Android版OpenGL ES 2.0中的纹理
我是OpenGL的新手，我通过为ES 2.0制作Android游戏来教我自己。 我首先创建一个“Sprite”类，创建一个平面并为其呈现纹理。 为了练习，我有两个在同一个地方交替绘制的Sprite对象。 在ES 1.0中，我得到了很多很好的工作，但现在我已经切换到2.0了，我得到了一个没有错误的黑屏 。 我很努力想弄清楚我做错了什么，但我有强烈的感觉，它与我的着色器有关。 我将在这里转储所有相关的代码，希望有人可以给我一个答案或一些建议，说明我做错了什么。 如果我不明白我做错了什么，或许就如何解决问题提供一些建议？ 预先感谢您浏览我即将发布的所有代码。
我发布的三个课程是：
GameRenderer - 我的GLSurfaceView的渲染器
着色器 - 创建着色器程序对象
Sprite - 创建一个正方形并在其上绘制纹理
另外，我会发布我的顶点和片段着色器源代码。
我认为相关的课程不够贴切：
GameActivity
GameView - 一个GLSurfaceView
GameLoopThread - 我的主要游戏循环
FPSCounter - 每100帧输出平均FPS至logcat。
GameRender类：
package com.detour.raw;
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;
import android.content.Context;
import android.graphics.Bitmap;
import android.opengl.GLES20;
import android.opengl.GLU;
import android.opengl.Matrix;
import android.opengl.GLSurfaceView;
public class GameRenderer implements GLSurfaceView.Renderer{
private static final String LOG_TAG = GameRenderer.class.getSimpleName();
Context mContext;
Bitmap bitmap;
private float red = 0.0f;
private float green = 0.0f;
private float blue = 0.0f;
Shader shader;
FPSCounter fps;
Sprite sprite;
Sprite sprite2;
int x = 0;
private float[] mProjMatrix = new float[16];
private float[] mVMatrix = new float[16];
//int[] vertexShader;
//int[] fragmentShader;
//int program;
//String vShaderSource = "";
//String fShaderSource = "";
public GameRenderer(Context context){
mContext = context;
//create objects/sprites
sprite = new Sprite(mContext);
sprite2 = new Sprite(mContext);
fps = new FPSCounter();
}
@Override
public void onDrawFrame(GL10 gl) {
GLES20.glClearColor(red, green, blue, 1.0f);
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
if(x>3){
x=0;
}
if(x%2==0){
sprite.draw(gl);
}else{
sprite2.draw(gl);
}
x++;
fps.calculate();
//fps.draw(gl);
}
@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
GLES20.glViewport(0, 0, width, height);
float ratio = (float)(width/height);
Matrix.frustumM(mProjMatrix, 0, -ratio, ratio, -1, 1, 0.5f, 10);
}
@Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
// TODO Auto-generated method stub
GLES20.glEnable(GLES20.GL_TEXTURE_2D);
GLES20.glEnable(GLES20.GL_DEPTH_TEST);
GLES20.glClearDepthf(1.0f);
GLES20.glDepthFunc(GLES20.GL_LEQUAL);
GLES20.glDepthMask(true);
GLES20.glEnable(GLES20.GL_CULL_FACE);
GLES20.glCullFace(GLES20.GL_BACK);
GLES20.glClearColor(red, green, blue, 1.0f);
//load sprite/object textures (preferably loop through an array of all sprites).
sprite.loadGLTexture(gl, mContext, R.drawable.raw1);
sprite2.loadGLTexture(gl, mContext, R.drawable.raw2);
Matrix.setLookAtM(mVMatrix, 0, 0, 0, -5.0f, 0.0f, 0f, 0f, 0f, 0.0f, 0.0f);
System.gc();
}
}
着色器类：
package com.detour.raw;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import android.content.Context;
import android.opengl.GLES20;
import android.util.Log;
public class Shader {
public static final String TAG = Shader.class.getSimpleName();
int program;
int vertexShader;
int fragmentShader;
String vShaderSource;
String fShaderSource;
public Shader(){
//blank constructor
//createProgram();
}
public Shader(String vs_source, String fs_source){
this.vShaderSource = vs_source;
this.fShaderSource = fs_source;
createProgram();
}
public Shader(int vs_source_id, int fs_source_id, Context context) {
StringBuffer vs = new StringBuffer();
StringBuffer fs = new StringBuffer();
try{
InputStream inputStream = context.getResources().openRawResource(vs_source_id);
BufferedReader in = new BufferedReader(new InputStreamReader(inputStream));
String read = in.readLine();
while (read != null) {
vs.append(read + "n");
read = in.readLine();
}
vs.deleteCharAt(vs.length() - 1);
inputStream = context.getResources().openRawResource(fs_source_id);
in = new BufferedReader(new InputStreamReader(inputStream));
read = in.readLine();
while (read != null) {
fs.append(read + "n");
read = in.readLine();
}
fs.deleteCharAt(fs.length() - 1);
}catch (Exception e){
Log.d("ERROR-readingShader", "Could not read shader: " + e.getLocalizedMessage());
}
this.vShaderSource = vs.toString();
this.fShaderSource = fs.toString();
createProgram();
}
private void createProgram(){
program = GLES20.glCreateProgram();
if(program!=0){
vertexShader = createShader(GLES20.GL_VERTEX_SHADER, vShaderSource);
fragmentShader = createShader(GLES20.GL_FRAGMENT_SHADER, fShaderSource);
GLES20.glAttachShader(program, vertexShader);
