/* _______ __ __ __ ______ __ __ _______ __ __
* / _____/\ / /\ / /\ / /\ / ____/\ / /\ / /\ / ___ /\ / |\/ /\
* / /\____\// / // / // / // /\___\// /_// / // /\_/ / // , |/ / /
* / / /__ / / // / // / // / / / ___ / // ___ / // /| ' / /
* / /_// /\ / /_// / // / // /_/_ / / // / // /\_/ / // / | / /
* /______/ //______/ //_/ //_____/\ /_/ //_/ //_/ //_/ //_/ /|_/ /
* \______\/ \______\/ \_\/ \_____\/ \_\/ \_\/ \_\/ \_\/ \_\/ \_\/
*
* Copyright (c) 2004 - 2008 Olof Naess�n and Per Larsson
*
*
* Per Larsson a.k.a finalman
* Olof Naess�n a.k.a jansem/yakslem
*
* Visit: http://guichan.sourceforge.net
*
* License: (BSD)
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name of Guichan nor the names of its contributors may
* be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef GCN_SDLPIXEL_HPP
#define GCN_SDLPIXEL_HPP
#include "SDL.h"
#include "guichan/color.hpp"
namespace gcn
{
/**
* Checks a pixels color of an SDL_Surface.
*
* @param surface an SDL_Surface where to check for a pixel color.
* @param x the x coordinate on the surface.
* @param y the y coordinate on the surface.
* @return a color of a pixel.
*/
inline const Color SDLgetPixel(SDL_Surface* surface, int x, int y)
{
int bpp = surface->format->BytesPerPixel;
SDL_LockSurface(surface);
Uint8 *p = (Uint8 *)surface->pixels + y * surface->pitch + x * bpp;
unsigned int color = 0;
switch(bpp)
{
case 1:
color = *p;
break;
case 2:
color = *(Uint16 *)p;
break;
case 3:
if(SDL_BYTEORDER == SDL_BIG_ENDIAN)
{
color = p[0] << 16 | p[1] << 8 | p[2];
}
else
{
color = p[0] | p[1] << 8 | p[2] << 16;
}
break;
case 4:
color = *(Uint32 *)p;
break;
}
unsigned char r,g,b,a;
SDL_GetRGBA(color, surface->format, &r, &g, &b, &a);
SDL_UnlockSurface(surface);
return Color(r,g,b,a);
}
/**
* Puts a pixel on an SDL_Surface.
*
* @param x the x coordinate on the surface.
* @param y the y coordinate on the surface.
* @param color the color the pixel should be in.
*/
inline void SDLputPixel(SDL_Surface* surface, int x, int y, const Color& color)
{
int bpp = surface->format->BytesPerPixel;
SDL_LockSurface(surface);
Uint8 *p = (Uint8 *)surface->pixels + y * surface->pitch + x * bpp;
Uint32 pixel = SDL_MapRGB(surface->format, color.r, color.g, color.b);
switch(bpp)
{
case 1:
*p = pixel;
break;
case 2:
*(Uint16 *)p = pixel;
break;
case 3:
if(SDL_BYTEORDER == SDL_BIG_ENDIAN)
{
p[0] = (pixel >> 16) & 0xff;
p[1] = (pixel >> 8) & 0xff;
p[2] = pixel & 0xff;
}
else
{
p[0] = pixel & 0xff;
p[1] = (pixel >> 8) & 0xff;
p[2] = (pixel >> 16) & 0xff;
}
break;
case 4:
*(Uint32 *)p = pixel;
break;
}
SDL_UnlockSurface(surface);
}
/**
* Blends two 32 bit colors together.
*
* @param src the source color.
* @param dst the destination color.
* @param a alpha.
*/
inline unsigned int SDLAlpha32(unsigned int src, unsigned int dst, unsigned char a)
{
unsigned int b = ((src & 0xff) * a + (dst & 0xff) * (255 - a)) >> 8;
unsigned int g = ((src & 0xff00) * a + (dst & 0xff00) * (255 - a)) >> 8;
unsigned int r = ((src & 0xff0000) * a + (dst & 0xff0000) * (255 - a)) >> 8;
return (b & 0xff) | (g & 0xff00) | (r & 0xff0000);
}
/**
* Blends two 16 bit colors together.
*
* @param src the source color.
* @param dst the destination color.
* @param a alpha.
*/
inline unsigned short SDLAlpha16(unsigned short src, unsigned short dst, unsigned char a, const SDL_PixelFormat *f)
{
unsigned int b = ((src & f->Rmask) * a + (dst & f->Rmask) * (255 - a)) >> 8;
unsigned int g = ((src & f->Gmask) * a + (dst & f->Gmask) * (255 - a)) >> 8;
unsigned int r = ((src & f->Bmask) * a + (dst & f->Bmask) * (255 - a)) >> 8;
return (unsigned short)((b & f->Rmask) | (g & f->Gmask) | (r & f->Bmask));
}
/*
typedef struct{
SDL_Palette *palette;
Uint8 BitsPerPixel;
Uint8 BytesPerPixel;
Uint32 Rmask, Gmask, Bmask, Amask;
Uint8 Rshift, Gshift, Bshift, Ashift;
Uint8 Rloss, Gloss, Bloss, Aloss;
Uint32 colorkey;
Uint8 alpha;
} SDL_PixelFormat;
*/
/**
* Puts a pixel on an SDL_Surface with alpha
*
* @param x the x coordinate on the surface.
* @param y the y coordinate on the surface.
* @param color the color the pixel should be in.
*/
inline void SDLputPixelAlpha(SDL_Surface* surface, int x, int y, const Color& color)
{
int bpp = surface->format->BytesPerPixel;
SDL_LockSurface(surface);
Uint8 *p = (Uint8 *)surface->pixels + y * surface->pitch + x * bpp;
Uint32 pixel = SDL_MapRGB(surface->format, color.r, color.g, color.b);
switch(bpp)
{
case 1:
*p = pixel;
break;
case 2:
*(Uint16 *)p = SDLAlpha16(pixel, *(Uint32 *)p, color.a, surface->format);
break;
case 3:
if(SDL_BYTEORDER == SDL_BIG_ENDIAN)
{
unsigned int r = (p[0] * (255 - color.a) + color.r * color.a) >> 8;
unsigned int g = (p[1] * (255 - color.a) + color.g * color.a) >> 8;
unsigned int b = (p[2] * (255 - color.a) + color.b * color.a) >> 8;
p[2] = b;
p[1] = g;
p[0] = r;
}
else
{
unsigned int r = (p[2] * (255 - color.a) + color.r * color.a) >> 8;
unsigned int g = (p[1] * (255 - color.a) + color.g * color.a) >> 8;
unsigned int b = (p[0] * (255 - color.a) + color.b * color.a) >> 8;
p[0] = b;
p[1] = g;
p[2] = r;
}
break;
case 4:
*(Uint32 *)p = SDLAlpha32(pixel, *(Uint32 *)p, color.a);
break;
}
SDL_UnlockSurface(surface);
}
}
#endif // end GCN_SDLPIXEL_HPP
