flash version here
// Covering the canvas ??
// set dimensions for new document
var w = 640; // units
var h = 480;
// instantiate raster canvas for use
var RC = new RasterCanvas(w, h, Units.PIXELS)
// set a color to use
RC.setPenColor(0, 0, 0);
// initialize variables
var opacity = .5;
var new_x = 0;
var new_y = 0;
var i = 0;
var dice3 = 0;
var a_x = 0;
var a_y = 0;
var b_x = 640;
var b_y = 0;
var c_x = 320;
var c_y = 480;
// roll the dice to decide which corner to go towards
while (i < 10000) {
dice3 = Math.random()
if ((dice3 > 0) && (dice3 < .333)) {
draw_midpoint(a_x, a_y, new_x, new_y);
}
if ((dice3 > .333) && (dice3 < .6666)) {
draw_midpoint(b_x, b_y, new_x, new_y)
}
if ((dice3 > .6666) && (dice3 < .9999)) {
draw_midpoint(c_x, c_y, new_x, new_y)
}
i++;
}
// release object referencess
RC = null;
// draw the midpoint between the old point and the corner
// make the new point the old point
function draw_midpoint(x1, y1, x2, y2) {
new_x =(x1 + x2) * .5
new_y =(y1 + y2) * .5
RC.setPixel(new_x, new_y, .4);
//C.drawLine(new_x, new_y, new_x+.001 , new_y+.001 )
//C.drawLine((1 - new_x), (1 - new_y), (1 - new_x+.001) , (1 - new_y+.001) )
}
// Utility Object ------------------------------------
// object definition
function RasterCanvas(w, h, units) {
// public properties
this.width = w;
this.height = h;
this.penColor;
this.penWeight = 1;
this.opacity = 1.0;
// public methods
this.getPixel = function(x, y, pixelColor) {
// works on current layer
// returns color under region(x, y, x+1, y+1)
// *very* slow ..faster for dark colors.. ;P
if (this.inRange(x, this.w) && this.inRange(y, this.h)) {
// set doc mode to rgb pixels
var origUnits = preferences.rulerUnits;
preferences.rulerUnits = Units.PIXELS;
var origMode = this.D.mode;
this.D.mode = DocumentMode.RGB;
// make a 1 pixel selection to limit scope of histogram
this.D.selection.select(new Array(new Array(x, y),
new Array(x+1, y),
new Array(x+1, y+1),
new Array(x, y+1)
), SelectionType.REPLACE);
// find where in histogram is the pixel color value, per channel
var C = new Array(0,0,0);
for (var i = 0; i < 3; i++) {
// only run thru histogram if value is hiding inside
if (eval(this.D.channels[i].histogram.join("+")) > 0) {
// locate position/value of pixel within [0,255]
for (var n=0; n==0&&C[i]<256; C[i]++) {
n = this.D.channels[i].histogram[C[i]];
}
C[i]--; // undo last increment
}
}
// set color components
pixelColor.rgb.green = C[0];
pixelColor.rgb.red = C[1];
pixelColor.rgb.blue = C[2];
this.D.selection.deselect();
// restore settings
this.D.mode = origMode;
preferences.rulerUnits = origUnits;
} else {
//this.err("setPixel", "some values out of range, please double-check.");
}
}
this.setPixel = function(x, y, opacity) {
// works on current layer
// fills 1 pixel selection of region(x, y, x+1, y+1)
// uses color object passed in at opacity specified [0,100]
// rather slow
if (this.inRange(x, this.w) && this.inRange(y, this.h)) {
this.D.selection.select(new Array(new Array(x, y),
new Array(x+1, y),
new Array(x+1, y+1),
new Array(x, y+1)
), SelectionType.REPLACE);
this.D.selection.fill(this.penColor, ColorBlendMode.NORMAL, opacity*100, false);
this.D.selection.deselect();
} else {
//this.err("setPixel", "some values out of range, please double-check.");
}
}
this.setBackgroundColor = function(normR, normG, normB) {
if (this.normalizedAll(new Array(normR, normG, normB))) {
var c = this.newRgbColor(255 * normR, 255 * normG, 255 * normB);
var r = this.newRectRegion(0, 0, this.w-1, this.h-1);
this.fillRegion(this.D, r, c, 100);
} else {
this.err("setBackgroundColor", "some values out of range, please double-check.");
}
};
this.setPenColor = function(normR, normG, normB) {
if (this.normalizedAll(new Array(normR, normG, normB))) {
this.penColor = this.newRgbColor(255 * normR, 255 * normG, 255 * normB);
} else {
this.err("setPenColor", "some values out of range, please double-check.");
}
};
this.setPenWeight = function(w) {
if (w > 0) {
this.penWeight = Math.max(w, 1);
} else {
this.err("setPenWeight", "value out of range, please double-check.");
}
};
this.setOpacity = function(normO) {
if (this.normalized(normO)) {
this.opacity = normO;
} else {
this.err("setOpacity", "value out of range, please double-check.");
