ClippingHelperImplementation.java

package net.minecraft.src;
// Decompiled by Jad v1.5.8g. Copyright 2001 Pavel Kouznetsov.
// Jad home page: http://www.kpdus.com/jad.html
// Decompiler options: packimports(3) braces deadcode 

import java.nio.Buffer;
import java.nio.FloatBuffer;
import org.lwjgl.opengl.GL11;

public class ClippingHelperImplementation extends ClippingHelper
{

    public ClippingHelperImplementation()
    {
        projectionMatrixBuffer = GLAllocation.createDirectFloatBuffer(16);
        modelviewMatrixBuffer = GLAllocation.createDirectFloatBuffer(16);
        unusedFloatBuffer = GLAllocation.createDirectFloatBuffer(16);
    }

    public static ClippingHelper getInstance()
    {
        instance.init();
        return instance;
    }

    private void normalize(float af[][], int i)
    {
        float f = MathHelper.sqrt_float(af[i][0] * af[i][0] + af[i][1] * af[i][1] + af[i][2] * af[i][2]);
        af[i][0] /= f;
        af[i][1] /= f;
        af[i][2] /= f;
        af[i][3] /= f;
    }

    private void init()
    {
        projectionMatrixBuffer.clear();
        modelviewMatrixBuffer.clear();
        unusedFloatBuffer.clear();
        GL11.glGetFloat(2983 /*GL_PROJECTION_MATRIX*/, projectionMatrixBuffer);
        GL11.glGetFloat(2982 /*GL_MODELVIEW_MATRIX*/, modelviewMatrixBuffer);
        projectionMatrixBuffer.flip().limit(16);
        projectionMatrixBuffer.get(projectionMatrix);
        modelviewMatrixBuffer.flip().limit(16);
        modelviewMatrixBuffer.get(modelviewMatrix);
        clippingMatrix[0] = modelviewMatrix[0] * projectionMatrix[0] + modelviewMatrix[1] * projectionMatrix[4] + modelviewMatrix[2] * projectionMatrix[8] + modelviewMatrix[3] * projectionMatrix[12];
        clippingMatrix[1] = modelviewMatrix[0] * projectionMatrix[1] + modelviewMatrix[1] * projectionMatrix[5] + modelviewMatrix[2] * projectionMatrix[9] + modelviewMatrix[3] * projectionMatrix[13];
        clippingMatrix[2] = modelviewMatrix[0] * projectionMatrix[2] + modelviewMatrix[1] * projectionMatrix[6] + modelviewMatrix[2] * projectionMatrix[10] + modelviewMatrix[3] * projectionMatrix[14];
        clippingMatrix[3] = modelviewMatrix[0] * projectionMatrix[3] + modelviewMatrix[1] * projectionMatrix[7] + modelviewMatrix[2] * projectionMatrix[11] + modelviewMatrix[3] * projectionMatrix[15];
        clippingMatrix[4] = modelviewMatrix[4] * projectionMatrix[0] + modelviewMatrix[5] * projectionMatrix[4] + modelviewMatrix[6] * projectionMatrix[8] + modelviewMatrix[7] * projectionMatrix[12];
        clippingMatrix[5] = modelviewMatrix[4] * projectionMatrix[1] + modelviewMatrix[5] * projectionMatrix[5] + modelviewMatrix[6] * projectionMatrix[9] + modelviewMatrix[7] * projectionMatrix[13];
        clippingMatrix[6] = modelviewMatrix[4] * projectionMatrix[2] + modelviewMatrix[5] * projectionMatrix[6] + modelviewMatrix[6] * projectionMatrix[10] + modelviewMatrix[7] * projectionMatrix[14];
        clippingMatrix[7] = modelviewMatrix[4] * projectionMatrix[3] + modelviewMatrix[5] * projectionMatrix[7] + modelviewMatrix[6] * projectionMatrix[11] + modelviewMatrix[7] * projectionMatrix[15];
        clippingMatrix[8] = modelviewMatrix[8] * projectionMatrix[0] + modelviewMatrix[9] * projectionMatrix[4] + modelviewMatrix[10] * projectionMatrix[8] + modelviewMatrix[11] * projectionMatrix[12];
