| /* |
| * Copyright (C) 2009 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.gldual; |
| |
| import java.nio.ByteBuffer; |
| import java.nio.ByteOrder; |
| import java.nio.FloatBuffer; |
| import java.nio.ShortBuffer; |
| |
| import javax.microedition.khronos.egl.EGLConfig; |
| import javax.microedition.khronos.opengles.GL10; |
| |
| import android.opengl.GLSurfaceView; |
| import android.opengl.GLU; |
| import android.os.SystemClock; |
| |
| public class TriangleRenderer implements GLSurfaceView.Renderer{ |
| |
| public TriangleRenderer() { |
| mTriangle = new Triangle(); |
| } |
| |
| public void onSurfaceCreated(GL10 gl, EGLConfig config) { |
| /* |
| * By default, OpenGL enables features that improve quality |
| * but reduce performance. One might want to tweak that |
| * especially on software renderer. |
| */ |
| gl.glDisable(GL10.GL_DITHER); |
| |
| /* |
| * Some one-time OpenGL initialization can be made here |
| * probably based on features of this particular context |
| */ |
| gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, |
| GL10.GL_FASTEST); |
| |
| gl.glClearColor(.5f, .5f, .5f, 1); |
| gl.glShadeModel(GL10.GL_SMOOTH); |
| } |
| |
| public void onDrawFrame(GL10 gl) { |
| /* |
| * By default, OpenGL enables features that improve quality |
| * but reduce performance. One might want to tweak that |
| * especially on software renderer. |
| */ |
| gl.glDisable(GL10.GL_DITHER); |
| |
| /* |
| * Usually, the first thing one might want to do is to clear |
| * the screen. The most efficient way of doing this is to use |
| * glClear(). |
| */ |
| |
| gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT); |
| |
| /* |
| * Now we're ready to draw some 3D objects |
| */ |
| |
| gl.glMatrixMode(GL10.GL_MODELVIEW); |
| gl.glLoadIdentity(); |
| |
| GLU.gluLookAt(gl, 0, 0, -5, 0f, 0f, 0f, 0f, 1.0f, 0.0f); |
| |
| gl.glEnableClientState(GL10.GL_VERTEX_ARRAY); |
| |
| long time = SystemClock.uptimeMillis() % 4000L; |
| float angle = 0.090f * ((int) time); |
| |
| gl.glRotatef(angle, 0, 0, 1.0f); |
| |
| mTriangle.draw(gl); |
| } |
| |
| public void onSurfaceChanged(GL10 gl, int w, int h) { |
| gl.glViewport(0, 0, w, h); |
| |
| /* |
| * Set our projection matrix. This doesn't have to be done |
| * each time we draw, but usually a new projection needs to |
| * be set when the viewport is resized. |
| */ |
| |
| float ratio = (float) w / h; |
| gl.glMatrixMode(GL10.GL_PROJECTION); |
| gl.glLoadIdentity(); |
| gl.glFrustumf(-ratio, ratio, -1, 1, 3, 7); |
| |
| } |
| |
| private Triangle mTriangle; |
| } |
| |
| class Triangle { |
| public Triangle() { |
| |
| // Buffers to be passed to gl*Pointer() functions |
| // must be direct, i.e., they must be placed on the |
| // native heap where the garbage collector cannot |
| // move them. |
| // |
| // Buffers with multi-byte datatypes (e.g., short, int, float) |
| // must have their byte order set to native order |
| |
| ByteBuffer vbb = ByteBuffer.allocateDirect(VERTS * 3 * 4); |
| vbb.order(ByteOrder.nativeOrder()); |
| mFVertexBuffer = vbb.asFloatBuffer(); |
| |
| ByteBuffer tbb = ByteBuffer.allocateDirect(VERTS * 2 * 4); |
| tbb.order(ByteOrder.nativeOrder()); |
| |
| ByteBuffer ibb = ByteBuffer.allocateDirect(VERTS * 2); |
| ibb.order(ByteOrder.nativeOrder()); |
| mIndexBuffer = ibb.asShortBuffer(); |
| |
| // A unit-sided equalateral triangle centered on the origin. |
| float[] coords = { |
| // X, Y, Z |
| -0.5f, -0.25f, 0, |
| 0.5f, -0.25f, 0, |
| 0.0f, 0.559016994f, 0 |
| }; |
| |
| for (int i = 0; i < VERTS; i++) { |
| for(int j = 0; j < 3; j++) { |
| mFVertexBuffer.put(coords[i*3+j] * 2.0f); |
| } |
| } |
| |
| for(int i = 0; i < VERTS; i++) { |
| mIndexBuffer.put((short) i); |
| } |
| |
| mFVertexBuffer.position(0); |
| mIndexBuffer.position(0); |
| } |
| |
| public void draw(GL10 gl) { |
| gl.glFrontFace(GL10.GL_CCW); |
| gl.glVertexPointer(3, GL10.GL_FLOAT, 0, mFVertexBuffer); |
| gl.glDrawElements(GL10.GL_TRIANGLE_STRIP, VERTS, |
| GL10.GL_UNSIGNED_SHORT, mIndexBuffer); |
| } |
| |
| private final static int VERTS = 3; |
| |
| private FloatBuffer mFVertexBuffer; |
| private ShortBuffer mIndexBuffer; |
| } |