You can run the filter multiple times with different center coordinates.
Copy code
- import processing.opengl.*;
- import codeanticode.glgraphics.*;
- int lensDiam = 400;
- float magFactor = 5, scalef = .3f;
- GLTexture textImage, lensImage;
- GLTextureFilter lensFilter;
- void setup() {
- size(450, 450, GLConstants.GLGRAPHICS);
- noFill();
- ellipseMode(CORNERS);
- textureMode(NORMAL);
- textImage = new GLTexture(this, "text.png");
- lensImage = new GLTexture(this, textImage.width, textImage.height);
- lensFilter = new GLTextureFilter(this, "Mask.xml");
- }
- void draw() {
- if (mouseX <= 0) mouseX = width/2;
- if (mouseY <= 0) mouseY = height/2;
-
- float x0 = constrain(mouseX, 90, width - 90);
- float y0 = constrain(mouseY, 90, height - 90);
-
- // display the original picture
- image(textImage, 0, 0, width, height);
- // Draw lenses.
- createLensImage(x0, y0);
- createLensImage(y0, x0);
- }
- void createLensImage(float x0, float y0) {
- int radius = lensDiam/2;
- float radiusAdj = radius/magFactor;
- float lensDiamAdj = (int)(lensDiam/magFactor);
-
- float x = (x0 - radiusAdj);
- float y = (y0 - radiusAdj);
-
- // Converting magnified area to normalized texture coordinates:
- float u0 = constrain(x / width, 0, 1);
- float v0 = constrain(y / height, 0, 1);
- float u1 = constrain(u0 + lensDiamAdj / width, 0, 1);
- float v1 = constrain(v0 + lensDiamAdj / height, 0, 1);
-
- // Making pixels transparent outside the lens area.
- lensFilter.setParameterValue("center", new float[]{(u0 + u1)/2, (v0 + v1) / 2});
- lensFilter.setParameterValue("radius", (float)radiusAdj/(width));
- lensFilter.apply(textImage, lensImage);
-
- // display magnified image
- noStroke();
- pushMatrix();
- translate(x0 - (radius*scalef), y0 - (radius*scalef));
- scale(scalef);
- beginShape(QUADS);
- texture(lensImage);
- vertex(0, 0, u0, v0);
- vertex(lensDiam, 0, u1, v0);
- vertex(lensDiam, lensDiam, u1, v1);
- vertex(0, lensDiam, u0, v1);
- endShape();
-
- // drawing lens border.
- stroke(0);
- noFill();
- ellipse(0, 0, lensDiam,lensDiam);
- popMatrix();
- }
