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Update image.cpp to handle multiple image depths #2

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Update image.cpp to handle multiple image depths #2

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44 changes: 36 additions & 8 deletions Ep10Code/qbRayTrace/qbTextures/image.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -35,6 +35,40 @@ qbRT::Texture::Image::~Image()
}
}

// Source - https://stackoverflow.com/questions/53033971/how-to-get-the-color-of-a-specific-pixel-from-sdl-surface

Uint32 getpixel(SDL_Surface *surface, int x, int y)
{
int bpp = surface->format->BytesPerPixel;
/* Here p is the address to the pixel we want to retrieve */
Uint8 *p = (Uint8 *)surface->pixels + y * surface->pitch + x * bpp;

switch (bpp)
{
case 1:
return *p;
break;

case 2:
return *(Uint16 *)p;
break;

case 3:
if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
return p[0] << 16 | p[1] << 8 | p[2];
else
return p[0] | p[1] << 8 | p[2] << 16;
break;

case 4:
return *(Uint32 *)p;
break;

default:
return 0; /* shouldn't happen, but avoids warnings */
}
}

qbVector<double> qbRT::Texture::Image::GetColor(const qbVector<double> &uvCoords)
{
qbVector<double> outputColor {4};
Expand Down Expand Up @@ -90,14 +124,8 @@ qbVector<double> qbRT::Texture::Image::GetColor(const qbVector<double> &uvCoords
if ((x >= 0) && (x < m_xSize) && (y >= 0) && (y < m_ySize))
{
// Convert (x,y) to a linear index.
int pixelIndex = x + (y * (m_pitch / m_bytesPerPixel));

// Get a pointer to the pixel data.
uint32_t *pixels = (uint32_t *)m_imageSurface->pixels;

// Extract the current pixel value.
uint32_t currentPixel = pixels[pixelIndex];

uint32_t currentPixel = getPixel(m_imageSurface, x, y);

// Convert to RGB.
uint8_t r, g, b, a;
SDL_GetRGBA(currentPixel, m_imageSurface->format, &r, &g, &b, &a);
Expand Down