public Shader getShader(AssetManager assetManager, EnumSet<Caps> rendererCaps, DefineList defines) {
          Shader shader = definesToShaderMap.get(defines);
          if (shader == null) {
              shader = loadShader(assetManager, rendererCaps, defines);
              definesToShaderMap.put(defines.deepClone(), shader);
          }
          return shader;
     }
Create a define list with the size matching the number
of defines on this technique.

@return a define list with the size matching the number
of defines on this technique.
jme3-core/src/main/java/com/jme3/material/TechniqueDef.java