java - How many shaders should i use? -

i've written own 3d game engine in java want rewrite optimization.

my engine looks this:

there abstract superclass called rendersystem. code :

public abstract class rendersystem<t> {     public abstract void addelement(t element);     public abstract void enablesystem();     public abstract void disablesystem();     protected abstract void cleanup(); } 

every rendersystem extends "rendersystem". every different material there render system , therefore shader. i've created enum stores parts of material enabled (bump_map, displacement_map etc.)

it looks this: (i missed out getter , setter stuff) code :

public enum materialtype{  color_mat (1,false,false,false,false,masterrenderer.entity_system,null);  private materialtype(int index, boolean use_bump_map, boolean use_displacement_map, boolean use_normal_map,         boolean use_specular_map, rendersystem<?> default_system, rendersystem<?> instanced_system) {     this.index = index;     this.use_bump_map = use_bump_map;     this.use_displacement_map = use_displacement_map;     this.use_normal_map = use_normal_map;     this.use_specular_map = use_specular_map;     this.default_system = default_system;     this.instanced_system = instanced_system; }  private final int index; private final boolean use_bump_map; private final boolean use_displacement_map; private final boolean use_normal_map; private final boolean use_specular_map;  private final rendersystem<?> default_system; private final rendersystem<?> instanced_system;    //................... 

in example, stored 1 material in it, not use of maps except color_map (which enabled). furthermore, stores systems deals kinds of entities use material. code : masterrenderer.entity_system

this done else, add skydome material, particle material etc. straight forward question is, shaders need ?

shall write 1 shader every entity, (entities created using obj. file, no particles etc. included) or 1 shader normal rendering without bump_maps , stuff, , 1 shader material normal_map ? mean render every entity 1 shader, if not have of maps has calculate stuff.

furthermore want add bonesystem characters. guess that's should have own shader ? below list shaders create:

• entityshader (only colormap)
• entityshader (colormap , normalmap)
• entityshader (colormap , specularmap)
• entityshader (colormap, normalmap , specularmap)
• entityshader (colormap, bumpmap, displacementmap, normalmap, specularmap)
• charactershader (only colormap bones)
• skydomeshader (only colormap), renders sky
• particleshader (probably colormap instanced!!)
• terrainshader (probably own material stuff blending)
• shadowshader (takes entities , no other map, renders depth framebuffer)
• watershader (if bored , have nothing else do)
• and finally: instancedentityshader (only colormap instanced)

i might add postprocessing effects that's not safe yet.

i want know if structure okay , effective or should change anything?

also, how many shaders used in games?