现在我正在尝试为一个小游戏创建图形。首先，我试图制造我的障碍。这些只是矩形。我尝试使所有数据（对于所有矩形都相同）都是静态的。颜色，起始位置，着色器。我正在尝试这样做，导致一个有效的早期版本，有性能问题。当我开始工作时，我也想切换到 VBO。这些对象将被单独移动和缩放（尚未在代码中）。
我想尝试我的代码，但我遇到了一个我不明白的错误。这是我的日志猫输出
04-08 15:03:05.573: E/AndroidRuntime(3051): FATAL EXCEPTION: GLThread 4926
04-08 15:03:05.573: E/AndroidRuntime(3051): Process: com.example.jump, PID: 3051
04-08 15:03:05.573: E/AndroidRuntime(3051): java.lang.IllegalArgumentException: length - offset < count*4 < needed
04-08 15:03:05.573: E/AndroidRuntime(3051): at android.opengl.GLES20.glUniform4fv(Native Method)
04-08 15:03:05.573: E/AndroidRuntime(3051): at com.example.jump.ObstacleGL.initialize(ObstacleGL.java:82)
04-08 15:03:05.573: E/AndroidRuntime(3051): at com.example.jump.GameRenderer.onSurfaceCreated(GameRenderer.java:57)
04-08 15:03:05.573: E/AndroidRuntime(3051): at android.opengl.GLSurfaceView$GLThread.guardedRun(GLSurfaceView.java:1501)
04-08 15:03:05.573: E/AndroidRuntime(3051): at android.opengl.GLSurfaceView$GLThread.run(GLSurfaceView.java:1240)
这让我感到困惑，长度是 3，偏移量是 0，计数*4 是 4。我不知道"需要"是什么价值。我认为这是陈述失败的地方。
这是我的班级。我在 onSurfacecreate 中调用初始化方法
package com.example.jump;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.nio.ShortBuffer;
import android.opengl.GLES20;
import android.opengl.Matrix;
public class ObstacleGL {
static final int COORDS_PER_VERTEX = 3;
static final int vertexStride = COORDS_PER_VERTEX * 4;
private static final String vertexShaderCode =
"uniform mat4 uMVPMatrix;" +
"attribute vec4 vPosition;" +
"void main() {" +
" gl_Position = uMVPMatrix * vPosition;" +
"}";
private static final String fragmentShaderCode =
"precision mediump float;" +
"uniform vec4 vColor;" +
"void main() {" +
" gl_FragColor = vColor;" +
"}";
private static float [] coords={
//x,y,z z=0
1,1,0, //ol
1,0,0, //ul
1.2f,0,0, //ur
1.2f,1,0 //or
};
private static final short[] drawOrder = { 0, 1, 2, 0, 2, 3 };
private static int fragmentShader;
private static int vertexShader;
private static int mProgram;
private static float[] color={0.33f,1,0.33f};
private static int colorHandle;
private static int positionHandle;
private static FloatBuffer vertexBuffer;
private static ShortBuffer drawListBuffer;
//Gamelogic
public final int id;
private float x,y,height,width;
private float xOffset,yOffset;
//Opengl
private int matrixHandle;
private int vertexCount;
private float[] translationMatrix=new float[16];
public static void initialize(){
fragmentShader=GameRenderer.loadShader(GLES20.GL_FRAGMENT_SHADER,fragmentShaderCode);
vertexShader=GameRenderer.loadShader(GLES20.GL_VERTEX_SHADER, vertexShaderCode);
ByteBuffer bb;
ByteBuffer dlb;
bb= ByteBuffer.allocateDirect(coords.length*4);
bb.order(ByteOrder.nativeOrder());
vertexBuffer=bb.asFloatBuffer();
vertexBuffer.put(coords);
vertexBuffer.position(0);
dlb=ByteBuffer.allocateDirect(12); //drawOrder.length*2
dlb.order(ByteOrder.nativeOrder());
drawListBuffer=dlb.asShortBuffer();
drawListBuffer.put(drawOrder);
drawListBuffer.position(0);
mProgram=GLES20.glCreateProgram();
GLES20.glAttachShader(mProgram, fragmentShader);
GLES20.glAttachShader(mProgram, vertexShader);
colorHandle=GLES20.glGetUniformLocation(mProgram, "vColor");
positionHandle=GLES20.glGetAttribLocation(mProgram, "vPosition");
GLES20.glLinkProgram(mProgram);
GLES20.glVertexAttribPointer(positionHandle, COORDS_PER_VERTEX, GLES20.GL_FLOAT, false,vertexStride , vertexBuffer);
GLES20.glUniform4fv(colorHandle, 1, color,0);
}
public ObstacleGL(int id,float x, float y, float height,float width)
{
this.id=id;
//not used at the moment
this.x=x;
this.xOffset=0;
this.y=0;
this.yOffset=0;
this.height=height;
this.width=width;
//
vertexCount=coords.length/COORDS_PER_VERTEX;
Matrix.setIdentityM(translationMatrix, 0);
//getting the handle to set new translations
matrixHandle=GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
}
public void draw()
{
GLES20.glUseProgram(mProgram);
//here I give the new position
GLES20.glUniformMatrix4fv(matrixHandle, 1,false, translationMatrix, 0);
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_FAN, 0, vertexCount);
GLES20.glDisableVertexAttribArray(positionHandle);
}
public void moveX(float x)
//moves the Obstacle on the x axies
{
this.xOffset+=x;
Matrix.translateM(translationMatrix, 0, x, 0, 0);
}
public void moveY(float y)
//moves the Obstacle on the y axies
{
this.yOffset+=y;
Matrix.translateM(translationMatrix, 0, 0, y, 0);
}
}
我还可以向您展示我的渲染器类
package com.example.jump;
import java.util.LinkedList;
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;
import android.opengl.GLES20;
import android.opengl.GLSurfaceView;
public class GameRenderer implements GLSurfaceView.Renderer,GameVisualisation {
private LinkedList<ObstacleGL> obstacleList=new LinkedList<ObstacleGL>();
private LinkedList<Obstacle> obstacleQueue= new LinkedList<Obstacle>();
//Renderer Methoden
@Override
public void onDrawFrame(GL10 gl) {
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
createNewObstacles();
for (int i = 0; i < obstacleList.size(); i++) {
obstacleList.get(i).draw();
}
}
public static int loadShader(int type, String shadercode)
{
int shader=GLES20.glCreateShader(type);
GLES20.glShaderSource(shader, shadercode);
GLES20.glCompileShader(shader);
return shader;
}
private void createNewObstacles() {
while(!obstacleQueue.isEmpty()){
Obstacle obs=obstacleQueue.poll();
obstacleList.add(new ObstacleGL(obs.id,(float)obs.xPosition,(float)obs.yPosition,(float)obs.height,(float)obs.width));
}
}
@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
GLES20.glViewport(0, 0, width, height);
}
@Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
GLES20.glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
ObstacleGL.initialize();
}
//more gamerelated stuff is happening here
}
所以我自己让它工作.问题似乎是他不接受 3 号浮点数组或 vec4 制服。解决方案是将 alpha 通道添加到我的颜色数组中。
我替换了
private static float[] color={0.33f,1,0.33f};
跟
private static float[] color={0.33f,1,0.33f,1};