pixel-editor/js/_changeZoom.js
2020-07-21 22:30:46 +02:00

32 lines
1.1 KiB
JavaScript

function changeZoom (layer, direction, cursorLocation) {
var oldWidth = canvasSize[0] * zoom;
var oldHeight = canvasSize[1] * zoom;
var newWidth, newHeight;
//change zoom level
//if you want to zoom out, and the zoom isnt already at the smallest level
if (direction == 'out' && zoom > 1) {
zoom -= Math.ceil(zoom / 10);
newWidth = canvasSize[0] * zoom;
newHeight = canvasSize[1] * zoom;
//adjust canvas position
layer.setCanvasOffset(layer.canvas.offsetLeft + (oldWidth - newWidth) *cursorLocation[0]/oldWidth, layer.canvas.offsetTop + (oldHeight - newHeight) *cursorLocation[1]/oldWidth);
}
//if you want to zoom in
else if (direction == 'in' && zoom + Math.ceil(zoom/10) < window.innerHeight/4){
zoom += Math.ceil(zoom/10);
newWidth = canvasSize[0] * zoom;
newHeight = canvasSize[1] * zoom;
//adjust canvas position
layer.setCanvasOffset(layer.canvas.offsetLeft - Math.round((newWidth - oldWidth)*cursorLocation[0]/oldWidth), layer.canvas.offsetTop - Math.round((newHeight - oldHeight)*cursorLocation[1]/oldHeight));
}
//resize canvas
layer.resize();
// adjust brush size
currentTool.updateCursor();
}