CG[LWJGL0006] || Menggambar Segi Tiga dan Segi Empat

Table of contents


Pada postingan kali ini kita akan menggambar dua buah objek geometris yaitu sebuah segi tiga dan sebuah segi empat dalam satu window OpenGL. materi ini adalah penggabungan dari materi tentang menggambar segi tiga dan materi tentang menggambar segi empat. berikut ini source code lengkapnya:

import org.lwjgl.LWJGLException;
import org.lwjgl.Sys;
import org.lwjgl.input.Keyboard;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;

import org.lwjgl.opengl.GL11;
import org.lwjgl.util.glu.GLU;


public class TutorialLWJGL0006 {

String windowTitle = "CG[LWJGL0006] || Menggambar Segi Tiga dan Segi Empat";
public boolean closeRequested = false;

public void run() {
createWindow();
initializeGL();

// main loop
while (!closeRequested) {
pollInput();
updateLogic();
renderGL();
Display.update();
}

cleanup();
}

private void initializeGL() {
int width = Display.getDisplayMode().getWidth();
int height = Display.getDisplayMode().getHeight();

GL11.glViewport(0, 0, width, height); // Reset The Current Viewport
GL11.glMatrixMode(GL11.GL_PROJECTION); // Select The Projection Matrix
GL11.glLoadIdentity(); // Reset The Projection Matrix
GLU.gluPerspective(45.0f, ((float) width / (float) height), 0.1f, 100.0f); // Calculate The Aspect Ratio Of The Window
GL11.glMatrixMode(GL11.GL_MODELVIEW); // Select The Modelview Matrix
GL11.glLoadIdentity(); // Reset The Modelview Matrix

GL11.glShadeModel(GL11.GL_SMOOTH); // Enables Smooth Shading
GL11.glClearColor(0.20392156862f, 0.59607843137f, 0.85882352941f, 0.0f);
GL11.glClearDepth(1.0f); // Depth Buffer Setup
GL11.glEnable(GL11.GL_DEPTH_TEST); // Enables Depth Testing
GL11.glDepthFunc(GL11.GL_LEQUAL); // The Type Of Depth Test To Do
GL11.glHint(GL11.GL_PERSPECTIVE_CORRECTION_HINT, GL11.GL_NICEST); // Really Nice Perspective Calculations
}

private void updateLogic() {
//
}

private void renderGL() {
GL11.glClear(GL11.GL_COLOR_BUFFER_BIT | GL11.GL_DEPTH_BUFFER_BIT); // Clear The Screen And The Depth Buffer
GL11.glLoadIdentity(); // Reset The View
GL11.glTranslatef(-1.5f, 0.0f, -6.0f);
GL11.glBegin(GL11.GL_TRIANGLES); // Drawing Using Triangles
GL11.glColor3f(231.0f/255.0f, 76.0f/255.0f, 60.0f/255.0f);
GL11.glVertex3f(0.0f, 1.0f, 0.0f); // Top
GL11.glColor3f(80.0f/255.0f, 46.0f/255.0f, 204.0f/255.0f);
GL11.glVertex3f(-1.0f, -1.0f, 0.0f); // Bottom Left
GL11.glColor3f(241.0f/255.0f, 196.0f/255.0f, 15.0f/255.0f);
GL11.glVertex3f(1.0f, -1.0f, 0.0f); // Bottom Right
GL11.glEnd(); // Finished Drawing The Triangle
GL11.glTranslatef(3.0f, 0.0f, 0.0f); // Move Right 3 Units
GL11.glBegin(GL11.GL_QUADS); // Draw A Quad
GL11.glColor3f(243.0f/255.0f, 156.0f/255.0f, 18.0f/255.0f);
GL11.glVertex3f(-1.0f, 1.0f, 0.0f); // Top Left
GL11.glColor3f(211.0f/255.0f, 84.0f/255.0f, 0.0f/255.0f);
GL11.glVertex3f(1.0f, 1.0f, 0.0f); // Top Right
GL11.glColor3f(192.0f/255.0f, 57.0f/255.0f, 43.0f/255.0f);
GL11.glVertex3f(1.0f, -1.0f, 0.0f); // Bottom Right
GL11.glColor3f(39.0f/255.0f, 174.0f/255.0f, 96.0f/255.0f);
GL11.glVertex3f(-1.0f, -1.0f, 0.0f); // Bottom Left
GL11.glEnd(); // Done Drawing The Quad
}

public void pollInput() {

// scroll through key events
while (Keyboard.next()) {
if (Keyboard.getEventKeyState()) {
if (Keyboard.getEventKey() == Keyboard.KEY_ESCAPE)
closeRequested = true;
}
}

if (Display.isCloseRequested()) {
closeRequested = true;
}
}

private void createWindow() {
try {
Display.setDisplayMode(new DisplayMode(640, 480));
Display.setVSyncEnabled(true);
Display.setTitle(windowTitle);
Display.create();
} catch (LWJGLException e) {
Sys.alert("Error", "Initialization failed!\n\n" + e.getMessage());
System.exit(0);
}
}

private void cleanup() {
Display.destroy();
}

public static void main(String[] args) {
TutorialLWJGL0006 tutorial = new TutorialLWJGL0006();
tutorial.run();
}

}

hasilnya diperlihatkan pada gambar berikut:

lihat semua tutorial

Referensi:
- http://wiki.lwjgl.org/index.php?title=Main_Page
- http://nehe.gamedev.net/
- http://computergraphicsindonesia.blogspot.com/2015/01/cglwjgl0004-menggambar-segitiga.html
- http://computergraphicsindonesia.blogspot.com/2015/01/cglwjgl0005-menggambar-segi-empat.html