I'm trying to make a gradient effect. I want to make a method that returns returns a color for a position on a gradient. So for example, if variable "x" can be anything from 0 to 9, if x was 0 I might want the method to return black. If x was 9, I might want it to return white, and if x was 2 I mighy want the function to return a dark gray. The colors don't have to be white and black, but any two colors. (The method would return a "Color" from the Java Color class)

I tried to make a weighted average for each rgb value and put them back together, but it doesn't work properly. The colors don't mix properly



"length" is the length of the gradient, which was 9 in the above example, and color1 might be white and color2 might be black

Thanks

Right, but that only works for black and white. In my applet I'm using many more colors and need a general solution for them.

Oh... I put in "return new Color( (r << 16) | (g << | b )" and it worked. Huh... I had only read about these bit-wise operators and never used them. I wonder why my implementation didn't work... Oh well, probably just messed up the math. Anyway, it works now. Thanks!

An int can hold 32 bits of data. 32 bits == 4 bytes. Which further equals 1 int (I.e, an int is made up of 4 bytes).

A pixel/color is a bucket of data that holds 3 colours: Red, Green and Blue. Why? Because using those 3 colours we can trick the human eye to see over 16 million different colours (255 * 255 * 255).


So because an int can hold up to 4 bytes a pixel is usually represented as an int. Sometimes the last byte is used for transparency (Alpha).

You are saving the r, g and b values as ints which make them all look something like this:

0000 0000 0000 0000 0000 0000 0000 0000

With the last first (bits are read from right to left) 2 bytes (8 bits) actually representing the given colour value (0-255).

So to pack them all together into 1 int you need to combine the bits and shift the Red colour 2 bytes (16 bits) to the left and the Green byte 1 byte (8 bits) to the left using the universal bitwise or operator so that you get them in the nice RGB order.

Or you could simply create the java Colour object using the "Color(int, int, int)" contructor. and skip the whole bit combining business.

While there's also colorspace issues when interpolating colors, the problem our unvowelled monkey friend had was merely an arithmetic error. 

If you're not doing photo correction, HSV will probably be good enough.

I think I'd use one of the cheap uniform colorspaces...like whatever that integer-to-integer one used in H264 is or the old cinepak one for instance.