com.grillecube.engine.opengl.object.GLProgram.java Source code

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Here is the source code for com.grillecube.engine.opengl.object.GLProgram.java

Source

/**
**   This file is part of the project https://github.com/toss-dev/VoxelEngine
**
**   License is available here: https://raw.githubusercontent.com/toss-dev/VoxelEngine/master/LICENSE.md
**
**   PEREIRA Romain
**                                       4-----7          
**                                      /|    /|
**                                     0-----3 |
**                                     | 5___|_6
**                                     |/    | /
**                                     1-----2
*/

package com.grillecube.engine.opengl.object;

import java.nio.FloatBuffer;
import java.util.ArrayList;

import org.lwjgl.BufferUtils;
import org.lwjgl.opengl.GL20;

import com.grillecube.engine.Logger;
import com.grillecube.engine.maths.Matrix4f;
import com.grillecube.engine.maths.Vector2f;
import com.grillecube.engine.maths.Vector3f;
import com.grillecube.engine.maths.Vector4f;
import com.grillecube.engine.opengl.GLH;

/**
 * How to use: 
 * Program p = new Program();
 * 
 * p.addShader(GLH.loadShader("..."));
 * p.link();
 * 
 * p.useStart();
 * render();
 * p.useStop();
 */

/** openGL program */
public abstract class GLProgram implements GLObject {
    private FloatBuffer _matrix_buffer;
    private ArrayList<GLShader> _shaders;
    private int _programID;

    /** standart program class with a vertex + fragment shader */
    public GLProgram() {
        this._matrix_buffer = BufferUtils.createFloatBuffer(4 * 4);
        this._shaders = new ArrayList<GLShader>();
    }

    public void addShader(GLShader shader) {
        this._shaders.add(shader);
    }

    public void link() {
        this._programID = GL20.glCreateProgram();
        for (GLShader shader : this._shaders) {
            GL20.glAttachShader(this._programID, shader.getID());
        }
        this.bindAttributes();
        GL20.glLinkProgram(this._programID);
        String message = GL20.glGetProgramInfoLog(this._programID);
        if (message.length() > 0) {
            Logger.get().log(Logger.Level.WARNING, "Linking shader message: " + message);
        }

        GL20.glValidateProgram(this._programID);

        this.linkUniforms();

        GLH.glhAddObject(this);
    }

    public abstract void bindAttributes();

    /** set every uniforms variables */
    public abstract void linkUniforms();

    /**
     * GLObject implementation, do not call it, this will be called
     * automatically when program exit
     */
    @Override
    public void delete() {
        GL20.glDeleteProgram(this._programID);
    }

    public void useStart() {
        GL20.glUseProgram(this._programID);
    }

    public void useStop() {
        GL20.glUseProgram(0);
    }

    protected void bindAttribute(int attribute, String name) {
        GL20.glBindAttribLocation(this._programID, attribute, name);
    }

    protected void loadUniformInteger(int location, int value) {
        GL20.glUniform1i(location, value);
    }

    protected void loadUniformFloat(int location, float value) {
        GL20.glUniform1f(location, value);
    }

    protected void loadUniformVec(int location, Vector2f vec) {
        GL20.glUniform2f(location, vec.x, vec.y);
    }

    protected void loadUniformVec(int location, Vector3f vec) {
        GL20.glUniform3f(location, vec.x, vec.y, vec.z);
    }

    protected void loadUniformVec(int location, Vector4f vec) {
        GL20.glUniform4f(location, vec.x, vec.y, vec.z, vec.w);
    }

    protected void loadUniformMatrix(int location, Matrix4f matrix) {
        matrix.store(_matrix_buffer);
        _matrix_buffer.flip();
        GL20.glUniformMatrix4fv(location, false, _matrix_buffer);
    }

    public int getUniform(String name) {
        return (GL20.glGetUniformLocation(this._programID, name));
    }
}