org.jtrfp.mtmx.draw.TerrainDrawer.java Source code

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Here is the source code for org.jtrfp.mtmx.draw.TerrainDrawer.java

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/*
 * This file is part of mtmX.
 *
 * mtmX is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * mtmX is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with mtmX.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.jtrfp.mtmx.draw;

import static org.lwjgl.opengl.ARBBufferObject.GL_STATIC_DRAW_ARB;
import static org.lwjgl.opengl.ARBBufferObject.glBindBufferARB;
import static org.lwjgl.opengl.ARBBufferObject.glBufferDataARB;
import static org.lwjgl.opengl.ARBBufferObject.glGenBuffersARB;
import static org.lwjgl.opengl.ARBVertexBufferObject.GL_ARRAY_BUFFER_ARB;
import static org.lwjgl.opengl.ARBVertexBufferObject.GL_ELEMENT_ARRAY_BUFFER_ARB;
import static org.lwjgl.opengl.GL11.GL_FLOAT;
import static org.lwjgl.opengl.GL11.GL_VERTEX_ARRAY;
import static org.lwjgl.opengl.GL11.glEnableClientState;
import static org.lwjgl.opengl.GL11.glPopMatrix;
import static org.lwjgl.opengl.GL11.glPushMatrix;
import static org.lwjgl.opengl.GL11.glVertexPointer;

import java.nio.FloatBuffer;
import java.nio.IntBuffer;

import org.jtrfp.mtmx.Engine;
import org.jtrfp.mtmx.ITextureManager;
import org.jtrfp.mtmx.internal.VboUtil;
import org.jtrfp.mtmx.terrain.ITerrainMap;
import org.jtrfp.mtmx.texture.ITexture;
import org.jtrfp.mtmx.world.IWorld;
import org.lwjgl.BufferUtils;
import org.lwjgl.opengl.GL11;
import org.lwjgl.opengl.GLContext;

public class TerrainDrawer implements IDrawer {

    private final int vertexBufferId;

    private final int indexBufferId;

    private final int normalBufferId;

    private int renderMode = GL11.GL_TRIANGLES;

    private final int texCoordBufferId;

    private final VboUtil vboUtil;

    private final IWorld world;

    private final Engine engine;

    public TerrainDrawer(Engine engine, IWorld world) {
        this.engine = engine;
        this.world = world;

        enableClientStates();

        vboUtil = new VboUtil(world.getTerrainMap(), world.getClrData());

        // index buffer
        indexBufferId = createVboId();
        bufferElementData(indexBufferId, vboUtil.createIndexBuffer());

        // vertex buffer
        vertexBufferId = createVboId();
        bufferData(vertexBufferId, vboUtil.createVertexBuffer());

        // normal buffer
        normalBufferId = createVboId();
        bufferData(normalBufferId, vboUtil.createNormalBuffer());

        // tex coord
        texCoordBufferId = createVboId();
        bufferData(texCoordBufferId, vboUtil.createTexCoordBuffer());

        disableClientStates();
    }

    public ITerrainMap getTerrainMap() {
        return world.getTerrainMap();
    }

    @Override
    public void draw() {
        glPushMatrix();

        enableClientStates();
        bindBuffers();
        drawTextured();
        disableClientStates();

        glPopMatrix();

        unbindBuffers();
    }

    private void unbindBuffers() {
        glBindBufferARB(GL_ARRAY_BUFFER_ARB, 0);
        glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, 0);
    }

    private void bindBuffers() {
        // normals
        glBindBufferARB(GL_ARRAY_BUFFER_ARB, normalBufferId);
        GL11.glNormalPointer(GL_FLOAT, 0, 0);

        // vertexes
        glBindBufferARB(GL_ARRAY_BUFFER_ARB, vertexBufferId);
        glVertexPointer(3, GL_FLOAT, 0, 0);

        // textures
        glBindBufferARB(GL_ARRAY_BUFFER_ARB, texCoordBufferId);
        GL11.glTexCoordPointer(2, GL_FLOAT, 0, 0);

        // indexes
        glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, indexBufferId);
    }

    private void drawTextured() {
        int[] sizes = vboUtil.getSizes();
        int len = sizes.length;
        long offset = 0;

        String[] textureNames = world.getTexData().getTextureNames();
        ITextureManager textureManager = engine.getResourceManager().getTextureManager();

        for (int i = 0; i < len; i++) {
            int size = sizes[i];
            if (size > 0) {

                String name = textureNames[i];
                ITexture texture = textureManager.get(name);
                texture.bind();

                GL11.glDrawElements(renderMode, size, GL11.GL_UNSIGNED_INT, offset * (Integer.SIZE / 8));

                offset += size;
            }
        }
    }

    private void enableClientStates() {
        glEnableClientState(GL_VERTEX_ARRAY);
        glEnableClientState(GL11.GL_NORMAL_ARRAY);
        glEnableClientState(GL11.GL_TEXTURE_COORD_ARRAY);
    }

    private void disableClientStates() {
        glEnableClientState(GL_VERTEX_ARRAY);
        glEnableClientState(GL11.GL_NORMAL_ARRAY);
        glEnableClientState(GL11.GL_TEXTURE_COORD_ARRAY);
    }

    public static int createVboId() {
        if (GLContext.getCapabilities().GL_ARB_vertex_buffer_object) {
            IntBuffer buffer = BufferUtils.createIntBuffer(1);
            glGenBuffersARB(buffer);
            System.out.println("Created VBO ID: " + buffer.get(0));
            return buffer.get(0);
        }
        return 0;
    }

    public void bufferData(int id, FloatBuffer buffer) {
        if (GLContext.getCapabilities().GL_ARB_vertex_buffer_object) {
            glBindBufferARB(GL_ARRAY_BUFFER_ARB, id);
            glBufferDataARB(GL_ARRAY_BUFFER_ARB, buffer, GL_STATIC_DRAW_ARB);
        }
    }

    public void bufferElementData(int id, IntBuffer buffer) {
        if (GLContext.getCapabilities().GL_ARB_vertex_buffer_object) {
            glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, id);
            glBufferDataARB(GL_ELEMENT_ARRAY_BUFFER_ARB, buffer, GL_STATIC_DRAW_ARB);
        }
    }

    public int getRenderMode() {
        return renderMode;
    }

    public void setRenderMode(int renderMode) {
        this.renderMode = renderMode;
    }
}