ababilinski / unity-gpu-texture-resize

A method that allows for fast GPU resizing in the Unity Engine.

Why This Script Was Created

This class allows you to resize an image on the GPU.

Speeds

Methods	Speeds	Source
ResizeTool.Resize(..)	00:00:40.89	This Tool [FREE]
UnityEngine.Texture2D.Resize(..)	01:08:08.55	Unity Method
ResizePro.Resize(..)	00:00:40.28	ResizePro [PAID ASSET]

Here is the process:

1. RenderTexture rt = RenderTexture.GetTemporary() create a temporary render texture with the target size
2. RenderTexture.active set the active RenderTexture to the temporary texture so we can read from it
3. Graphics.Blit() Copies source texture into destination render texture with a shader (on the gpu) more info
4. texture2D.Resize() resize the texture to the target values (this sets the pixel data as undefined) more info
5. texture2D.ReadPixels() reads the pixel values from the temporary RenderTexture onto the resized texture more info
6. texture2D.Apply() actually upload the changed pixels to the graphics card more info