virtual void onDraw(Graphics& g, const Viewpoint& v){
if(updateScene){
// pick new swatches
// clear polygons and re-seed random number generator
verts.reset();
rng.seed(rnd::seed());
float variedParam1, variedParam2, fixedParam1, fixedParam2;
RGB swatch;
float width = 1.0f / numCols / 2;
float height = 1.0f / numRows / 2;
float widthOffset = width / 2.0f;
float heightOffset = height / 2.0f;
if(MODE > 2){
//randomly select two of the three parameters
//these will stay constant across the whole
//grid for modes 3 - 6
fixedParam1 = rng.uniform();
fixedParam2 = rng.uniform();
}
// Create grid
for(int i=1; i<=numCols*2; i+=2){
//NOTE: uniform distribution produces reliable gradients
// but is more likely to produce duplicates.
// deviating from uniform distribution produces fewer
// duplicate gradients but exposes holes in gamut
if(MODE < 3){
//randomly select two of the three parameters
//these will change for each gradient for modes 3 -6
fixedParam1 = rng.uniform();
fixedParam2 = rng.uniform();
}
//print header for rgb values
cout << "Column " << i/2 + 1 << ":" << endl;
for(int j=1; j<=numRows*2; j+=2){
//linearly interpolate two of the three parameters
//(only one will be used for modes 1 - 3)
variedParam1 = (float)j/(numRows*2);
variedParam2 = (float)i/(numCols*2);
//choose gradient type based on current mode
switch(MODE){
case VARYING_HUE:
swatch = (TYPE == HCLAB)?RGB(HCLab(variedParam1, fixedParam1, fixedParam2)):
RGB(HCLuv(variedParam1, fixedParam1, fixedParam2));
break;
case VARYING_CHROMA:
swatch = (TYPE == HCLAB)?RGB(HCLab(fixedParam1, variedParam1, fixedParam2)):
RGB(HCLuv(fixedParam1, variedParam1, fixedParam2));
break;
case VARYING_LUMINANCE:
swatch = (TYPE == HCLAB)?RGB(HCLab(fixedParam1, fixedParam2, variedParam1)):
RGB(HCLuv(fixedParam1, fixedParam2, variedParam1));
break;
case FIXED_HUE:
swatch = (TYPE == HCLAB)?RGB(HCLab(fixedParam1, variedParam2, variedParam1)):
RGB(HCLuv(fixedParam1, variedParam2, variedParam1));
break;
case FIXED_CHROMA:
swatch = (TYPE == HCLAB)?RGB(HCLab(variedParam2, fixedParam1, variedParam1)):
RGB(HCLuv(variedParam2, fixedParam1, variedParam1));
break;
case FIXED_LUMINANCE:
swatch = (TYPE == HCLAB)?RGB(HCLab(variedParam2, variedParam1, fixedParam1)):
RGB(HCLuv(variedParam2, variedParam1, fixedParam1));
break;
}
//draw rectangles
verts.vertex(i*width - widthOffset, j*height - heightOffset); //bottom left
verts.color(swatch);
verts.vertex(i*width + width - widthOffset, j*height- heightOffset); //bottom right
verts.color(swatch);
verts.vertex(i*width + width - widthOffset, j*height + height - heightOffset); //top right
verts.color(swatch);
verts.vertex(i*width - widthOffset, j*height + height - heightOffset); //top left
verts.color(swatch);
//print RGB values [0, 255] for each swatch
cout << "{" << (int)(swatch.r * 255) << ", " << (int)(swatch.g * 255) << ", " << (int)(swatch.b * 255) << "}" << endl;
}
cout << endl;
}
//reset flag
updateScene = false;
//print instructions again for convenience
printInstructions();
}
// Switch to the projection matrix
g.pushMatrix(Graphics::PROJECTION);
// Set up 2D orthographic projection coordinates
// The args are left, right, bottom, top
g.loadMatrix(Matrix4f::ortho2D(0, 1, 0,1));
// Switch to the modelview matrix
g.pushMatrix(Graphics::MODELVIEW);
g.loadIdentity();
g.draw(verts);
g.popMatrix();
// Don't forget to restore original projection matrix
g.popMatrix(Graphics::PROJECTION);
}
