1. A concise explanation of the problem you're experiencing.
When using minimumPixelSize the update() function of Model takes significantly more processing power. I would like this to be faster.
My current workaround is only setting the minimum pixel size when the distance from the camera to the model is below a specific distance. This is handled by a encapsulated update() function.
2. A minimal code example. If you've found a bug, this helps us reproduce and repair it.
I think this is caused by the following code in the update function. modelTransformChanged is always true if the pixel size is != 128:
// Model's model matrix needs to be updated
var modelTransformChanged = !Matrix4.equals(this._modelMatrix, modelMatrix) ||
(this._scale !== this.scale) ||
(this._minimumPixelSize !== this.minimumPixelSize) || (this.minimumPixelSize !== 0.0) || // Minimum pixel size changed or is enabled
(this._maximumScale !== this.maximumScale) ||
(this._heightReference !== this.heightReference) || this._heightChanged ||
3. Context. Why do you need to do this? We might know a better way to accomplish your goal.
We visualize hundreds of models which need to have a Minimum Pixel size of 128.
4. The Cesium version you're using, your operating system and browser.