Method _copyHelper

src/image/p5.Image.js:918–970

(
    dstImage,
    srcImage,
    sx,
    sy,
    sw,
    sh,
    dx,
    dy,
    dw,
    dh
  )

  }

  _copyHelper(
    dstImage,
    srcImage,
    sx,
    sy,
    sw,
    sh,
    dx,
    dy,
    dw,
    dh
  ){
    const s = srcImage.canvas.width / srcImage.width;
    // adjust coord system for 3D when renderer
    // ie top-left = -width/2, -height/2
    let sxMod = 0;
    let syMod = 0;
    if (srcImage._renderer && srcImage._renderer.isP3D) {
      sxMod = srcImage.width / 2;
      syMod = srcImage.height / 2;
    }
    if (dstImage._renderer && dstImage._renderer.isP3D) {
      dstImage.push();
      dstImage.resetMatrix();
      dstImage.noLights();
      dstImage.blendMode(dstImage.BLEND);
      dstImage.imageMode(dstImage.CORNER);
      dstImage._renderer.image(
        srcImage,
        sx + sxMod,
        sy + syMod,
        sw,
        sh,
        dx,
        dy,
        dw,
        dh
      );
      dstImage.pop();
    } else {
      dstImage.drawingContext.drawImage(
        srcImage.canvas,
        s * (sx + sxMod),
        s * (sy + syMod),
        s * sw,
        s * sh,
        dx,
        dy,
        dw,
        dh
      );
    }
  }

  /**
   * Masks part of the image with another.