|
This example shows how to implement masking with JOGL.
This is the Java port of the one of the NeHe OpenGL tutorials.
You can get complete IntelliJ IDEA project structure (all source, resources, build script, …) by downloading the source distribution from here.
The original post of the programmer who ported the examples can be found here.
package demos.nehe.lesson20;
import demos.common.GLDisplay;
/**
* @author Pepijn Van Eeckhoudt
*/
public class Lesson20 {
public static void main(String[] args) {
GLDisplay neheGLDisplay = GLDisplay.createGLDisplay("Lesson 20: Masking");
Renderer renderer = new Renderer();
InputHandler inputHandler = new InputHandler(renderer, neheGLDisplay);
neheGLDisplay.addGLEventListener(renderer);
neheGLDisplay.addKeyListener(inputHandler);
neheGLDisplay.start();
}
}
package demos.nehe.lesson20;
import demos.common.GLDisplay;
import javax.swing.*;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
class InputHandler extends KeyAdapter {
private Renderer renderer;
public InputHandler(Renderer renderer, GLDisplay glDisplay) {
this.renderer = renderer;
glDisplay.registerKeyStrokeForHelp(
KeyStroke.getKeyStroke(KeyEvent.VK_M, 0), "Toggle masking");
glDisplay.registerKeyStrokeForHelp(
KeyStroke.getKeyStroke(KeyEvent.VK_SPACE, 0), "Switch scene");
}
public void keyReleased(KeyEvent e) {
switch (e.getKeyCode()) {
case KeyEvent.VK_M:
renderer.toggleMasking();
break;
case KeyEvent.VK_SPACE:
renderer.switchScene();
break;
}
}
}
package demos.nehe.lesson20;
import demos.common.TextureReader;
import javax.media.opengl.GL;
import javax.media.opengl.GLAutoDrawable;
import javax.media.opengl.GLEventListener;
import javax.media.opengl.glu.GLU;
import java.io.IOException;
class Renderer implements GLEventListener {
boolean maskingEnabled = true; // Masking On/Off
boolean scene; // Which Scene To Draw
int[] textures = new int[5]; // Storage For Our Five Textures
int loop; // Generic Loop Variable
float roll; // Rolling Texture
private GLU glu = new GLU();
public Renderer() {
}
public void toggleMasking() {
maskingEnabled = !maskingEnabled;
}
public void switchScene() {
scene = !scene;
}
public void loadGLTextures(GL gl) throws IOException {
String tileNames [] =
{"demos/data/images/logo.png",
"demos/data/images/mask1.png",
"demos/data/images/image1.png",
"demos/data/images/mask2.png",
"demos/data/images/image2.png"
};
gl.glGenTextures(5, textures, 0);
for (int i = 0; i < 5; i++) {
TextureReader.Texture texture = TextureReader.readTexture(tileNames[i]);
//Create Nearest Filtered Texture
gl.glBindTexture(GL.GL_TEXTURE_2D, textures[i]);
gl.glTexParameteri(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MAG_FILTER, GL.GL_LINEAR);
gl.glTexParameteri(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MIN_FILTER, GL.GL_LINEAR);
gl.glTexImage2D(GL.GL_TEXTURE_2D,
0,
3,
texture.getWidth(),
texture.getHeight(),
0,
GL.GL_RGB,
GL.GL_UNSIGNED_BYTE,
texture.getPixels());
}
}
public void init(GLAutoDrawable glDrawable) {
GL gl = glDrawable.getGL();
try {
loadGLTextures(gl);
} catch (IOException e) {
throw new RuntimeException(e);
}
gl.glShadeModel(GL.GL_SMOOTH); // Enables Smooth Color Shading
// This Will Clear The Background Color To Black
gl.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
gl.glClearDepth(1.0); // Enables Clearing Of The Depth Buffer
gl.glEnable(GL.GL_DEPTH_TEST); // Enables Depth Testing
gl.glDepthFunc(GL.GL_LEQUAL); // The Type Of Depth Test To Do
// Really Nice Perspective Calculations
gl.glHint(GL.GL_PERSPECTIVE_CORRECTION_HINT, GL.GL_NICEST);
gl.glEnable(GL.GL_TEXTURE_2D);
}
public void display(GLAutoDrawable glDrawable) {
GL gl = glDrawable.getGL();
// Clear The Screen And The Depth Buffer
gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT);
gl.glLoadIdentity(); // Reset The View
gl.glTranslatef(0.0f, 0.0f, -2.0f); // Move Into The Screen 5 Units
gl.glBindTexture(GL.GL_TEXTURE_2D, textures[0]); // Select Our Logo Texture
gl.glBegin(GL.GL_QUADS); // Start Drawing A Textured Quad
gl.glTexCoord2f(0.0f, -roll + 0.0f);
gl.glVertex3f(-1.1f, -1.1f, 0.0f); // Bottom Left
gl.glTexCoord2f(3.0f, -roll + 0.0f);
gl.glVertex3f(1.1f, -1.1f, 0.0f); // Bottom Right
gl.glTexCoord2f(3.0f, -roll + 3.0f);
gl.glVertex3f(1.1f, 1.1f, 0.0f); // Top Right
gl.glTexCoord2f(0.0f, -roll + 3.0f);
gl.glVertex3f(-1.1f, 1.1f, 0.0f); // Top Left
gl.glEnd(); // Done Drawing The Quad
gl.glEnable(GL.GL_BLEND); // Enable Blending
gl.glDisable(GL.GL_DEPTH_TEST); // Disable Depth Testing
if (maskingEnabled) // Is Masking Enabled?
