Posted by Chaz on Feb 22, 2015; 2:45pm
URL: https://forum.jogamp.org/How-to-add-colors-or-normals-to-custom-object-tp4034048.html

Yo. I have next task: load heightmap and visualize it like a 3D object. Actually I already did it using simple GL_ARRAY_BUFFER and DrawArrays.
But my image totally has not any normals, or seems that all normals are the same. (Lighting is enabled).
I tried example where was used glVertexAttribPointer, but i got fatal error when try assign color's data.
Here is my 3 main functions.

 public void CreateBuffer(GL2 gl) // creating buffers with vertex and color data
    {
        this.gl=gl;
        targetsBuffer = Buffers.newDirectIntBuffer(2);
        gl.glGenBuffers(2, targetsBuffer);

        gl.glBindBuffer(GL.GL_ARRAY_BUFFER, targetsBuffer.get(0));
        gl.glBufferData(GL.GL_ARRAY_BUFFER, fBuff.capacity() * Buffers.SIZEOF_FLOAT, fBuff, GL.GL_STATIC_DRAW);

        gl.glBindBuffer(GL.GL_ARRAY_BUFFER, targetsBuffer.get(1));
        gl.glBufferData(GL.GL_ARRAY_BUFFER, cBuff.capacity() * Buffers.SIZEOF_FLOAT, cBuff, GL.GL_STATIC_DRAW); // here I got exception (fatal error)

        CreateVAO();
    }

    public void CreateVAO() // creating something that should help me to colorize my object
    {
        IntBuffer id = Buffers.newDirectIntBuffer(1);
        gl.glGenVertexArrays(1,id);

        gl.glBindVertexArray(id.get(0));
        gl.glBindBuffer(GL2.GL_ARRAY_BUFFER, targetsBuffer.get(0));
        gl.glVertexAttribPointer(0, 3, GL2.GL_FLOAT,false,0,0);

        gl.glBindBuffer(GL2.GL_ARRAY_BUFFER,targetsBuffer.get(1));
        gl.glVertexAttribPointer(1, 3, GL2.GL_FLOAT,false,0,0);

    }

    @Override
    public void Draw(){
        gl.glEnableVertexAttribArray(0);
        gl.glEnableVertexAttribArray(1);

        gl.glBindVertexArray(0);

        gl.glDrawArrays(GL2.GL_QUADS, 0, fBuff.capacity() / 3);

        gl.glDisableVertexAttribArray(0);
        gl.glDisableVertexAttribArray(1);
    }

So what I do wrong?

UPD: Actually I understood where is was 1 of my faults - i have to call rewind() for cBuff. And I had change Draw function to this
 public void Draw(){
        gl.glBindVertexArray(1);

        gl.glEnableVertexAttribArray(0);
        gl.glEnableVertexAttribArray(1);

        gl.glDrawArrays(GL2.GL_QUADS, 0, fBuff.capacity() / 3);

        gl.glDisableVertexAttribArray(0);
        gl.glDisableVertexAttribArray(1);
    }

Now I don't got exceptions, but I still don't see colors on my object. Here is function in which I initialize and filling the buffers.

 private void Import(String path) throws Exception
    {
        byte[] bytes = Files.readAllBytes(Paths.get(path));
        int resolution = (int)Math.sqrt(bytes.length/4);
        float[] floats=new float[resolution*resolution];
        ByteBuffer.wrap(bytes).order(ByteOrder.nativeOrder()).asFloatBuffer().get(floats);

        this.heightStickLength=this.widthStickLength=resolution;
        this.heightScale=1;

        minHeight=Float.MAX_VALUE;
        maxHeight = Float.MIN_VALUE;

        for(int i = 0; i<floats.length; i++)
        {
            floats[i]=floats[i]*600f;
        }

        for(float f : floats)
        {
            if(f>maxHeight) maxHeight=f;
            if(f<minHeight) minHeight=f;
        }

        CreateColliderShape(floats);

        System.out.println("Max height: "+maxHeight+" Min height: "+minHeight);

        float step = 2000/513f;
        float optiStep=1;

        fBuff = Buffers.newDirectFloatBuffer(resolution*resolution*3*4/(int)optiStep);
        cBuff = Buffers.newDirectFloatBuffer(resolution*resolution*3*4/(int)optiStep);

        for(int i =0; i<resolution-1; i+=optiStep)
        {
            for(int j =0; j<resolution-1; j+=optiStep)
            {
                float x1=i*step,y1=floats[(j)*resolution+(resolution-1-i)],z1=j*step;

                float x2=i*step+step,y2=floats[(j)*resolution+(resolution-2-i)],z2=j*step;

                float x3=i*step+step,y3=floats[(j+1)*resolution+(resolution-2-i)],z3=j*step+step;

                float x4=i*step,y4=floats[(j+1)*resolution+(resolution-1-i)],z4=j*step+step;

                    fBuff.put(x1); cBuff.put(1);
                    fBuff.put(y1); cBuff.put(0);
                    fBuff.put(z1); cBuff.put(0);

                    fBuff.put(x2); cBuff.put(1);
                    fBuff.put(y2); cBuff.put(0);
                    fBuff.put(z2); cBuff.put(0);

                    fBuff.put(x3); cBuff.put(1);
                    fBuff.put(y3); cBuff.put(0);
                    fBuff.put(z3); cBuff.put(0);

                    fBuff.put(x4); cBuff.put(1);
                    fBuff.put(y4); cBuff.put(0);
                    fBuff.put(z4); cBuff.put(0);
            }
        }

        fBuff.rewind();
        cBuff.rewind();
    }