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#include "stdio.h"
#include "stdlib.h"
#include "stdint.h"
/* method for 16bpp and above (>1 byte per pixel) */
void sprite_high_colour()
{
/*uint32_t imgSize = 8;*/ /* in bytes */
/* 0xddccbbaa 0xeeeeffff */
uint8_t img[] = {0xaa, 0xbb, 0xcc, 0xdd, 0xff, 0xff, 0xee, 0xee};
uint32_t widthPixels = 2;
uint32_t currentByteIndex = 0; /* only for standalone test -- fread() will maintain this */
uint32_t bpp = 24;
uint32_t bytesPerPixel = bpp >> 3; /* divide by 8 */
for (uint32_t x = 0; x < widthPixels; x++) {
uint32_t pixel = 0;
for (uint32_t j = 0; j < bytesPerPixel; j++) {
uint8_t b = img[currentByteIndex++];
pixel = pixel | (b << (j * 8));
}
printf("%x\n", pixel);
}
}
void sprite_low_colour()
{
uint8_t img[] = {0xab, 0xcd, 0x12, 0x34 };
uint32_t widthInBits = 32;
uint32_t currentByteIndex = 0; /* only for standalone test -- fread() will maintain this */
uint32_t bpp = 8;
uint32_t bitmask = (1 << bpp) - 1; /* creates a mask of 1s that is bpp bits wide */
uint8_t currentbyte = img[currentByteIndex++];
for (uint32_t x = 0; x < widthInBits; x+=bpp) {
uint32_t offset_into_byte = x % 8;
uint32_t pixel = (currentbyte & (bitmask << offset_into_byte)) >> offset_into_byte;
printf("%x\n", pixel);
if (offset_into_byte + bpp == 8) {
currentbyte = img[currentByteIndex++];
}
}
}
int main()
{
sprite_low_colour();
return EXIT_SUCCESS;
}
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