Changing the color of multiple images in one canvas

Question

I figured it out how to change my canvas's color but I have a problem when I put more than one image in my canvas it doesn't appear. I have just one image that appears. Here is the code.

This is when I load my images in 'canvas1'

var image01 = new Image();
var image02 = new Image();
var image03 = new Image();

image01.onload = function() {
    drawImage(this, 73, 32, 249.1, 390);
    changeColor(this, 0, 0, 165, 73, 32, 249.1, 390);

    image02.onload = function() {
        drawImage(this, 1, 64, 90, 335);
        changeColor(this, 0, 0, 165, 1, 64, 90, 335);
    }
    image02.src = "images/Manches/Longue/Slim/Homme/7C5D5D2D.png";

    image03.onload = function() {
        drawImage(this, 303, 65, 90, 335);
        changeColor(this, 0, 0, 165, 303, 65, 90, 335);
    }
    image03.src = "images/Manches/Longue/Slim/Homme/7C5D5D2E.png";
};
image01.src = "images/VueDevant/Homme/Droite/658FFBC6.png";

This is the function for changing the color of my canvas
(code adapted from an answer posted by K3N):

function changeColor(img, hue, sat, l, x, y, width, height) {

    context.clearRect(x, y, width, height);
    context.globalCompositeOperation = "source-over";
    context.drawImage(img, x, y, width, height);


    var lcombo = false;
    if (lcombo) {
        context.globalCompositeOperation = "color";
        context.fillStyle = "hsl(" + hue + "," + sat + "%, 50%)";
        context.fillRect(x, y, width, height);
        context.clearRect(x, y, width, height);
    } else {
        // adjust "lightness"
        context.globalCompositeOperation = l < 100 ? "color-burn" : "color-dodge";
        // for common slider, to produce a valid value for both directions
        l = l >= 100 ? l - 100 : 100 - (100 - l);
        context.fillStyle = "hsl(0, 50%, " + l + "%)";
        context.fillRect(x, y, width, height);
        // context.clearRect(x,y, width, height);

        // adjust saturation
        context.globalCompositeOperation = "saturation";
        context.fillStyle = "hsl(0," + sat + "%, 50%)";
        context.fillRect(x, y, width, height);
        // context.clearRect(x,y, width, height);

        // adjust hue
        context.globalCompositeOperation = "hue"; //hue
        context.fillStyle = "hsl(" + hue + ",1%, 50%)";
        // context.fillRect(x, y, width,height);
    }
    // clip
    context.globalCompositeOperation = "destination-in";
    context.drawImage(img, x, y, width, height);
    context.globalCompositeOperation = "source-over";

}

score 0 · Answer 1 · answered Aug 03 '17 at 12:20

Because I'm not fimilar with Canvas objects and an incomplete code example from questioner, I created my own example. After that I ran step by step through each line and created so a running example:

<html>
 <body>
  <canvas id="myCanvas" width="700" height="700" style="border: 1px solid red;"></canvas>
  <script type="text/javascript">
   var canvas = document.getElementById('myCanvas'),
   context = canvas.getContext('2d');

   var image01 = new Image();
   var image02 = new Image();
   var image03 = new Image();

   image01.onload = function()
   {
    changeColor(image01, 0, 0, 165, 73, 32, 249.1, 390);

    image02.onload = function() {
     changeColor(image02, 0, 0, 165, 1, 64, 90, 335);
    }
    image02.src = "https://1.f.ix.de/scale/geometry/360x202/q75/imgs/09/2/2/5/1/1/9/7/zeroday-d774e8c5b2414e48-b0237d756e9017a9-39b755ca2936afda.jpeg";

    image03.onload = function() {
     changeColor(image03, 0, 0, 565, 303, 65, 90, 335);
    }
    image03.src = "https://1.f.ix.de/scale/geometry/696/q75/imgs/18/2/2/5/2/1/4/1/autofly-010b77473b49efc6.jpeg";
   };
   image01.src = "https://1.f.ix.de/scale/geometry/336/q75/imgs/18/2/2/5/2/1/4/1/image-1499148077454426-aa28a644b6934a51.jpeg";
   function changeColor(img, hue, sat, l, x, y, width, height)
   {
    context.clearRect(x, y, width, height);
    context.globalCompositeOperation = "source-over";
    context.drawImage(img, x, y, width, height);

    var lcombo = false;
    if (lcombo) {
     context.globalCompositeOperation = "color";
     context.fillStyle = "hsl(" + hue + "," + sat + "%, 50%)";
     context.fillRect(x, y, width, height);
     context.clearRect(x, y, width, height);
    } else {
     context.globalCompositeOperation = l < 100 ? "color-burn" : "color-dodge";
     l = l >= 100 ? l - 100 : 100 - (100 - l);
     context.fillStyle = "hsl(0, 50%, " + l + "%)";

     context.globalCompositeOperation = "saturation";
     context.fillStyle = "hsl(0," + sat + "%, 50%)";
     context.fillRect(x, y, width, height);

     context.globalCompositeOperation = "hue"; //hue
     context.fillStyle = "hsl(" + hue + ",1%, 50%)";
    }
    context.globalCompositeOperation = "destination-in";
    context.globalCompositeOperation = "source-over";
   }
  </script>
 </body>
</html>

In my eyes the mistake was in the last three lines in function changeColor():

context.globalCompositeOperation = "destination-in";
context.drawImage(img, x, y, width, height);
context.globalCompositeOperation = "source-over";

After I deleted the line context.drawImage(img, x, y, width, height);, all three pictures are visible (see my example).

Thank you for your answer but I have gray rectangles under my images I need to remove those rectangles ...here is the link of the result https://ibb.co/jt2GGa — yasmina jaaouane, Aug 03 '17 at 13:06
@yasminajaaouane This requirement is/was not part of your question. — Reporter, Aug 03 '17 at 13:25
According https://www.w3schools.com/colors/colors_hsl.asp it could be an issue of Saturation because, 0% of this attribute means an image gets a shade of grey. — Reporter, Aug 03 '17 at 13:32

Changing the color of multiple images in one canvas

1 Answers1