Question

I’ve just started learning LWJGL (Java OpenGL), and i’m encountering an enormous amount of lag on my program.

Basically, I’m trying to make a 2.5D Minecraft clone, so what I’ve done for the world code is create a multidimensional array of the “Block” class i made Its 150 By 50 . Here’s the code for my world class so far:

And here is my render loop:

Some extra info, all the draw method for the “Block” class does is draw all the sides of a cube, except for the back.

So, what is happening is that it is rendering a big wall of cubes (What i wanted), except that the FPS is VERY bad.

I’m not quite sure what I’m doing wrong. And remember that I need an array of cubes because since it’s going to be like Minecraft, i’m going to have to be able to easily organize the blocks, and be able to destroy/place blocks depending on what the user does.

Thanks!

Edit: Draw Method For The Block Class:

    Texture stone = Util.createTexture("Tiles/Stone.png");

    stone.bind();
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

    glBegin(GL_QUADS);
        //FRONT FACE
        glTexCoord3f(0,1,z);
        glVertex3f(x,y,z);

        glTexCoord3f(1,1,z);
        glVertex3f(x + width,y,z);

        glTexCoord3f(1,0,z);
        glVertex3f(x + width,y + height,z);

        glTexCoord3f(0,0,z);
        glVertex3f(x,y + height, z);

        //RIGHT FACE
        glTexCoord3f(0,1,z);
        glVertex3f(x + width,y,z);

        glTexCoord3f(1,1,z - length);
        glVertex3f(x + width,y,z - length);

        glTexCoord3f(1,0,z - length);
        glVertex3f(x + width,y + height,z - length);

        glTexCoord3f(0,0,z);
        glVertex3f(x + width,y + height,z);
        //LEFT FACE
        glTexCoord3f(0,1,z);
        glVertex3f(x,y,z);

        glTexCoord3f(1,1,z - length);
        glVertex3f(x,y,z - length);

        glTexCoord3f(1,0,z - length);
        glVertex3f(x,y + height,z - length);

        glTexCoord3f(0,0,z);
        glVertex3f(x,y + height,z);

        //TOP FACE
        glTexCoord3f(0,1,z - length);
        glVertex3f(x,y + height,z - length);

        glTexCoord3f(1,1,z - length);
        glVertex3f(x + width,y + height,z - length);

        glTexCoord3f(1,0,z);
        glVertex3f(x + width,y + height,z);

        glTexCoord3f(0,0,z);
        glVertex3f(x,y + height,z);

        //BOTTOM FACE
        glTexCoord3f(0,1,z - length);
        glVertex3f(x,y,z - length);

        glTexCoord3f(1,1,z - length);
        glVertex3f(x + width,y,z - length);

        glTexCoord3f(1,0,z);
        glVertex3f(x + width,y,z);

        glTexCoord3f(0,0,z);
        glVertex3f(x,y,z);
    glEnd();

Answer 1

You shouldn’t create the texture every time block.draw() is called. Call it once, before you do any rendering.

Texture stone = Util.createTexture("Tiles/Stone.png");

It would also improve your performance to use vertex arrays instead of immediate mode drawing.