ronin/scripts/modules/filter.js
2016-11-18 00:51:44 -04:00

122 lines
3.5 KiB
JavaScript

function Filter(element)
{
Module.call(this);
this.parameters = [Text,Value];
this.active = function(cmd)
{
if(cmd.content.length < 1){ return; }
var p = cmd.content;
var filter_name = p[0];
p.shift();
switch(filter_name) {
case "saturation":
this.filter_saturation(this.pixels(),p);
break;
case "chromatic":
this.filter_chromatic(this.pixels(),p);
break;
}
}
this.passive = function(cmd)
{
}
// Filters
this.filter_saturation = function(pixels = this.pixels(),p = null)
{
var d = pixels.data;
for (var i=0; i<d.length; i+=4) {
var r = d[i];
var g = d[i+1];
var b = d[i+2];
// CIE luminance for the RGB
// The human eye is bad at seeing red and blue, so we de-emphasize them.
var v = 0.2126*r + 0.7152*g + 0.0722*b;
d[i] = d[i+1] = d[i+2] = v
}
ronin.canvas.clear();
ronin.canvas.context().putImageData(pixels, 0, 0, 0, 0, pixels.width, pixels.height);
}
this.filter_chromatic = function(pixels = this.pixels(),p = null)
{
var s;
if(p.length == 0)
s = {r:2,g:2,b:2};
else if(p.length < 3)
s = {r:parseFloat(p[0]), g:parseFloat(p[0])*.5, b:0};
else
s = {r:parseFloat(p[0]), g:parseFloat(p[1]), b:parseFloat(p[2])};
var hw = pixels.width*.5;
var hh = pixels.height*.5;
var maxLength = Math.sqrt(hw*hw+hh*hh);
var output = new ImageData(pixels.width, pixels.height);
for (var i=0; i<pixels.width; i++) {
for(var j=0; j<pixels.height; j++){
var x = i-hw;
var y = j-hh;
var a = Math.atan2(y,x);
var d = Math.sqrt(x*x+y*y);
var f = (d-s.r*d/maxLength);
x = Math.cos(a)*f+hw;
y = Math.sin(a)*f+hh;
var r = this.get_color_bilinear(pixels, x, y);
f = (d-s.g*d/maxLength);
x = Math.cos(a)*f+hw;
y = Math.sin(a)*f+hh;
var g = this.get_color_bilinear(pixels, x, y);
f = (d-s.b*d/maxLength);
x = Math.cos(a)*f+hw;
y = Math.sin(a)*f+hh;
var b = this.get_color_bilinear(pixels, x, y);
var c = {r:r.r, g:g.g, b:b.b,a:Math.max(r.a, Math.max(g.a,b.a))};
this.set_color(output, c, i,j);
}
}
ronin.canvas.clear();
ronin.canvas.context().putImageData(output, 0, 0, 0, 0, pixels.width, pixels.height);
}
this.set_color = function(pixels, color, x, y){
x = Math.max(0,Math.min(x,pixels.width-1));
y = Math.max(0,Math.min(y,pixels.height-1));
var index = (x+y*pixels.width)*4;
pixels.data[index] = color.r;
pixels.data[index+1] = color.g;
pixels.data[index+2] = color.b;
pixels.data[index+3] = color.a;
}
this.get_color = function(pixels,x,y){
x = Math.max(0,Math.min(x,pixels.width-1));
y = Math.max(0,Math.min(y,pixels.height-1));
var index = (x+y*pixels.width)*4;
return {r:pixels.data[index], g:pixels.data[index+1], b:pixels.data[index+2], a:pixels.data[index+3]};
}
this.get_color_bilinear = function(pixels, x, y){
var c1 = this.get_color(pixels, Math.floor(x),Math.floor(y));
var c2 = this.get_color(pixels, Math.ceil(x),Math.floor(y));
var c3 = this.get_color(pixels, Math.floor(x),Math.ceil(y));
var c4 = this.get_color(pixels, Math.ceil(x),Math.ceil(y));
return this.lerp_color(this.lerp_color(c1,c2, x%1),this.lerp_color(c3,c4, x%1), y%1);
}
this.lerp_color = function(c1, c2, t){
return {r:c1.r+t*(c2.r-c1.r), g:c1.g+t*(c2.g-c1.g), b:c1.b+t*(c2.b-c1.b), a:c1.a+t*(c2.a-c1.a)};
}
//
this.pixels = function()
{
return ronin.canvas.context().getImageData(0,0,ronin.canvas.element.width,ronin.canvas.element.height);
}
}