
    00038     }
    00039   }
    00040
    00041   const uint8 *src_next = src;
    00042
    00043   for (int y = 0; y < bp->height; y++) {
    00044     uint8 *dst = dst_line;
    00045     dst_line += bp->pitch;
    00046
    00047     uint skip_left = bp->skip_left;
    00048     int width = bp->width;
    00049
    00050     for (;;) {
    00051       src = src_next;
    00052       uint trans = *src++;
    00053       uint pixels = *src++;
    00054       src_next = src + pixels;
    00055       if (trans == 0 && pixels == 0) break;
    00056       if (width <= 0) continue;
    00057
    00058       if (skip_left != 0) {
    00059         if (skip_left < trans) {
    00060           trans -= skip_left;
    00061           skip_left = 0;
    00062         } else {
    00063           skip_left -= trans;
    00064           trans = 0;
    00065         }
    00066         if (skip_left < pixels) {
    00067           src += skip_left;
    00068           pixels -= skip_left;
    00069           skip_left = 0;
    00070         } else {
    00071           src += pixels;
    00072           skip_left -= pixels;
    00073           pixels = 0;
    00074         }
    00075       }
    00076       if (skip_left != 0) continue;
    00077
    00078       /* Skip transparent pixels */
    00079       dst += trans;
    00080       width -= trans;
    00081       if (width <= 0 || pixels == 0) continue;
    00082       pixels = min<uint>(pixels, (uint)width);
    00083       width -= pixels;
    00084
    00085       switch (mode) {
    00086         case BM_COLOUR_REMAP:
    00087         case BM_CRASH_REMAP: {
    00088           const uint8 *remap = bp->remap;
    00089           do {
    00090             uint m = remap[*src];
    00091             if (m != 0) *dst = m;
    00092             dst++; src++;
    00093           } while (--pixels != 0);
    00094           break;
    00095         }
    00096
    00097         case BM_TRANSPARENT: {
    00098           const uint8 *remap = bp->remap;
    00099           src += pixels;
    00100           do {
    00101             *dst = remap[*dst];
    00102             dst++;
    00103           } while (--pixels != 0);
    00104           break;
    00105         }
    00106
    00107         default:
    00108           memcpy(dst, src, pixels);
    00109           dst += pixels; src += pixels;
    00110           break;
    00111       }
    00112     }
    00113   }
    00114 }
    00115
    00116 Sprite *Blitter_8bppOptimized::Encode(const SpriteLoader::Sprite *sprite, AllocatorProc *allocator)
    00117 {
    00118   /* Make memory for all zoom-levels */
    00119   uint memory = sizeof(SpriteData);
    00120
    00121   ZoomLevel zoom_min;
    00122   ZoomLevel zoom_max;
    00123
    00124   if (sprite->type == ST_FONT) {
    00125     zoom_min = ZOOM_LVL_NORMAL;
    00126     zoom_max = ZOOM_LVL_NORMAL;
    00127   } else {
    00128     zoom_min = _settings_client.gui.zoom_min;
    00129     zoom_max = _settings_client.gui.zoom_max;
    00130     if (zoom_max == zoom_min) zoom_max = ZOOM_LVL_MAX;
    00131   }
    00132
    00133   for (ZoomLevel i = zoom_min; i <= zoom_max; i++) {
    00134     memory += sprite[i].width * sprite[i].height;
    00135   }
    00136
    00137   /* We have no idea how much memory we really need, so just guess something */
    00138   memory *= 5;
    00139
    00140   /* Don't allocate memory each time, but just keep some
    00141    * memory around as this function is called quite often
    00142    * and the memory usage is quite low. */
    00143   static ReusableBuffer<byte> temp_buffer;
    00144   SpriteData *temp_dst = (SpriteData *)temp_buffer.Allocate(memory);
    00145   memset(temp_dst, 0, sizeof(*temp_dst));
    00146   byte *dst = temp_dst->data;
    00147
    00148   /* Make the sprites per zoom-level */
    00149   for (ZoomLevel i = zoom_min; i <= zoom_max; i++) {
    00150     /* Store the index table */
    00151     uint offset = dst - temp_dst->data;
    00152     temp_dst->offset[i] = offset;
    00153
    00154     /* cache values, because compiler can't cache it */
    00155     int scaled_height = sprite[i].height;
    00156     int scaled_width  = sprite[i].width;
    00157
    00158     for (int y = 0; y < scaled_height; y++) {
    00159       uint trans = 0;
    00160       uint pixels = 0;
    00161       uint last_colour = 0;
    00162       byte *count_dst = NULL;
    00163
    00164       /* Store the scaled image */
    00165       const SpriteLoader::CommonPixel *src = &sprite[i].data[y * sprite[i].width];
    00166
    00167       for (int x = 0; x < scaled_width; x++) {
    00168         uint colour = src++->m;
    00169
    00170         if (last_colour == 0 || colour == 0 || pixels == 255) {
    00171           if (count_dst != NULL) {
    00172             /* Write how many non-transparent bytes we get */
    00173             *count_dst = pixels;
    00174             pixels = 0;
    00175             count_dst = NULL;
    00176           }
    00177           /* As long as we find transparency bytes, keep counting */
    00178           if (colour == 0 && trans != 255) {
    00179             last_colour = 0;
    00180             trans++;
    00181             continue;
    00182           }
    00183           /* No longer transparency, so write the amount of transparent bytes */
    00184           *dst = trans;
    00185           dst++;
    00186           trans = 0;
    00187           /* Reserve a byte for the pixel counter */
    00188           count_dst = dst;
    00189           dst++;
    00190         }
    00191         last_colour = colour;
    00192         if (colour == 0) {
    00193           trans++;
    00194         } else {
    00195           pixels++;
    00196           *dst = colour;
    00197           dst++;
    00198         }
    00199       }
    00200
    00201       if (count_dst != NULL) *count_dst = pixels;
    00202
    00203       /* Write line-ending */
    00204       *dst = 0; dst++;
    00205       *dst = 0; dst++;
    00206     }
    00207   }
    00208
    00209   uint size = dst - (byte *)temp_dst;
    00210
    00211   /* Safety check, to make sure we guessed the size correctly */
    00212   assert(size < memory);
    00213
    00214   /* Allocate the exact amount of memory we need */
    00215   Sprite *dest_sprite = (Sprite *)allocator(sizeof(*dest_sprite) + size);
    00216
    00217   dest_sprite->height = sprite->height;
    00218   dest_sprite->width  = sprite->width;
    00219   dest_sprite->x_offs = sprite->x_offs;
    00220   dest_sprite->y_offs = sprite->y_offs;
    00221   memcpy(dest_sprite->data, temp_dst, size);
    00222
    00223   return dest_sprite;
    00224 }