private static int blendColors(int color1, int color2, float factor) {
final float inverseFactor = 1f - factor;
float a = (Color.alpha(color1) * factor) + (Color.alpha(color2) * inverseFactor);
float r = (Color.red(color1) * factor) + (Color.red(color2) * inverseFactor);
float g = (Color.green(color1) * factor) + (Color.green(color2) * inverseFactor);
float b = (Color.blue(color1) * factor) + (Color.blue(color2) * inverseFactor);
return Color.argb((int) a, (int) r, (int) g, (int) b);
}
private int rotateColor(int color, float rad) {
float deg = rad * 180 / 3.1415927f;
int r = Color.red(color);
int g = Color.green(color);
int b = Color.blue(color);
ColorMatrix cm = new ColorMatrix();
ColorMatrix tmp = new ColorMatrix();
cm.setRGB2YUV();
tmp.setRotate(0, deg);
cm.postConcat(tmp);
tmp.setYUV2RGB();
cm.postConcat(tmp);
final float[] a = cm.getArray();
int ir = floatToByte(a[0] * r + a[1] * g + a[2] * b);
int ig = floatToByte(a[5] * r + a[6] * g + a[7] * b);
int ib = floatToByte(a[10] * r + a[11] * g + a[12] * b);
return Color.argb(
Color.alpha(color), pinToByte(ir),
pinToByte(ig), pinToByte(ib));
}
private int changeColorAlpha(int color, float value) {
int alpha = Math.round(Color.alpha(color) * value);
int red = Color.red(color);
int green = Color.green(color);
int blue = Color.blue(color);
return Color.argb(alpha, red, green, blue);
}
private int interpColor(int colors[], float unit) {
if (unit <= 0) {
return colors[0];
}
if (unit >= 1) {
return colors[colors.length - 1];
}
float p = unit * (colors.length - 1);
int i = (int) p;
p -= i;
// now p is just the fractional part [0...1) and i is the index
int c0 = colors[i];
int c1 = colors[i + 1];
int a = ave(Color.alpha(c0), Color.alpha(c1), p);
int r = ave(Color.red(c0), Color.red(c1), p);
int g = ave(Color.green(c0), Color.green(c1), p);
int b = ave(Color.blue(c0), Color.blue(c1), p);
return Color.argb(a, r, g, b);
}