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OpenGL Basic shader doesn't want to color the quad

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robee00    206

I'm started to learn LWJGL and OpenGL, and following a tutorial, my code doesn't want to color the quad.

[source lang="java"]public class Game{

private int vaoID = 0;
private int vboID = 0;
private int vboiID = 0; //for indices
private int vbocID = 0; //for colors
private int indicesCount = 0;

private int vsID = 0;
private int fsID = 0;
private int pID = 0;

public Game() {
Display.setDisplayMode(new DisplayMode(1280,720));
catch(LWJGLException e)

private void start()



private void init()
GL11.glClearColor(0.4f, 0.6f, 0.9f, 0f);

GL11.glViewport(0, 0, 1280, 720);

//Default is counter-clockwise!!!
//It's not important when using Elements!
float[] vertices = {

//OGL Buffers requires flipped byte buffers
FloatBuffer verticesBuffer = BufferUtils.createFloatBuffer(vertices.length);

float[] colors = {
FloatBuffer colorBuffer = BufferUtils.createFloatBuffer(colors.length);

byte[] indices = {
//Left bottom
0, 1, 2,
//Right top
2, 3, 0

indicesCount = indices.length;
ByteBuffer indicesBuffer = BufferUtils.createByteBuffer(indicesCount);

//Create new VAO, and bind the data
// A VAO can have up to 16 attributes (VBO's) assigned to it by default
vaoID = GL30.glGenVertexArrays();

//Create new VBO, and bind
// A VBO is a collection of Vectors which in this case resemble the location of each vertex.
vboID = GL15.glGenBuffers();
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vboID);
GL15.glBufferData(GL15.GL_ARRAY_BUFFER, verticesBuffer, GL15.GL_STATIC_DRAW);

//Put the VBO in the attrib list at index 0
GL20.glVertexAttribPointer(0, 4 ,GL11.GL_FLOAT, false, 0, 0);

//Deselect (bind to 0) the VBO
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);

//Create new VBO for colors
vbocID = GL15.glGenBuffers();
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vbocID);
GL15.glBufferData(GL15.GL_ARRAY_BUFFER, colorBuffer, GL15.GL_STATIC_DRAW);
GL20.glVertexAttribPointer(1, 4, GL11.GL_FLOAT, false, 0, 0);
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);

//Deselect (bind to 0) the VAO

//Create new VBO for indices, and bind it
vboiID = GL15.glGenBuffers();
GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, vboiID);
GL15.glBufferData(GL15.GL_ELEMENT_ARRAY_BUFFER, indicesBuffer, GL15.GL_STATIC_DRAW);
//Deselect it

//Load shaders
vsID = loadShader("src/net/doubler/hexdef/basic.vs", GL20.GL_VERTEX_SHADER);
fsID = loadShader("src/net/doubler/hexdef/basic.fs", GL20.GL_FRAGMENT_SHADER);

//Create program, and apply shaders
pID = GL20.glCreateProgram();
GL20.glAttachShader(pID, vsID);
GL20.glAttachShader(pID, fsID);

//Position info will be attrib 0
GL20.glBindAttribLocation(pID, 0, "in_Position");
//Color info will be attrib 1
GL20.glBindAttribLocation(pID, 1, "in_Color");

//Validate program

private void doMainLoop()


//Bind to the VAO that has all the info about the quad vertices

//Bind to the index VBO that has the info about the order
GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, vboiID);

//Draw the vertices
GL11.glDrawElements(GL11.GL_TRIANGLES, indicesCount, GL11.GL_UNSIGNED_BYTE, 0);

//Put everything back to default



private void cleanUp()
//clean up every trash

//Delete shaders
GL20.glDetachShader(pID, vsID);
GL20.glDetachShader(pID, fsID);


//Select VAO

//Disable the VBO index from the VAO attrib list

//Delete the vertex VBO
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);

//Delete the index VBO

//Delete the color VBO
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);

//Delete the VAO


public int loadShader(String name, int type)
StringBuilder source = new StringBuilder();
int shaderID = 0;

BufferedReader reader = new BufferedReader(new FileReader(name));
String line;
while((line = reader.readLine()) != null)

catch(IOException e)

shaderID = GL20.glCreateShader(type);
GL20.glShaderSource(shaderID, source);

return shaderID;

public static void main(String[] args) {
Game app = new Game();



[source lang="cpp"]#version 330

in vec4 in_Position;
in vec4 in_Color;

out vec4 pass_Color;

void main(void)
gl_Position = in_Position;
pass_Color = in_Color;

[source lang="cpp"]#version 330

in vec4 pass_Color;

out vec4 out_Color;

void main(void)
out_Color = pass_Color;

The only output I get is a white quad. It looks like the shaders are not compiling or I don't know. I tried to change out_Color to gl_FragColor, still white quad. Thanks in advance Edited by RobeeZ

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