ofxColorGradient

added in this fork:

// draw orientation (default is horizontal)
gradient.setDrawVertical(true);

// draw gradient direction (invert default direction)
gradient.setDrawDirFlip(true);

Simple OpenFrameworks addon to create linear color gradients

ofxColorGradient<ofColor> gradient;

//first, fill in the gradient with colors, left to right
gradient.addColor( ofColor::red );
gradient.addColor( ofColor::green );
gradient.addColor( ofColor::yellow );

//query the gradient for a color at a specific spot
ofColor color = gradient.getColorAtPercent(0.2);

//rinse and repeat to draw the full gradient
for(float i = 0.0f; i < 1.0f; i+= 0.1f){
	ofSetColor( gradient.getColorAtPercent(i) );
	//draw using that color
}

It also allows creating a gradient from an image.

It also provides Google's Turbo Rainbow Colormap, which comes with an Apache-2.0 license.

License

ofxColorGradient is made available under the MIT license.

It includes Google's Turbo Rainbow Colormap, which uses the Apache-2.0 license.