        clippingMatrix[9] = modelviewMatrix[8] * projectionMatrix[1] + modelviewMatrix[9] * projectionMatrix[5] + modelviewMatrix[10] * projectionMatrix[9] + modelviewMatrix[11] * projectionMatrix[13];
        clippingMatrix[10] = modelviewMatrix[8] * projectionMatrix[2] + modelviewMatrix[9] * projectionMatrix[6] + modelviewMatrix[10] * projectionMatrix[10] + modelviewMatrix[11] * projectionMatrix[14];
        clippingMatrix[11] = modelviewMatrix[8] * projectionMatrix[3] + modelviewMatrix[9] * projectionMatrix[7] + modelviewMatrix[10] * projectionMatrix[11] + modelviewMatrix[11] * projectionMatrix[15];
        clippingMatrix[12] = modelviewMatrix[12] * projectionMatrix[0] + modelviewMatrix[13] * projectionMatrix[4] + modelviewMatrix[14] * projectionMatrix[8] + modelviewMatrix[15] * projectionMatrix[12];
        clippingMatrix[13] = modelviewMatrix[12] * projectionMatrix[1] + modelviewMatrix[13] * projectionMatrix[5] + modelviewMatrix[14] * projectionMatrix[9] + modelviewMatrix[15] * projectionMatrix[13];
        clippingMatrix[14] = modelviewMatrix[12] * projectionMatrix[2] + modelviewMatrix[13] * projectionMatrix[6] + modelviewMatrix[14] * projectionMatrix[10] + modelviewMatrix[15] * projectionMatrix[14];
        clippingMatrix[15] = modelviewMatrix[12] * projectionMatrix[3] + modelviewMatrix[13] * projectionMatrix[7] + modelviewMatrix[14] * projectionMatrix[11] + modelviewMatrix[15] * projectionMatrix[15];
        frustum[0][0] = clippingMatrix[3] - clippingMatrix[0];
        frustum[0][1] = clippingMatrix[7] - clippingMatrix[4];
        frustum[0][2] = clippingMatrix[11] - clippingMatrix[8];
        frustum[0][3] = clippingMatrix[15] - clippingMatrix[12];
        normalize(frustum, 0);
        frustum[1][0] = clippingMatrix[3] + clippingMatrix[0];
        frustum[1][1] = clippingMatrix[7] + clippingMatrix[4];
        frustum[1][2] = clippingMatrix[11] + clippingMatrix[8];
        frustum[1][3] = clippingMatrix[15] + clippingMatrix[12];
        normalize(frustum, 1);
        frustum[2][0] = clippingMatrix[3] + clippingMatrix[1];
        frustum[2][1] = clippingMatrix[7] + clippingMatrix[5];
        frustum[2][2] = clippingMatrix[11] + clippingMatrix[9];
        frustum[2][3] = clippingMatrix[15] + clippingMatrix[13];
        normalize(frustum, 2);
        frustum[3][0] = clippingMatrix[3] - clippingMatrix[1];
        frustum[3][1] = clippingMatrix[7] - clippingMatrix[5];
        frustum[3][2] = clippingMatrix[11] - clippingMatrix[9];
        frustum[3][3] = clippingMatrix[15] - clippingMatrix[13];
        normalize(frustum, 3);
        frustum[4][0] = clippingMatrix[3] - clippingMatrix[2];
        frustum[4][1] = clippingMatrix[7] - clippingMatrix[6];
        frustum[4][2] = clippingMatrix[11] - clippingMatrix[10];
        frustum[4][3] = clippingMatrix[15] - clippingMatrix[14];
        normalize(frustum, 4);
        frustum[5][0] = clippingMatrix[3] + clippingMatrix[2];
        frustum[5][1] = clippingMatrix[7] + clippingMatrix[6];
        frustum[5][2] = clippingMatrix[11] + clippingMatrix[10];
        frustum[5][3] = clippingMatrix[15] + clippingMatrix[14];
        normalize(frustum, 5);
    }

    private static ClippingHelperImplementation instance = new ClippingHelperImplementation();
    private FloatBuffer projectionMatrixBuffer;
    private FloatBuffer modelviewMatrixBuffer;
    private FloatBuffer unusedFloatBuffer;

}