更新

Question

我要执行的操作：在画布上绘制图像（png），然后将该画布重新绘制/复制到另一个画布上。

在哪里工作：如果我在画布上绘制图像（png），然后只显示原始画布。它显示正常，包括随机矩形：

var canvas = document.createElement('canvas');
var ctx = canvas.getContext("2d");
var image = new Image();
image.src ="./path/image.png";

image.onload = function(){
    ctx.drawImage(image,tempCanvas.width/2,tempCanvas.height/2); 
}

ctx.fillRect(tempCanvas.width/2,tempCanvas.height/2,20,20); //random rectangle that also displays correctly

document.getElementById("placeholder2").appendChild(canvas);

失败的地方：如果我在画布上绘制图像（png），然后尝试将原始画布和图像一起绘制到另一画布上，则尽管随机矩形也被绘制，但该图像不会显示到临时画布的显示效果很好：

var canvas = document.createElement('canvas');
var ctx = canvas.getContext("2d");

var tempCanvas = document.createElement('canvas'); //temp canvas
var tCTX = tempCanvas.getContext("2d");
tempCanvas.width = canvas.width;

var image = new Image();
image.src ="./path/image.png";

image.onload = function(){
    tCTX.drawImage(image,tempCanvas.width/2,tempCanvas.height/2); //Draw the image to a temp canvas this time first
}

tCTX.fillRect(tempCanvas.width/2,tempCanvas.height/2,20,20); //Random rectangle also gets drawn to the temp canvas

ctx.drawImage(tempCanvas,canvas.width/2 - tempCanvas.width/2,canvas.height/2 - tempCanvas.height/2); //Now try and draw the temp canvas to the original canvas

document.getElementById("placeholder2").appendChild(canvas);

不确定我是在做蠢事还是遇到某种限制？任何帮助表示赞赏！

Answer 1

您的问题是：在tempCanvas上绘制图像时，是从画布的中心绘制的。这样，将仅在图像tempCanvas的右下角绘制图像的前四分之一，然后从该图像的中心在tempCanvas上绘制canvas。您的图像已绘制，但绘制在canvas之外。请尝试以下方法：

var canvas = document.createElement('canvas');
//wrap.appendChild(canvas);
canvas.width = 300;
canvas.height= 300;
var ctx = canvas.getContext("2d");

var tempCanvas = document.createElement('canvas'); 
//wrap.appendChild(tempCanvas);//temp canvas
var tCTX = tempCanvas.getContext("2d");
tempCanvas.width = canvas.width;
tempCanvas.height = canvas.height;

var image = new Image();
image.src = d.src;

image.onload = function(){
    tCTX.drawImage(image,0,0); //Draw the image to a temp canvas this time first


tCTX.fillRect(tempCanvas.width/2,tempCanvas.height/2,20,20); //Random rectangle also gets drawn to the temp canvas

ctx.drawImage(tempCanvas,0,0); //Now try and draw the temp canvas to the original canvas
}
document.getElementById("placeholder2").appendChild(canvas);

更新

OP正在评论：您好，Enxaneta，谢谢您的建议！试试看，仍然不能正常工作。因此，我决定添加一个有效的示例：

var canvas = document.createElement('canvas');
//wrap.appendChild(canvas);
canvas.width = 300;
canvas.height= 300;
var ctx = canvas.getContext("2d");

var tempCanvas = document.createElement('canvas'); 
//wrap.appendChild(tempCanvas);//temp canvas
var tCTX = tempCanvas.getContext("2d");
tempCanvas.width = canvas.width;
tempCanvas.height = canvas.height;

var image = new Image();
image.src = d.src;

image.onload = function(){
    tCTX.drawImage(image,0,0); //Draw the image to a temp canvas this time first


tCTX.fillRect(tempCanvas.width/2,tempCanvas.height/2,20,20); //Random rectangle also gets drawn to the temp canvas

ctx.drawImage(tempCanvas,0,0); //Now try and draw the temp canvas to the original canvas
}
document.getElementById("placeholder2").appendChild(canvas);

<div id="placeholder2">
<img id="d" 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" />

将画布（包括图像）复制到另一个画布失败

1 个答案:

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