{
// Blend Screen Color With Zero (Black)
gl.glBlendFunc(GL.GL_DST_COLOR, GL.GL_ZERO);
}
if (scene) // Are We Drawing The Second Scene?
{
gl.glTranslatef(0.0f, 0.0f, -1.0f); // Translate Into The Screen One Unit
gl.glRotatef(roll * 360, 0.0f, 0.0f, 1.0f); // Rotate On The Z Axis 360 Degrees.
if (maskingEnabled) // Is Masking On?
{
// Select The Second Mask Texture
gl.glBindTexture(GL.GL_TEXTURE_2D, textures[3]);
gl.glBegin(GL.GL_QUADS); // Start Drawing A Textured Quad
gl.glTexCoord2f(0.0f, 0.0f);
gl.glVertex3f(-1.1f, -1.1f, 0.0f); // Bottom Left
gl.glTexCoord2f(1.0f, 0.0f);
gl.glVertex3f(1.1f, -1.1f, 0.0f); // Bottom Right
gl.glTexCoord2f(1.0f, 1.0f);
gl.glVertex3f(1.1f, 1.1f, 0.0f); // Top Right
gl.glTexCoord2f(0.0f, 1.0f);
gl.glVertex3f(-1.1f, 1.1f, 0.0f); // Top Left
gl.glEnd(); // Done Drawing The Quad
}
gl.glBlendFunc(GL.GL_ONE, GL.GL_ONE); // Copy Image 2 Color To The Screen
// Select The Second Image Texture
gl.glBindTexture(GL.GL_TEXTURE_2D, textures[4]);
gl.glBegin(GL.GL_QUADS); // Start Drawing A Textured Quad
gl.glTexCoord2f(0.0f, 0.0f);
gl.glVertex3f(-1.1f, -1.1f, 0.0f); // Bottom Left
gl.glTexCoord2f(1.0f, 0.0f);
gl.glVertex3f(1.1f, -1.1f, 0.0f); // Bottom Right
gl.glTexCoord2f(1.0f, 1.0f);
gl.glVertex3f(1.1f, 1.1f, 0.0f); // Top Right
gl.glTexCoord2f(0.0f, 1.0f);
gl.glVertex3f(-1.1f, 1.1f, 0.0f); // Top Left
gl.glEnd(); // Done Drawing The Quad
} else // Otherwise
{
if (maskingEnabled) // Is Masking On?
{
// Select The First Mask Texture
gl.glBindTexture(GL.GL_TEXTURE_2D, textures[1]);
// Start Drawing A Textured Quad
gl.glBegin(GL.GL_QUADS);
gl.glTexCoord2f(roll + 0.0f, 0.0f);
gl.glVertex3f(-1.1f, -1.1f, 0.0f); // Bottom Left
gl.glTexCoord2f(roll + 4.0f, 0.0f);
gl.glVertex3f(1.1f, -1.1f, 0.0f); // Bottom Right
gl.glTexCoord2f(roll + 4.0f, 4.0f);
gl.glVertex3f(1.1f, 1.1f, 0.0f); // Top Right
gl.glTexCoord2f(roll + 0.0f, 4.0f);
gl.glVertex3f(-1.1f, 1.1f, 0.0f); // Top Left
gl.glEnd(); // Done Drawing The Quad
}
gl.glBlendFunc(GL.GL_ONE, GL.GL_ONE); // Copy Image 1 Color To The Screen
// Select The First Image Texture
gl.glBindTexture(GL.GL_TEXTURE_2D, textures[2]);
gl.glBegin(GL.GL_QUADS); // Start Drawing A Textured Quad
gl.glTexCoord2f(roll + 0.0f, 0.0f);
gl.glVertex3f(-1.1f, -1.1f, 0.0f); // Bottom Left
gl.glTexCoord2f(roll + 4.0f, 0.0f);
gl.glVertex3f(1.1f, -1.1f, 0.0f); // Bottom Right
gl.glTexCoord2f(roll + 4.0f, 4.0f);
gl.glVertex3f(1.1f, 1.1f, 0.0f); // Top Right
gl.glTexCoord2f(roll + 0.0f, 4.0f);
gl.glVertex3f(-1.1f, 1.1f, 0.0f); // Top Left
gl.glEnd(); // Done Drawing The Quad
}
gl.glEnable(GL.GL_DEPTH_TEST); // Enable Depth Testing
gl.glDisable(GL.GL_BLEND); // Disable Blending
roll += 0.002f; // Increase Our Texture Roll Variable
if (roll > 1.0f) // Is Roll Greater Than One
{
roll -= 1.0f; // Subtract 1 From Roll
}
}
public void reshape(GLAutoDrawable glDrawable, int x, int y, int w, int h) {
if (h == 0) h = 1;
GL gl = glDrawable.getGL();
// Reset The Current Viewport And Perspective Transformation
gl.glViewport(0, 0, w, h);
gl.glMatrixMode(GL.GL_PROJECTION); // Select The Projection Matrix
gl.glLoadIdentity(); // Reset The Projection Matrix
// Calculate The Aspect Ratio Of The Window
glu.gluPerspective(45.0f, (float) w / (float) h, 0.1f, 100.0f);
gl.glMatrixMode(GL.GL_MODELVIEW); // Select The Modelview Matrix
gl.glLoadIdentity(); // Reset The ModalView Matrix
}
public void displayChanged(GLAutoDrawable glDrawable, boolean b, boolean b1) {
}
}
|
Related Tips
|
Other API Tips 
You can share your information about this topic using the form below!
Please do not post your questions with this form! Thanks.