156 lines
5.5 KiB
HTML
156 lines
5.5 KiB
HTML
|
<!DOCTYPE html>
|
||
|
|
<html>
|
||
|
|
<head>
|
||
|
|
<title>Pixel Battle</title>
|
||
|
|
<meta charset="UTF-8">
|
||
|
|
|
||
|
|
</head>
|
||
|
|
<body>
|
||
|
|
<canvas id="board" width="1920" height="1080" style="border:1px solid #000000;" display="block">
|
||
|
|
<canvas hidden id="hidden" width="1920" height="1080" style="border:1px solid #000000;" display="block">
|
||
|
|
|
||
|
|
</canvas>
|
||
|
|
<script>
|
||
|
|
var canvas = document.getElementById("board");
|
||
|
|
var canvasHidden = document.getElementById("hidden");
|
||
|
|
var ctx = canvas.getContext("2d");
|
||
|
|
var ctx2 = canvasHidden.getContext("2d");
|
||
|
|
canvas.width = 1920;
|
||
|
|
canvas.height = 1080;
|
||
|
|
var imgData = ctx2.createImageData(canvasHidden.width, canvasHidden.height)
|
||
|
|
|
||
|
|
// All the code that is making zooms and moving around cavnas is made with big help of http://phrogz.net/tmp/canvas_zoom_to_cursor.html. Thanks alot!
|
||
|
|
window.onload = function() {
|
||
|
|
var ctx = canvas.getContext("2d");
|
||
|
|
trackTransforms(ctx);
|
||
|
|
function redraw(x ,y) {
|
||
|
|
ctx.save();
|
||
|
|
ctx.setTransform(1,0,0,1,0,0);
|
||
|
|
ctx.clearRect(0,0,canvas.width,canvas.height);
|
||
|
|
ctx.restore();
|
||
|
|
for (let i = 0; i < 1000; i += 4) {
|
||
|
|
imgData.data[i+0] = 255;
|
||
|
|
imgData.data[i+1] = 0;
|
||
|
|
imgData.data[i+2] = 0;
|
||
|
|
imgData.data[i+3] = 255;
|
||
|
|
}
|
||
|
|
ctx2.putImageData(imgData, 10, 50);
|
||
|
|
ctx.drawImage(canvasHidden, 0, 0)
|
||
|
|
}
|
||
|
|
|
||
|
|
function drawPixel(x, y, color) {
|
||
|
|
let pixelNumber = y * canvas.width + x // THIS IS NOT CORRECT. MUST BE FIXED
|
||
|
|
for (let i = 0; i < 4; i ++)
|
||
|
|
imgData.data[pixelNumber+i] = color[i]
|
||
|
|
redraw();
|
||
|
|
}
|
||
|
|
|
||
|
|
redraw();
|
||
|
|
|
||
|
|
var lastX=canvas.width/2, lastY=canvas.height/2;
|
||
|
|
var dragStart,dragged;
|
||
|
|
canvas.addEventListener('mousedown',function(evt){
|
||
|
|
document.body.style.mozUserSelect = document.body.style.webkitUserSelect = document.body.style.userSelect = 'none';
|
||
|
|
lastX = evt.offsetX || (evt.pageX - canvas.offsetLeft);
|
||
|
|
lastY = evt.offsetY || (evt.pageY - canvas.offsetTop);
|
||
|
|
dragStart = ctx.transformedPoint(lastX,lastY);
|
||
|
|
dragged = false;
|
||
|
|
|
||
|
|
},false);
|
||
|
|
canvas.addEventListener('mousemove',function(evt){
|
||
|
|
lastX = evt.offsetX || (evt.pageX - canvas.offsetLeft);
|
||
|
|
lastY = evt.offsetY || (evt.pageY - canvas.offsetTop);
|
||
|
|
dragged = true;
|
||
|
|
if (dragStart){
|
||
|
|
var pt = ctx.transformedPoint(lastX,lastY);
|
||
|
|
ctx.translate(pt.x-dragStart.x,pt.y-dragStart.y);
|
||
|
|
redraw();
|
||
|
|
}
|
||
|
|
},false);
|
||
|
|
canvas.addEventListener('mouseup',function(evt){
|
||
|
|
dragStart = null;
|
||
|
|
|
||
