shadertest.java

// Create a new shader manager
ShaderManager shaderManager = new ShaderManager();

// Create shaders
BlurShader blurShader = new BlurShader();
CRTShader crtShader = new CRTShader();

// Add them to the manager in a layer-based way. At first, the blur shader is applied and so on.
shaderManager.add(this, blurShader, crtShader);


/* ... */

// In the resize method:

shaderManager.resize(width, height);

// In the render method:

shaderManager.updateAndRender(batch, delta);