# 8bpp_base.cpp

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    00001 /* $Id: 8bpp_base.cpp 18907 2010-01-23 22:37:14Z alberth $ */
    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, PaletteID 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::DrawRect(void *video, int width, int height, uint8 colour)
    00037 {
    00038   do {
    00039     memset(video, colour, width);
    00040     video = (uint8 *)video + _screen.pitch;
    00041   } while (--height);
    00042 }
    00043
    00044 void Blitter_8bppBase::DrawLine(void *video, int x, int y, int x2, int y2, int screen_width, int screen_height, uint8 colour)
    00045 {
    00046   int dy;
    00047   int dx;
    00048   int stepx;
    00049   int stepy;
    00050   int frac;
    00051
    00052   dy = (y2 - y) * 2;
    00053   if (dy < 0) {
    00054     dy = -dy;
    00055     stepy = -1;
    00056   } else {
    00057     stepy = 1;
    00058   }
    00059
    00060   dx = (x2 - x) * 2;
    00061   if (dx < 0) {
    00062     dx = -dx;
    00063     stepx = -1;
    00064   } else {
    00065     stepx = 1;
    00066   }
    00067
    00068   if (x >= 0 && y >= 0 && x < screen_width && y < screen_height) this->SetPixel(video, x, y, colour);
    00069   if (dx > dy) {
    00070     frac = dy - (dx / 2);
    00071     while (x != x2) {
    00072       if (frac >= 0) {
    00073         y += stepy;
    00074         frac -= dx;
    00075       }
    00076       x += stepx;
    00077       frac += dy;
    00078       if (x >= 0 && y >= 0 && x < screen_width && y < screen_height) this->SetPixel(video, x, y, colour);
    00079     }
    00080   } else {
    00081     frac = dx - (dy / 2);
    00082     while (y != y2) {
    00083       if (frac >= 0) {
    00084         x += stepx;
    00085         frac -= dy;
    00086       }
    00087       y += stepy;
    00088       frac += dx;
    00089       if (x >= 0 && y >= 0 && x < screen_width && y < screen_height) this->SetPixel(video, x, y, colour);
    00090     }
    00091   }
    00092 }
    00093
    00094 void Blitter_8bppBase::CopyFromBuffer(void *video, const void *src, int width, int height)
    00095 {
    00096   uint8 *dst = (uint8 *)video;
    00097   uint8 *usrc = (uint8 *)src;
    00098
    00099   for (; height > 0; height--) {
    00100     memcpy(dst, usrc, width * sizeof(uint8));
    00101     usrc += width;
    00102     dst += _screen.pitch;
    00103   }
    00104 }
    00105
    00106 void Blitter_8bppBase::CopyToBuffer(const void *video, void *dst, int width, int height)
    00107 {
    00108   uint8 *udst = (uint8 *)dst;
    00109   uint8 *src = (uint8 *)video;
    00110
    00111   for (; height > 0; height--) {
    00112     memcpy(udst, src, width * sizeof(uint8));
    00113     src += _screen.pitch;
    00114     udst += width;
    00115   }
    00116 }
    00117
    00118 void Blitter_8bppBase::CopyImageToBuffer(const void *video, void *dst, int width, int height, int dst_pitch)
    00119 {
    00120   uint8 *udst = (uint8 *)dst;
    00121   uint8 *src = (uint8 *)video;
    00122
    00123   for (; height > 0; height--) {
    00124     memcpy(udst, src, width * sizeof(uint8));
    00125     src += _screen.pitch;
    00126     udst += dst_pitch;
    00127   }
    00128 }
    00129
    00130 void Blitter_8bppBase::ScrollBuffer(void *video, int &left, int &top, int &width, int &height, int scroll_x, int scroll_y)
    00131 {
    00132   const uint8 *src;
    00133   uint8 *dst;
    00134
    00135   if (scroll_y > 0) {
    00136     /* Calculate pointers */
    00137     dst = (uint8 *)video + left + (top + height - 1) * _screen.pitch;
    00138     src = dst - scroll_y * _screen.pitch;
    00139
    00140     /* Decrease height and increase top */
    00141     top += scroll_y;
    00142     height -= scroll_y;
    00143     assert(height > 0);
    00144
    00145     /* Adjust left & width */
    00146     if (scroll_x >= 0) {
    00147       dst += scroll_x;
    00148       left += scroll_x;
    00149       width -= scroll_x;
    00150     } else {
    00151       src -= scroll_x;
    00152       width += scroll_x;
    00153     }
    00154
    00155     for (int h = height; h > 0; h--) {
    00156       memcpy(dst, src, width * sizeof(uint8));
    00157       src -= _screen.pitch;
    00158       dst -= _screen.pitch;
    00159     }
    00160   } else {
    00161     /* Calculate pointers */
    00162     dst = (uint8 *)video + left + top * _screen.pitch;
    00163     src = dst - scroll_y * _screen.pitch;
    00164
    00165     /* Decrese height. (scroll_y is <=0). */
    00166     height += scroll_y;
    00167     assert(height > 0);
    00168
    00169     /* Adjust left & width */
    00170     if (scroll_x >= 0) {
    00171       dst += scroll_x;
    00172       left += scroll_x;
    00173       width -= scroll_x;
    00174     } else {
    00175       src -= scroll_x;
    00176       width += scroll_x;
    00177     }
    00178
    00179     /* the y-displacement may be 0 therefore we have to use memmove,
    00180      * because source and destination may overlap */
    00181     for (int h = height; h > 0; h--) {
    00182       memmove(dst, src, width * sizeof(uint8));
    00183       src += _screen.pitch;
    00184       dst += _screen.pitch;
    00185     }
    00186   }
    00187 }
    00188
    00189 int Blitter_8bppBase::BufferSize(int width, int height)
    00190 {
    00191   return width * height;
    00192 }
    00193
    00194 void Blitter_8bppBase::PaletteAnimate(uint start, uint count)
    00195 {
    00196   /* Video backend takes care of the palette animation */
    00197 }
    00198
    00199 Blitter::PaletteAnimation Blitter_8bppBase::UsePaletteAnimation()
    00200 {
    00201   return Blitter::PALETTE_ANIMATION_VIDEO_BACKEND;
    00202 }