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/* Xpaint-image */
#include <Xpaint.h>
/*
* The key-word "ImageCreate" is reserved for user-defined image routines;
* Such a routine should create and process an image.
*
* Pixels are unsigned char arrays p[0]=red, p[1]=green, p[2]=blue
* (thus each value should be in the range 0..255)
*
* In the example below, p = output pixel pointer, a = alpha pixel pointer
* The procedure below just creates an image by mapping given functions
* as red, green, blue components...
*
*/
Image * ImageCreate()
{
Image * image;
unsigned char *p, *a;
int x, y, v;
image = ImageNew(600, 400);
/* Allocate alpha channel */
image->alpha = (unsigned char *)malloc(image->width*image->height);
for (y = 0; y < image->height; y++) {
for (x = 0; x < image->width; x++) {
p = ImagePixel(image, x, y);
p[0] = (x+y+x*(1000-x)/500)%256;
p[1] = y%256;
p[2] = x%256;
v = 255-((x-300)*(x-300)+(y-200)*(y-200))/500;
if (v<0) v = 0;
a = ImageAlphaPixel(image, x, y);
*a = (unsigned char) v;
}
}
return image;
}
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