void bicubic_interpolation(struct ImBuf *in, struct ImBuf *out, float u, float v, int xout, int yout);
void neareast_interpolation(struct ImBuf *in, struct ImBuf *out, float u, float v, int xout, int yout);
void bilinear_interpolation(struct ImBuf *in, struct ImBuf *out, float u, float v, int xout, int yout);
Added...
void bicubic_interpolation_color(struct ImBuf *in, unsigned char *col, float *col_float, float u, float v);
void neareast_interpolation_color(struct ImBuf *in, unsigned char *col, float *col_float, float u, float v);
void bilinear_interpolation_color(struct ImBuf *in, unsigned char *col, float *col_float, float u, float v);
This is needed so for projection painting but generally useful if you want to get the interpolated color of a pixel in an image without having a destination imbuf.
While editing these I noticed the functons are a bit dodgy, they assume the input ImBuf has matching float/chr buffer to the output.
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