# 8bpp_base.cpp

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    00001 /* $Id: 8bpp_base.cpp 17248 2009-08-21 20:21:05Z rubidium $ */
    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 "../gfx_func.h"
    00014 #include "8bpp_base.hpp"
    00015
    00016 void Blitter_8bppBase::DrawColourMappingRect(void *dst, int width, int height, int pal)
    00017 {
    00018   const uint8 *ctab = GetNonSprite(pal, ST_RECOLOUR) + 1;
    00019
    00020   do {
    00021     for (int i = 0; i != width; i++) *((uint8 *)dst + i) = ctab[((uint8 *)dst)[i]];
    00022     dst = (uint8 *)dst + _screen.pitch;
    00023   } while (--height);
    00024 }
    00025
    00026 void *Blitter_8bppBase::MoveTo(const void *video, int x, int y)
    00027 {
    00028   return (uint8 *)video + x + y * _screen.pitch;
    00029 }
    00030
    00031 void Blitter_8bppBase::SetPixel(void *video, int x, int y, uint8 colour)
    00032 {
    00033   *((uint8 *)video + x + y * _screen.pitch) = colour;
    00034 }
    00035
    00036 void Blitter_8bppBase::SetPixelIfEmpty(void *video, int x, int y, uint8 colour)
    00037 {
    00038   uint8 *dst = (uint8 *)video + x + y * _screen.pitch;
    00039   if (*dst == 0) *dst = colour;
    00040 }
    00041
    00042 void Blitter_8bppBase::DrawRect(void *video, int width, int height, uint8 colour)
    00043 {
    00044   do {
    00045     memset(video, colour, width);
    00046     video = (uint8 *)video + _screen.pitch;
    00047   } while (--height);
    00048 }
    00049
    00050 void Blitter_8bppBase::DrawLine(void *video, int x, int y, int x2, int y2, int screen_width, int screen_height, uint8 colour)
    00051 {
    00052   int dy;
    00053   int dx;
    00054   int stepx;
    00055   int stepy;
    00056   int frac;
    00057
    00058   dy = (y2 - y) * 2;
    00059   if (dy < 0) {
    00060     dy = -dy;
    00061     stepy = -1;
    00062   } else {
    00063     stepy = 1;
    00064   }
    00065
    00066   dx = (x2 - x) * 2;
    00067   if (dx < 0) {
    00068     dx = -dx;
    00069     stepx = -1;
    00070   } else {
    00071     stepx = 1;
    00072   }
    00073
    00074   if (x >= 0 && y >= 0 && x < screen_width && y < screen_height) this->SetPixel(video, x, y, colour);
    00075   if (dx > dy) {
    00076     frac = dy - (dx / 2);
    00077     while (x != x2) {
    00078       if (frac >= 0) {
    00079         y += stepy;
    00080         frac -= dx;
    00081       }
    00082       x += stepx;
    00083       frac += dy;
    00084       if (x >= 0 && y >= 0 && x < screen_width && y < screen_height) this->SetPixel(video, x, y, colour);
    00085     }
    00086   } else {
    00087     frac = dx - (dy / 2);
    00088     while (y != y2) {
    00089       if (frac >= 0) {
    00090         x += stepx;
    00091         frac -= dy;
    00092       }
    00093       y += stepy;
    00094       frac += dx;
    00095       if (x >= 0 && y >= 0 && x < screen_width && y < screen_height) this->SetPixel(video, x, y, colour);
    00096     }
    00097   }
    00098 }
    00099
    00100 void Blitter_8bppBase::CopyFromBuffer(void *video, const void *src, int width, int height)
    00101 {
    00102   uint8 *dst = (uint8 *)video;
    00103   uint8 *usrc = (uint8 *)src;
    00104
    00105   for (; height > 0; height--) {
    00106     memcpy(dst, usrc, width * sizeof(uint8));
    00107     usrc += width;
    00108     dst += _screen.pitch;
    00109   }
    00110 }
    00111
    00112 void Blitter_8bppBase::CopyToBuffer(const void *video, void *dst, int width, int height)
    00113 {
    00114   uint8 *udst = (uint8 *)dst;
    00115   uint8 *src = (uint8 *)video;
    00116
    00117   for (; height > 0; height--) {
    00118     memcpy(udst, src, width * sizeof(uint8));
    00119     src += _screen.pitch;
    00120     udst += width;
    00121   }
    00122 }
    00123
    00124 void Blitter_8bppBase::CopyImageToBuffer(const void *video, void *dst, int width, int height, int dst_pitch)
    00125 {
    00126   uint8 *udst = (uint8 *)dst;
    00127   uint8 *src = (uint8 *)video;
    00128
    00129   for (; height > 0; height--) {
    00130     memcpy(udst, src, width * sizeof(uint8));
    00131     src += _screen.pitch;
    00132     udst += dst_pitch;
    00133   }
    00134 }
    00135
    00136 void Blitter_8bppBase::ScrollBuffer(void *video, int &left, int &top, int &width, int &height, int scroll_x, int scroll_y)
    00137 {
    00138   const uint8 *src;
    00139   uint8 *dst;
    00140
    00141   if (scroll_y > 0) {
    00142     /* Calculate pointers */
    00143     dst = (uint8 *)video + left + (top + height - 1) * _screen.pitch;
    00144     src = dst - scroll_y * _screen.pitch;
    00145
    00146     /* Decrease height and increase top */
    00147     top += scroll_y;
    00148     height -= scroll_y;
    00149     assert(height > 0);
    00150
    00151     /* Adjust left & width */
    00152     if (scroll_x >= 0) {
    00153       dst += scroll_x;
    00154       left += scroll_x;
    00155       width -= scroll_x;
    00156     } else {
    00157       src -= scroll_x;
    00158       width += scroll_x;
    00159     }
    00160
    00161     for (int h = height; h > 0; h--) {
    00162       memcpy(dst, src, width * sizeof(uint8));
    00163       src -= _screen.pitch;
    00164       dst -= _screen.pitch;
    00165     }
    00166   } else {
    00167     /* Calculate pointers */
    00168     dst = (uint8 *)video + left + top * _screen.pitch;
    00169     src = dst - scroll_y * _screen.pitch;
    00170
    00171     /* Decrese height. (scroll_y is <=0). */
    00172     height += scroll_y;
    00173     assert(height > 0);
    00174
    00175     /* Adjust left & width */
    00176     if (scroll_x >= 0) {
    00177       dst += scroll_x;
    00178       left += scroll_x;
    00179       width -= scroll_x;
    00180     } else {
    00181       src -= scroll_x;
    00182       width += scroll_x;
    00183     }
    00184
    00185     /* the y-displacement may be 0 therefore we have to use memmove,
    00186      * because source and destination may overlap */
    00187     for (int h = height; h > 0; h--) {
    00188       memmove(dst, src, width * sizeof(uint8));
    00189       src += _screen.pitch;
    00190       dst += _screen.pitch;
    00191     }
    00192   }
    00193 }
    00194
    00195 int Blitter_8bppBase::BufferSize(int width, int height)
    00196 {
    00197   return width * height;
    00198 }
    00199
    00200 void Blitter_8bppBase::PaletteAnimate(uint start, uint count)
    00201 {
    00202   /* Video backend takes care of the palette animation */
    00203 }
    00204
    00205 Blitter::PaletteAnimation Blitter_8bppBase::UsePaletteAnimation()
    00206 {
    00207   return Blitter::PALETTE_ANIMATION_VIDEO_BACKEND;
    00208 }