}
};
this.drawLine = function(x1,y1, x2,y2) {
// pseudo draw a line by filling a selection that encompasses the end points
if (this.inRangeAll(new Array(x1, x2), this.w) && this.inRangeAll(new Array(y1, y2), this.h)) {
// set a 'thickness' for the line
var d = Math.max(this.penWeight, 2) * .5;
// declare some endpoint variables to set below
var p1, p2, p3, p4;
// lines of different orientations require different ordered selection points
if (x1 == x2) {
// vertical line
if (y1 < y2) {
p1 = new Array(x1-d, y1-d);
p2 = new Array(x1+d, y1-d);
p3 = new Array(x2+d, y2+d);
p4 = new Array(x2-d, y2+d);
} else {
p1 = new Array(x1-d, y1+d);
p2 = new Array(x1+d, y1+d);
p3 = new Array(x2+d, y2-d);
p4 = new Array(x2-d, y2-d);
}
} else if (y1 == y2) {
// horizontal line
if (x1 < x2) {
p1 = new Array(x1-d, y1-d);
p2 = new Array(x2+d, y1-d);
p3 = new Array(x2+d, y2+d);
p4 = new Array(x1-d, y2+d);
} else {
p1 = new Array(x1+d, y1-d);
p2 = new Array(x2-d, y1-d);
p3 = new Array(x2-d, y2+d);
p4 = new Array(x0+d, y2+d);
}
} else if ((x1 <= x2) && (y1 <= y2)) {
// slope down to right
p1 = new Array(x1-d, y1);
p2 = new Array(x1, y1-d);
p3 = new Array(x2+d, y2);
p4 = new Array(x2, y2+d);
} else if ((x1 > x2) && (y1 <= y2)) {
// slope down to left
p1 = new Array(x1+d, y1);
p2 = new Array(x1, y1-d);
p3 = new Array(x2-d, y2);
p4 = new Array(x2, y2+d);
} else if ((x1 <= x2) && (y1 > y2)) {
// slope up to right
p1 = new Array(x1-d, y1);
p2 = new Array(x1, y1+d);
p3 = new Array(x2+d, y2);
p4 = new Array(x2, y2-d);
} else { // ((x1 > x2) && (y1 > y2))
// slope up to left
p1 = new Array(x1+d, y1);
p2 = new Array(x1, y1+d);
p3 = new Array(x2-d, y2);
p4 = new Array(x2, y2-d);
}
var r = new Array(p1, p2, p3, p4);
this.fillRegion(this.D, r, this.penColor, this.opacity*100);
} else {
//this.err("drawLine", "some values out of range, please double-check.");
}
};
// private methods
this.err = function(label, msg) {
// pops up error message
alert("ERR " + label + "() : " + msg);
};
this.inRange = function(val, limit) {
// checks that value is in range [0,1]
var ans = true;
var v = parseFloat(val);
ans = ans && (v != Number.NaN);
if (ans) {
ans = ans && ((v >= 0) && (v <= limit));
}
return ans;
};
this.inRangeAll = function(valArray, limit) {
// checks validity of all values in array
var ans = true;
for (var i = 0; i < valArray.length; i++) {
ans = ans && this.inRange(valArray[i], limit);
}
return ans;
};
this.normalized = function(val) {
// checks that value is in range [0,1]
var ans = true;
var v = parseFloat(val);
ans = ans && (v != Number.NaN);
if (ans) {
ans = ans && ((v >= 0) && (v <= 1));
}
return ans;
};
this.normalizedAll = function(valArray) {
// checks validity of all values in array
var ans = true;
for (var i = 0; i < valArray.length; i++) {
ans = ans && this.normalized(valArray[i]);
}
return ans;
};
this.newDocument = function(width, height, unitType) {
// create and return new document of specified dimensions
// save original units setting
var origUnits = preferences.rulerUnits;
// set new units and create document with them
preferences.rulerUnits = unitType;
var D = documents.add(width, height);
// restore original units
preferences.rulerUnits = origUnits;
// return new document
return D;
};
this.newRgbColor = function(r, g, b) {
// returns SolidColor object set to rgb values given
var C = new SolidColor();
C.rgb.red = r;
C.rgb.green = g;
C.rgb.blue = b;
return C;
};
this.newRectRegion = function(L, T, R, B) {
// returns array of consecutive point arrays (a region)
// region can be specified CW or CCW
var TL = new Array(L, T);
var TR = new Array(R, T);
var BR = new Array(R, B);
var BL = new Array(L, B);
return new Array(TL, TR, BR, BL);
};
this.fillRegion = function(docRef, region, color, opacity) {
// works on current layer
// selects and fills region with color
docRef.selection.select(region, SelectionType.REPLACE);
docRef.selection.fill(color, ColorBlendMode.NORMAL, opacity*100, false);
docRef.selection.deselect();
};
// private properties
// need to occur after functions they call are defined
this.w = w;
this.h = w;
this.D = this.newDocument(w, h, units);
this.penColor = this.newRgbColor(0, 0, 0);
return this;
}