src/blitter/8bpp_base.cpp

   1 /* $Id$ */
   2
   3 /*
   4  * This file is part of OpenTTD.
   5  * 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.
   6  * 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.
   7  * 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/>.
   8  */
   9
  10 /** @file 8bpp_base.cpp Implementation of the base for all 8 bpp blitters. */
  11
  12 #include "../stdafx.h"
  13 #include "../gfx_func.h"
  14 #include "8bpp_base.hpp"
  15
  16 #include "../safeguards.h"
  17
  18 void Blitter_8bppBase::DrawColourMappingRect(void *dst, int width, int height, PaletteID pal)
  19 {
  20         const uint8 *ctab = GetNonSprite(pal, ST_RECOLOUR) + 1;
  21
  22         do {
  23                 for (int i = 0; i != width; i++) *((uint8 *)dst + i) = ctab[((uint8 *)dst)[i]];
  24                 dst = (uint8 *)dst + _screen.pitch;
  25         } while (--height);
  26 }
  27
  28 void *Blitter_8bppBase::MoveTo(void *video, int x, int y)
  29 {
  30         return (uint8 *)video + x + y * _screen.pitch;
  31 }
  32
  33 void Blitter_8bppBase::SetPixel(void *video, int x, int y, uint8 colour)
  34 {
  35         *((uint8 *)video + x + y * _screen.pitch) = colour;
  36 }
  37
  38 void Blitter_8bppBase::DrawRect(void *video, int width, int height, uint8 colour)
  39 {
  40         do {
  41                 memset(video, colour, width);
  42                 video = (uint8 *)video + _screen.pitch;
  43         } while (--height);
  44 }
  45
  46 void Blitter_8bppBase::CopyFromBuffer(void *video, const void *src, int width, int height)
  47 {
  48         uint8 *dst = (uint8 *)video;
  49         const uint8 *usrc = (const uint8 *)src;
  50
  51         for (; height > 0; height--) {
  52                 memcpy(dst, usrc, width * sizeof(uint8));
  53                 usrc += width;
  54                 dst += _screen.pitch;
  55         }
  56 }
  57
  58 void Blitter_8bppBase::CopyToBuffer(const void *video, void *dst, int width, int height)
  59 {
  60         uint8 *udst = (uint8 *)dst;
  61         const uint8 *src = (const uint8 *)video;
  62
  63         for (; height > 0; height--) {
  64                 memcpy(udst, src, width * sizeof(uint8));
  65                 src += _screen.pitch;
  66                 udst += width;
  67         }
  68 }
  69
  70 void Blitter_8bppBase::CopyImageToBuffer(const void *video, void *dst, int width, int height, int dst_pitch)
  71 {
  72         uint8 *udst = (uint8 *)dst;
  73         const uint8 *src = (const uint8 *)video;
  74
  75         for (; height > 0; height--) {
  76                 memcpy(udst, src, width * sizeof(uint8));
  77                 src += _screen.pitch;
  78                 udst += dst_pitch;
  79         }
  80 }
  81
  82 void Blitter_8bppBase::ScrollBuffer(void *video, int &left, int &top, int &width, int &height, int scroll_x, int scroll_y)
  83 {
  84         const uint8 *src;
  85         uint8 *dst;
  86
  87         if (scroll_y > 0) {
  88                 /* Calculate pointers */
  89                 dst = (uint8 *)video + left + (top + height - 1) * _screen.pitch;
  90                 src = dst - scroll_y * _screen.pitch;
  91
  92                 /* Decrease height and increase top */
  93                 top += scroll_y;
  94                 height -= scroll_y;
  95                 assert(height > 0);
  96
  97                 /* Adjust left & width */
  98                 if (scroll_x >= 0) {
  99                         dst += scroll_x;
 100                         left += scroll_x;
 101                         width -= scroll_x;
 102                 } else {
 103                         src -= scroll_x;
 104                         width += scroll_x;
 105                 }
 106
 107                 for (int h = height; h > 0; h--) {
 108                         memcpy(dst, src, width * sizeof(uint8));
 109                         src -= _screen.pitch;
 110                         dst -= _screen.pitch;
 111                 }
 112         } else {
 113                 /* Calculate pointers */
 114                 dst = (uint8 *)video + left + top * _screen.pitch;
 115                 src = dst - scroll_y * _screen.pitch;
 116
 117                 /* Decrease height. (scroll_y is <=0). */
 118                 height += scroll_y;
 119                 assert(height > 0);
 120
 121                 /* Adjust left & width */
 122                 if (scroll_x >= 0) {
 123                         dst += scroll_x;
 124                         left += scroll_x;
 125                         width -= scroll_x;
 126                 } else {
 127                         src -= scroll_x;
 128                         width += scroll_x;
 129                 }
 130
 131                 /* the y-displacement may be 0 therefore we have to use memmove,
 132                  * because source and destination may overlap */
 133                 for (int h = height; h > 0; h--) {
 134                         memmove(dst, src, width * sizeof(uint8));
 135                         src += _screen.pitch;
 136                         dst += _screen.pitch;
 137                 }
 138         }
 139 }
 140
 141 int Blitter_8bppBase::BufferSize(int width, int height)
 142 {
 143         return width * height;
 144 }
 145
 146 void Blitter_8bppBase::PaletteAnimate(const Palette &palette)
 147 {
 148         /* Video backend takes care of the palette animation */
 149 }
 150
 151 Blitter::PaletteAnimation Blitter_8bppBase::UsePaletteAnimation()
 152 {
 153         return Blitter::PALETTE_ANIMATION_VIDEO_BACKEND;
 154 }