Adjusting Orthographic Camera in Three.js

When using an OrthographicCamera in Three.js, the perspective distortion you're describing (left side appearing smaller than right side) is unusual since orthographic cameras don't create perspective distortion by design. However, there are several approaches you can take to adjust your setup to make the left side appear larger:

1. Adjust Camera Position and Rotation

You can reposition your camera to change the viewing angle:

JAVASCRIPTCopied
// Move camera more to the right side
camera.position.x = somePositiveValue;
// Rotate camera to look toward the left side
camera.lookAt(new THREE.Vector3(-someValue, 0, 0));

2. Modify Orthographic Camera Parameters

You can adjust the frustum parameters of your orthographic camera:

JAVASCRIPTCopied
// Create an asymmetric frustum with more space on the left
const camera = new THREE.OrthographicCamera(
  -rightBound * 1.5, // Extend left boundary (negative value)
  rightBound,        // Normal right boundary
  topBound,          // Normal top boundary
  -topBound,         // Normal bottom boundary
  nearClip,
  farClip
);

3. Apply Scale Transformation to Your Model

Another approach is to scale your model asymmetrically:

JAVASCRIPTCopied
// Create a scale matrix that enlarges the left side
const modelObject = new THREE.Object3D();
modelObject.add(yourModel);
// Apply non-uniform scaling
modelObject.scale.set(1.5, 1, 1);
// Position to compensate for the scaling
modelObject.position.x = someOffsetValue;

4. Use a Custom Shader

For more precise control, you could implement a custom shader that applies non-uniform scaling to specific parts of your model.

Remember that orthographic cameras should display objects at the same size regardless of distance, so if you're seeing perspective-like effects, it might be worth checking if your camera is truly set up as orthographic and not accidentally using a PerspectiveCamera.