SDL framework can not show BMP files smaller than 20x20 pixels?
Does anybody know if there is a min. size limit for BMP files in SDL framework to show them?
I'm asking you this because I tried but can not show correctly BMP files that are less than 20x20 pixels.(I'm using SDL for C++).Code:
bool successCondition = false;
if (SDL_Init(SDL_INIT_VIDEO) != 0) {
printf("Unable to initialize SDL: %s\n", SDL_GetError());
return 1;
}
atexit(SDL_Quit);
SDL_Surface *screen;
screen = SDL_SetVideoMode(640, 480, 24, SDL_DOUBLEBUF);
if (screen == NULL) {
printf("Unable to set video mode: %s\n", SDL_GetError());
return 1;
}
// nueva imagen
Image* imgSmile = new Image("Images/smile.bmp");
SDL_Rect src, dest;
src.x = 0;
src.y = 0;
src.w = imgSmile->getWidth();
src.h = imgSmile->getHeight();
dest.x = 50;
dest.y = 20;
dest.w = imgSmile->getWidth();
dest.h = imgSmile->getHeight();
SDL_BlitSurface(imgSmile->getSDLSurface(), &src, screen, &dest);
SDL_Flip(screen);
// nueva imagen
Image* imgSmileRe = new Image("Images/smile.bmp");
// Achico la imagen
imgSmileRe->resize(10, 10);
// Pego la imagen en la pantalla
src.x = 0;
src.y = 0;
src.w = imgSmileRe->getWidth();
src.h = imgSmileRe->getHeight();
dest.x = 100;
dest.y = 20;
dest.w = imgSmileRe->getWidth();
dest.h = imgSmileRe->getHeight();
SDL_BlitSurface(imgSmileRe->getSDLSurface(), &src, screen, &dest);
SDL_Flip(screen);
//esperar para cerrar
SDL_Event e;
bool running = true;
while(running)
{
while(SDL_PollEvent(&e))
{
switch(e.type)
{
case SDL_QUIT:
running = false;
SDL_Quit();
break;
}
}
}
// libero memoria
free(imgSmile);
free(imgSmileRe);
successCondition = true;
return successCondition;
}
And the code for resize:
void Image::resize(int newWidth, int newHeight)
{
int widthSrc = this->getWidth();
int heightSrc = this->getHeight();
// Empty new image
Image* temp = new Image(newWidth, newHeight);
int posXDst = 0;
int posYDst = 0;
for(int posYSrc = 0; posYSrc < heightSrc ; posYSrc++){
for(int posXSrc = 0; posXSrc < widthSrc; posXSrc++){
posXDst = (posXSrc * newWidth) / widthSrc;
posYDst = (posYSrc * newHeight) / heightSrc;
Uint32 pixelImg = this->getPixel(posXSrc, posYSrc);
if( posXSrc > 0 && posYSrc > 0 && newWidth > widthSrc && newHeight > heightSrc ){
int fromY = (((posYSrc-1) * newHeight) / heightSrc);
int fromX = (((posXSrc-1) * newWidth) / widthSrc);
// interpolacion interna
for (int y = fromY; y <= posYDst; y++){
for (int x = fromX; x <= posXDst; x++){
// pixel y posicion superior izquierdo
Uint32 pixelSI = this->getPixel(posXSrc-1, posYSrc-1);
int xSI = ((posXSrc-1) * newWidth) / widthSrc;
int ySI = ((posYSrc-1) * newHeight) / heightSrc;
// pixel y posicion superior derecho
Uint32 pixelSD = this->getPixel(posXSrc, posYSrc-1);
int xSD = (posXSrc * newWidth) / widthSrc;
int ySD = ((posYSrc-1) * newHeight) / heightSrc;
// pixel y posicion inferior izquierdo
Uint32 pixelII = this->getPixel(posXSrc-1, posYSrc);
int xII = ((posXSrc-1) * newWidth) / widthSrc;
int yII = (posYSrc * newHeight) / heightSrc;
// obtengo el pixel interpolado
Uint32 interpolatedPixel = this->getInterpolatedPixel( pixelSI, xSI, ySI,
pixelSD, xSD, ySD,
pixelII, xII, yII,
pixelImg, posXDst, posYDst,
开发者_StackOverflow x, y, temp->getFormat());
// coloco el pixel en la imagen destino
temp->putPixel( interpolatedPixel, x, y );
}
}
}
// Pongo el pixel en las nuevas coordenadas
temp->putPixel( pixelImg, posXDst, posYDst);
}
}
this->copy(*temp);
free(temp);
}
Sorry for the spanish comments. I'm using windows xp/ 7 the image is a smiley face in 24bits BMP file aprox 20x20 pixels.
Theoreticaly, there is no limit for the BMP size (as far as SDL is concerned).
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