最贊回答 / x米多米拉
改成下面這樣了，不知道還有沒有問題，歡迎交流~var blurR = 50; for(var i = 0; i < canvasA.height; i++){ ????for(var j = 0; j < canvasA.width; j++ ){ ????????var r = 0,g = 0,b = 0,totalNum = 0; ????????for(var m = -blurR; m <= blurR; m++){ ??...
2018-08-08
i j 直接從0開始遍歷，當blurR半徑比較大的時候，越界的像素點用另一邊的像素點補充，邊緣就可以模糊一些了，雖然效率有點慢，哈哈哈，四層循環里面判斷下x y的值就可以了
for(let k = 0; k < blurR; k++){
if( x < 0){
x += canvasb.height;
}else if(x > canvasb.height - 1){
x -= canvasb.height; }
if( y < 0){
y += canvasb.width;
}else if(y > canvasb.width - 1){
y -= canvasb.width;}
}
for(let k = 0; k < blurR; k++){
if( x < 0){
x += canvasb.height;
}else if(x > canvasb.height - 1){
x -= canvasb.height; }
if( y < 0){
y += canvasb.width;
}else if(y > canvasb.width - 1){
y -= canvasb.width;}
}
2018-04-03
第一個：
var imageWidth = canvas.width * scale；
var imageHeight = canvas.height * scale；
var x = (imageWidth - canvas.width) / (2*scale);
var y = (imageHeight - canvas.height)/ (2*scale);
context.drawImage( image , x , y , canvas.width/scale , canvas.height/scale , 0 , 0 , canvas.width , canvas.height )
var imageWidth = canvas.width * scale；
var imageHeight = canvas.height * scale；
var x = (imageWidth - canvas.width) / (2*scale);
var y = (imageHeight - canvas.height)/ (2*scale);
context.drawImage( image , x , y , canvas.width/scale , canvas.height/scale , 0 , 0 , canvas.width , canvas.height )
2018-03-19
第一種方法，只是假想擴大了，其實并沒有，所以最后的坐標跟長寬還要改回去，應該是
context.drawImage( image , sx/scale , sy/scale , canvas.width/scale , canvas.height/scale , 0 , 0 , canvas.width , canvas.height )
context.drawImage( image , sx/scale , sy/scale , canvas.width/scale , canvas.height/scale , 0 , 0 , canvas.width , canvas.height )
2018-03-19
var mousedown = false
slider.onmousedown = function () {
mousedown = true
}
slider.onmouseup = function () {
mousedown = false
}
slider.onmousemove = function () {
if (mousedown) {
scale = this.value
drawImageByScale(scale)
}
}
slider.onmousedown = function () {
mousedown = true
}
slider.onmouseup = function () {
mousedown = false
}
slider.onmousemove = function () {
if (mousedown) {
scale = this.value
drawImageByScale(scale)
}
}
2018-02-02
溫馨提示：img-lg這個圖片本來是大的，繪制到canvas上的時候縮小了，使用放大鏡繪制的時候，直接使用了這個圖片，都是據此計算的
2018-01-11
