kubex.gui.Hud.java Source code

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Here is the source code for kubex.gui.Hud.java

Source

package kubex.gui;

import static org.lwjgl.opengl.GL11.GL_TRIANGLES;
import static org.lwjgl.opengl.GL11.glDrawArrays;
import static org.lwjgl.opengl.GL11.glEnable;
import static org.lwjgl.opengl.GL11.glDisable;
import static org.lwjgl.opengl.GL15.glBindBuffer;
import static org.lwjgl.opengl.GL15.glBufferData;
import static org.lwjgl.opengl.GL15.glBufferSubData;
import static org.lwjgl.opengl.GL15.glGenBuffers;

import java.nio.FloatBuffer;

import org.lwjgl.opengl.GL11;
import org.lwjgl.opengl.GL15;

import kubex.shaders.HudShaderProgram;
import kubex.storage.FloatBufferPool;

/**
 * This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
 * 
 * @author Vctor Arellano Vicente (Ivelate)
 * 
 * Hud class. Prints the gray dot of the center of the screen
 */
public class Hud {
    private static final float CURSOR_SIZE = 4;
    private static final float CURSOR_ALPHA = 0.5f;
    private static final float CURSOR_R = 1;
    private static final float CURSOR_G = 1;
    private static final float CURSOR_B = 1;
    private static final int CURSOR_VERT_NUM = 8; //Uses 8 vertexes for the circle

    private HudShaderProgram HSP;

    private int vbo;
    private int currentVert;

    public Hud(HudShaderProgram hsp, int xres, int yres) {
        this.HSP = hsp;
        this.vbo = glGenBuffers();
        glBindBuffer(GL15.GL_ARRAY_BUFFER, this.vbo);

        HSP.enable();
        HSP.setupAttributes();
        FloatBuffer toUpload = FloatBufferPool.getBuffer();
        float normx = CURSOR_SIZE / xres;
        float normy = CURSOR_SIZE / yres;

        float[] list = new float[CURSOR_VERT_NUM * 3 * 6];
        insertCircle(0, 0, normx, normy, CURSOR_VERT_NUM, CURSOR_R, CURSOR_G, CURSOR_B, CURSOR_ALPHA, list);

        toUpload.put(list);
        toUpload.flip();
        glBufferData(GL15.GL_ARRAY_BUFFER, (list.length * 4) + (36 * 4), GL15.GL_STATIC_DRAW);
        glBufferSubData(GL15.GL_ARRAY_BUFFER, 0, toUpload);
        glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
        FloatBufferPool.recycleBuffer(toUpload);
        this.currentVert = CURSOR_VERT_NUM * 3;
    }

    /**
     * Insert the circle vertexes defined by the method arguments in the float list <list>
     */
    private void insertCircle(float ix, float iy, float radx, float rady, int vert, float c_r, float c_g, float c_b,
            float c_a, float[] list) {
        float lastx = radx + ix;
        float lasty = iy;
        for (int i = 1; i <= vert; i++) {
            double angle = 2 * Math.PI * i / vert;
            float x = (float) ((Math.cos(angle) * radx) + ix);
            float y = (float) ((Math.sin(angle) * rady) + iy);
            int cont = (i - 1) * 3 * 6;
            list[cont] = ix;
            list[cont + 1] = iy;
            list[cont + 2] = c_r;
            list[cont + 3] = c_g;
            list[cont + 4] = c_b;
            list[cont + 5] = c_a;
            list[cont + 6] = lastx;
            list[cont + 7] = lasty;
            list[cont + 8] = c_r;
            list[cont + 9] = c_g;
            list[cont + 10] = c_b;
            list[cont + 11] = c_a;
            list[cont + 12] = x;
            list[cont + 13] = y;
            list[cont + 14] = c_r;
            list[cont + 15] = c_g;
            list[cont + 16] = c_b;
            list[cont + 17] = c_a;
            lastx = x;
            lasty = y;
        }
    }

    /**
     * Draws the circle
     */
    public void draw() {
        glEnable(GL11.GL_BLEND);
        glDisable(GL11.GL_DEPTH_TEST);
        glBindBuffer(GL15.GL_ARRAY_BUFFER, this.vbo);
        HSP.setupAttributes();
        glDrawArrays(GL_TRIANGLES, 0, currentVert);
        glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
    }
}