/*
* Copyright (c) 2013, Oskar Veerhoek
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* The views and conclusions contained in the software and documentation are those
* of the authors and should not be interpreted as representing official policies,
* either expressed or implied, of the FreeBSD Project.
*/
package episode_32;
import org.lwjgl.LWJGLException;
import org.lwjgl.input.Keyboard;
import org.lwjgl.opengl.ARBTextureRectangle;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import org.newdawn.slick.SlickException;
import org.newdawn.slick.UnicodeFont;
import org.newdawn.slick.font.effects.ColorEffect;
import utility.ImagingTools;
import static org.lwjgl.opengl.GL11.*;
/**
* Demonstrates face culling
*
* @author Oskar Veerhoek
*/
public class CullingTheoryDemo {
private static final String WINDOW_TITLE = "Culling!";
private static final int[] WINDOW_DIMENSIONS = {1280, 720};
private static enum RenderShape {TRIANGLES, LINES, POINTS}
private static enum CullState {FRONT, FRONT_AND_BACK, BACK, NONE,}
private static CullState cullState = CullState.NONE;
private static UnicodeFont font;
private static RenderShape renderShape = RenderShape.TRIANGLES;
private static void render() {
glClear(GL_COLOR_BUFFER_BIT);
glMatrixMode(GL_PROJECTION);
glOrtho(0, 1280, 720, 0, 1, -1);
glMatrixMode(GL_MODELVIEW);
glPushAttrib(GL_ENABLE_BIT);
glDisable(GL_CULL_FACE);
font.drawString(15, 15, "Drawing: " + renderShape.toString());
font.drawString(15, 35, "Culling: " + cullState.toString());
glPopAttrib();
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glMatrixMode(GL_MODELVIEW);
switch (renderShape) {
case TRIANGLES:
glBegin(GL_TRIANGLES);
glColor3d(1, 0, 0);
glVertex2d(-0.75, -0.85);
glColor3d(0, 1, 0);
glVertex2d(+0.75, -0.85);
glColor3d(0, 0, 1);
glVertex2d(+0.00, +0.85);
glEnd();
break;
case LINES:
glColor3d(1, 1, 1);
glBegin(GL_LINES);
glVertex2d(-0.75, +0.75);
glVertex2d(+0.75, -0.75);
glEnd();
break;
case POINTS:
glColor3d(1, 1, 1);
glBegin(GL_POINTS);
glVertex2d(-0.5, +0.5);
glVertex2d(+0.5, +0.5);
glVertex2d(+0.5, -0.5);
glVertex2d(-0.5, -0.5);
glEnd();
break;
}
}
private static void logic() {
}
@SuppressWarnings("unchecked")
private static void setUpFonts() {
java.awt.Font awtFont = new java.awt.Font("Helvetica", java.awt.Font.BOLD, 18);
font = new UnicodeFont(awtFont);
font.getEffects().add(new ColorEffect(java.awt.Color.white));
font.addAsciiGlyphs();
try {
font.loadGlyphs();
} catch (SlickException e) {
e.printStackTrace();
cleanUp(true);
}
}
private static void input() {
while (Keyboard.next()) {
if (Keyboard.getEventKeyState()) {
switch (Keyboard.getEventKey()) {
case Keyboard.KEY_F:
cullState = CullState.FRONT;
glEnable(GL_CULL_FACE);
glCullFace(GL_FRONT);
break;
case Keyboard.KEY_B:
cullState = CullState.BACK;
glEnable(GL_CULL_FACE);
glCullFace(GL_BACK);
break;
case Keyboard.KEY_N:
cullState = CullState.NONE;
glDisable(GL_CULL_FACE);
break;
case Keyboard.KEY_A:
cullState = CullState.FRONT_AND_BACK;
glEnable(GL_CULL_FACE);
glCullFace(GL_FRONT_AND_BACK);
break;
case Keyboard.KEY_P:
renderShape = RenderShape.POINTS;
break;
case Keyboard.KEY_L:
renderShape = RenderShape.LINES;
break;
case Keyboard.KEY_T:
renderShape = RenderShape.TRIANGLES;
break;
}
}
}
}
private static void setUpTextures() {
int loadingTexture = ImagingTools.glLoadLinearPNG("res/images/loading16x9.png");
glPushAttrib(GL_ENABLE_BIT);
glEnable(ARBTextureRectangle.GL_TEXTURE_RECTANGLE_ARB);
glBindTexture(ARBTextureRectangle.GL_TEXTURE_RECTANGLE_ARB, loadingTexture);
glBegin(GL_QUADS);
glTexCoord2d(0, 0);
glVertex2d(-1, +1);
glTexCoord2d(0, 720);
glVertex2d(-1, -1);
glTexCoord2d(1280, 720);
glVertex2d(+1, -1);
glTexCoord2d(1280, 0);
glVertex2d(+1, +1);
glEnd();
glFlush();
Display.update();
glBindTexture(ARBTextureRectangle.GL_TEXTURE_RECTANGLE_ARB, 0);
glPopAttrib();
glDeleteTextures(loadingTexture);
}
private static void setUpStates() {
glEnable(GL_CULL_FACE);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glLineWidth(3);
glPointSize(3);
}
private static void cleanUp(boolean asCrash) {
font.destroy();
Display.destroy();
System.exit(asCrash ? 1 : 0);
}
private static void update() {
Display.update();
}
private static void enterGameLoop() {
while (!Display.isCloseRequested()) {
render();
logic();
input();
update();
}
}
private static void setUpDisplay() {
try {
Display.setDisplayMode(new DisplayMode(WINDOW_DIMENSIONS[0], WINDOW_DIMENSIONS[1]));
Display.setVSyncEnabled(true);
Display.setTitle(WINDOW_TITLE);
Display.create();
} catch (LWJGLException e) {
e.printStackTrace();
cleanUp(true);
}
}
public static void main(String[] args) {
setUpDisplay();
setUpTextures();
setUpFonts();
setUpStates();
enterGameLoop();
cleanUp(false);
}
}