Qt3D: Scale entity size according to a distance between entity and camera

Question

It is easy to resize entity in a code:

self.transform = Qt3DCore.QTransform()
self.transform.setScale(1.5)

But I want to resize entity dynamically. I want that my entity enlarge when I move camera away from it or shrinks when I approach my camera. Is it possible to do this using proper shaders?

Answer 1

I found this link.

where is a code which I have added added to my vertex shader:

in vec3 vertexPosition;
uniform mat4 modelViewProjection;

void main()
{
    float reciprScaleOnscreen = 0.005;
    float w = (modelViewProjection * vec4(0.0, 0.0, 0.0, 1.0)).w;
    w *= reciprScaleOnscreen;

    gl_Position = modelViewProjection * vec4(vertexPosition.xyz * w , 1.0);
}

So there is no need to scale entities in a program. It is simpler to use a shader.