function Connection(config){ var self = this; // Properties self.from = config.from; self.to = config.to; self.uncuttable = config.uncuttable || false; self.sim = config.sim; // Sprite self.sprite = new Sprite({ src: "sprites/line.png", frames:1, sw:300, sh:20, }); self.sprite.pivotX = 2.8; self.sprite.pivotY = 10; // Update self.update = function(){}; // Draw self.draw = function(ctx){ var s = self.sim.options.scale || 1; ctx.save(); ctx.translate(self.from.x, self.from.y); var dx = self.to.x - self.from.x; var dy = self.to.y - self.from.y; var a = Math.atan2(dy,dx); var dist = Math.sqrt(dx*dx + dy*dy); self.sprite.scaleX = dist/300; self.sprite.scaleY = self.uncuttable ? 1 : 0.5; // thick=uncuttable //self.sprite.scaleY *= s; self.sprite.rotation = a; self.sprite.draw(ctx); ctx.restore(); }; // Hit Test with a LINE SEGMENT // code adapted from https://gist.github.com/Joncom/e8e8d18ebe7fe55c3894 self.hitTest = function(line){ var p0_x, p0_y, p1_x, p1_y, p2_x, p2_y, p3_x, p3_y; p0_x = line[0]; p0_y = line[1]; p1_x = line[2]; p1_y = line[3]; p2_x = self.from.x; p2_y = self.from.y; p3_x = self.to.x; p3_y = self.to.y; var s1_x, s1_y, s2_x, s2_y; s1_x = p1_x - p0_x; s1_y = p1_y - p0_y; s2_x = p3_x - p2_x; s2_y = p3_y - p2_y; var s, t; s = (-s1_y * (p0_x - p2_x) + s1_x * (p0_y - p2_y)) / (-s2_x * s1_y + s1_x * s2_y); t = ( s2_x * (p0_y - p2_y) - s2_y * (p0_x - p2_x)) / (-s2_x * s1_y + s1_x * s2_y); return (s >= 0 && s <= 1 && t >= 0 && t <= 1); }; }