GLES20.glAttachShader(program, fragmentShader);
GLES20.glLinkProgram(program);
}else{
Log.e(TAG, "Couldn't create program.");
}
}
private int createShader(int type, String source){
int shader = GLES20.glCreateShader(type);
if(shader!=0){
GLES20.glShaderSource(shader, source);
GLES20.glCompileShader(shader);
}
return shader;
}
public int getProgram(){
return program;
}
雪碧类：
package com.detour.raw;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.nio.IntBuffer;
import java.nio.ShortBuffer;
import javax.microedition.khronos.opengles.GL10;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.opengl.GLES20;
import android.opengl.GLUtils;
public class Sprite {
//public static final int FRAME_WIDTH = 64;
//public static final int FRAME_HEIGHT = 64;
private static final String LOG_TAG = Sprite.class.getSimpleName();
Context mContext;
Bitmap bitmap;
private int textureLoc;
private int vertexLoc;
private int[] textures = new int[1];
//private int[] pixels;
/*private float textureCoordinates[] = {
0.0f, 0.0f,
0.0f, 1.0f,
1.0f, 1.0f,
1.0f, 0.0f};*/
private float vertices[] = {
-1.0f, 1.0f,// 0.0f,
-1.0f, -1.0f,// 0.0f,
1.0f, -1.0f,// 0.0f,
1.0f, 1.0f// 0.0f
};
private short[] indices = {
0, 1, 2,
0, 2, 3};
private FloatBuffer vertexBuffer;
//private IntBuffer textureBuffer;
private ShortBuffer indexBuffer;
Shader shader;
int program;
String vShaderSource = "";
String fShaderSource = "";
public Sprite(Context context){
mContext = context;
ByteBuffer vbb = ByteBuffer.allocateDirect(vertices.length * 4);
vbb.order(ByteOrder.nativeOrder());
vertexBuffer = vbb.asFloatBuffer();
vertexBuffer.put(vertices);
vertexBuffer.position(0);
ByteBuffer ibb = ByteBuffer.allocateDirect(indices.length * 2);
ibb.order(ByteOrder.nativeOrder());
indexBuffer = ibb.asShortBuffer();
indexBuffer.put(indices);
indexBuffer.position(0);
}
public void draw(GL10 gl) {
GLES20.glDrawElements(GLES20.GL_TRIANGLES, indices.length, GLES20.GL_FLOAT, indexBuffer);
}
public void loadGLTexture(GL10 gl, Context context, int id){
shader = new Shader(R.raw.sprite_vs, R.raw.sprite_fs, mContext);
program = shader.getProgram();
GLES20.glUseProgram(program);
vertexLoc = GLES20.glGetAttribLocation(program, "a_position");
textureLoc = GLES20.glGetUniformLocation(program, "u_texture"); //texture
InputStream is = context.getResources().openRawResource(id);
try {
bitmap = BitmapFactory.decodeStream(is);
} finally {
try {
is.close();
is = null;
} catch (IOException e) {
}
}
//pixels = new int[(bitmap.getWidth()*bitmap.getHeight())];
//bitmap.getPixels(pixels, 0, bitmap.getWidth(), 0, 0, bitmap.getWidth(), bitmap.getHeight());
/*ByteBuffer byteBuf = ByteBuffer.allocateDirect(pixels.length * 4);
byteBuf.order(ByteOrder.nativeOrder());
textureBuffer = byteBuf.asIntBuffer();
textureBuffer.put(pixels);
textureBuffer.position(0);*/
GLES20.glDeleteTextures(1, textures, 0);
GLES20.glGenTextures(1, textures, 0);
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textures[0]);
GLES20.glUniform1i(textureLoc, 0);
GLES20.glEnableVertexAttribArray(vertexLoc);
GLES20.glVertexAttribPointer(vertexLoc, 2, GLES20.GL_FLOAT, false, 0, vertexBuffer);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_LINEAR);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_LINEAR);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_REPEAT);
GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_REPEAT);
//GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_RGBA, FRAME_WIDTH, FRAME_HEIGHT, 0, GLES20.GL_RGBA, GLES20.GL_UNSIGNED_BYTE, byteBuf);//(GLES20.GL_TEXTURE_2D, 0, bitmap, 0);
GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, bitmap, 0);
bitmap.recycle();
}
}
顶点着色器（sprite_vs.txt）：
#version 110
attribute vec2 a_position;
varying vec2 v_texcoord;
void main()
{
gl_Position = vec4(a_position, 0.0, 1.0);
v_texcoord = a_position * vec2(0.5) + vec2(0.5);
}
片段（像素）着色器（sprite_fs.txt）：
#version 110
uniform sampler2D u_texture;
varying vec2 v_texcoord;
void main()
{
gl_FragColor = texture2D(u_texture, v_texcoord);
}
非常感谢你，如果你真的花时间来看看这个！ 希望别人也可以将它作为未来的资源。
一些观察/问题：
我不知道你如何改变片段着色器，但是当前发布的版本需要一个精度说明符。 只需添加：
precision mediump float;
到顶部，它应该工作。 现在关于黑屏这里有一些问题：
当你将glClearColor改为非黑色并将所有绘制命令注释掉时，它仍然看起来是黑色的吗？ 如果是这样，那么你的问题比纹理更大。
其次，如果您忽略纹理输出并尝试将每个精灵绘制为没有纹理数据的平面彩色矩形，您会得到什么？ 你应该可以在屏幕上看到一些彩色的矩形。
最后，在调用glDrawElements之前，您需要绑定纹理。 （虽然在这个例子中这不重要，因为你还没有改变状态。）