add FrameBuffer Object

src/globalgamejam/render/FrameBufferObject.java

@@ -0,0 +1,110 @@
+package globalgamejam.render;
+
+import static org.lwjgl.opengl.GL11.*;
+import static org.lwjgl.opengl.GL30.*;
+import static org.lwjgl.opengl.GL32.*;
+
+import globalgamejam.Main;
+import globalgamejam.math.Matrix4f;
+import globalgamejam.math.Vector2f;
+import org.lwjgl.BufferUtils;
+import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL13;
+import org.lwjgl.opengl.GL15;
+import org.lwjgl.opengl.GL20;
+
+import java.nio.FloatBuffer;
+import java.nio.IntBuffer;
+
+/**
+ * Created by MrDev023 on 14/01/2017.
+ */
+public class FrameBufferObject {
+
+    private int fbo,fboTexID,renderID,vbo,size;
+
+    public FrameBufferObject(){
+        int width = Main.WIDTH;
+        int height = Main.HEIGHT;
+        this.fbo = glGenFramebuffers();
+        glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+
+        //Creation de la texture qui va contenir la sortie RGB du shader
+        int renderedTexture = glGenTextures();
+        glBindTexture(GL_TEXTURE_2D, renderedTexture);
+        glTexImage2D(GL_TEXTURE_2D, 0,GL_RGB, width, height, 0,GL_RGB, GL_UNSIGNED_BYTE, 0);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+
+        //Creation du tampon de profondeur
+        int depthrenderbuffer = glGenRenderbuffers();
+        glBindRenderbuffer(GL_RENDERBUFFER, depthrenderbuffer);
+        glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, width, height);
+        glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depthrenderbuffer);
+
+        //Definir le render Texture
+        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,GL_TEXTURE_2D, renderedTexture, 0);
+        IntBuffer drawBuffs = BufferUtils.createIntBuffer(1);
+        drawBuffs.put(0, GL_COLOR_ATTACHMENT0);
+        GL20.glDrawBuffers(drawBuffs);
+        if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
+            throw new IllegalStateException("FBO not loaded !");
+        fboTexID = renderedTexture;
+        renderID = depthrenderbuffer;
+
+
+        this.vbo = GL15.glGenBuffers();
+        float[] a = new float[]{
+                0,0,        0.0f,0.0f,
+                1,0,         1.0f,0.0f,
+                1,1,          1.0f,1.0f,
+                0,1,         0.0f,1.0f
+        };
+        FloatBuffer buffer = BufferUtils.createFloatBuffer(a.length);
+        buffer.put(a).flip();
+        size = a.length/(2+2);
+
+        GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vbo);
+        GL15.glBufferData(GL15.GL_ARRAY_BUFFER, buffer, GL15.GL_STATIC_DRAW);
+
+        GL20.glEnableVertexAttribArray(Shaders.MAIN_SHADERS.getAttribLocation("vert"));
+        GL20.glVertexAttribPointer(Shaders.MAIN_SHADERS.getAttribLocation("vert"), 2, GL11.GL_FLOAT, false, (2+2)*4, 0);
+
+        GL20.glEnableVertexAttribArray(Shaders.MAIN_SHADERS.getAttribLocation("vertTexCoord"));
+        GL20.glVertexAttribPointer(Shaders.MAIN_SHADERS.getAttribLocation("vertTexCoord"), 2, GL11.GL_FLOAT, true, (2+2)*4, 2*4);
+
+        GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
+    }
+
+    public void startRenderToFBO(){
+        glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+        glViewport(0,0,Main.WIDTH,Main.HEIGHT);
+    }
+
+    public void stopRenderToFBO(){
+        glBindFramebuffer(GL_FRAMEBUFFER, 0);
+    }
+
+    public void renderFBO(){
+
+        glBindFramebuffer(GL_FRAMEBUFFER, 0);
+        glViewport(0,0,Main.WIDTH,Main.HEIGHT);
+
+        Shaders.MAIN_FBO.bind();
+        Shaders.MAIN_FBO.uniform("projection", (new Matrix4f()).Ortho2D(0,1,0,1,-1,1).mul(new Matrix4f().translate(.5f,.5f,0)));
+        GL13.glActiveTexture(GL13.GL_TEXTURE0);
+        glBindTexture(GL_TEXTURE_2D, fboTexID);
+        GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vbo);
+        GL11.glDrawArrays(GL11.GL_QUADS, 0, size);
+        GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
+        glBindTexture(GL_TEXTURE_2D, 0);
+        Shaders.MAIN_SHADERS.unbind();
+    }
+
+    public void destroy(){
+        glDeleteTextures(fboTexID);
+        glDeleteRenderbuffers(renderID);
+        glDeleteFramebuffers(fbo);
+    }
+
+}

src/globalgamejam/render/Shaders.java

@@ -12,11 +12,12 @@ public class Shaders {
 	
 	public int program;
 
-	public static Shaders MAIN_SHADERS;
+	public static Shaders MAIN_SHADERS,MAIN_FBO;
 
 	static{
 		try{
 			MAIN_SHADERS = new Shaders("res/shaders/main.vert","res/shaders/main.frag");
+			MAIN_FBO = new Shaders("res/shaders/fbo.vert","res/shaders/fbo.frag");
 		}catch(Exception e){
 			e.printStackTrace();
 		}