|
|
if (!dragged) drawPixel(
|
||
|
|
Math.round(ctx.transformedPoint(lastX,lastY).x),
|
||
|
|
Math.round(ctx.transformedPoint(lastX,lastY).y)
|
||
|
|
)
|
||
|
|
// if (!dragged) zoom(evt.shiftKey ? -1 : 1 );
|
||
|
|
},false);
|
||
|
|
|
||
|
|
var scaleFactor = 1.1;
|
||
|
|
var zoom = function(clicks){
|
||
|
|
var pt = ctx.transformedPoint(lastX,lastY);
|
||
|
|
ctx.translate(pt.x,pt.y);
|
||
|
|
var factor = Math.pow(scaleFactor,clicks);
|
||
|
|
ctx.scale(factor,factor);
|
||
|
|
ctx.translate(-pt.x,-pt.y);
|
||
|
|
redraw();
|
||
|
|
}
|
||
|
|
|
||
|
|
var handleScroll = function(evt){
|
||
|
|
var delta = evt.wheelDelta ? evt.wheelDelta/40 : evt.detail ? -evt.detail : 0;
|
||
|
|
if (delta) zoom(delta);
|
||
|
|
return evt.preventDefault() && false;
|
||
|
|
};
|
||
|
|
canvas.addEventListener('DOMMouseScroll',handleScroll,false);
|
||
|
|
canvas.addEventListener('mousewheel',handleScroll,false);
|
||
|
|
};
|
||
|
|
|
||
|
|
function trackTransforms(ctx){
|
||
|
|
var svg = document.createElementNS("http://www.w3.org/2000/svg",'svg');
|
||
|
|
var xform = svg.createSVGMatrix();
|
||
|
|
ctx.getTransform = function(){ return xform; };
|
||
|
|
|
||
|
|
var savedTransforms = [];
|
||
|
|
var save = ctx.save;
|
||
|
|
ctx.save = function(){
|
||
|
|
savedTransforms.push(xform.translate(0,0));
|
||
|
|
return save.call(ctx);
|
||
|
|
};
|
||
|
|
var restore = ctx.restore;
|
||
|
|
ctx.restore = function(){
|
||
|
|
xform = savedTransforms.pop();
|
||
|
|
return restore.call(ctx);
|
||
|
|
};
|
||
|
|
|
||
|
|
var scale = ctx.scale;
|
||
|
|
ctx.scale = function(sx,sy){
|
||
|
|
xform = xform.scaleNonUniform(sx,sy);
|
||
|
|
return scale.call(ctx,sx,sy);
|
||
|
|
};
|
||
|
|
var rotate = ctx.rotate;
|
||
|
|
ctx.rotate = function(radians){
|
||
|
|
xform = xform.rotate(radians*180/Math.PI);
|
||
|
|
return rotate.call(ctx,radians);
|
||
|
|
};
|
||
|
|
var translate = ctx.translate;
|
||
|
|
ctx.translate = function(dx,dy){
|
||
|
|
xform = xform.translate(dx,dy);
|
||
|
|
return translate.call(ctx,dx,dy);
|
||
|
|
};
|
||
|
|
var transform = ctx.transform;
|
||
|
|
ctx.transform = function(a,b,c,d,e,f){
|
||
|
|
var m2 = svg.createSVGMatrix();
|
||
|
|
m2.a=a; m2.b=b; m2.c=c; m2.d=d; m2.e=e; m2.f=f;
|
||
|
|
xform = xform.multiply(m2);
|
||
|
|
return transform.call(ctx,a,b,c,d,e,f);
|
||
|
|
};
|
||
|
|
var setTransform = ctx.setTransform;
|
||
|
|
ctx.setTransform = function(a,b,c,d,e,f){
|
||
|
|
xform.a = a;
|
||
|
|
xform.b = b;
|
||
|
|
xform.c = c;
|
||
|
|
xform.d = d;
|
||
|
|
xform.e = e;
|
||
|
|
xform.f = f;
|
||
|
|
return setTransform.call(ctx,a,b,c,d,e,f);
|
||
|
|
};
|
||
|
|
var pt = svg.createSVGPoint();
|
||
|
|
ctx.transformedPoint = function(x,y){
|
||
|
|
pt.x=x; pt.y=y;
|
||
|
|
return pt.matrixTransform(xform.inverse());
|
||
|
|
}
|
||
|
|
}
|
||
|
|
</script>
|
||
|
|
</body>
|
||
|
|
</html>
|