OpenGL ES 2.0無法編譯Android着色器

Question

OpenGL ES 2.0中的着色器編譯器出現問題。 每當我嘗試編譯着色器時，它都不會編譯，我也不知道為什么。 我可以創建着色器，編譯會給我錯誤。 這是我的Renderer類的代碼

import android.content.Context;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.util.logging.Logger;

import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;

import util.LoggerConfig;
import util.ShaderHelper;
import util.TextResourceReader;

import static android.opengl.GLES20.*;
import static android.opengl.GLUtils.*;
import static android.opengl.Matrix.*;
import android.opengl.GLSurfaceView.Renderer;
import android.util.Log;

public class ProjekcikRenderer implements Renderer {

    private static final int POSITION_COMPONENT_COUNT = 2;
    private static final int BYTES_PER_FLOAT = 4;
    private final FloatBuffer vertexData;
    private final Context context;
    private int program;
    private static final String U_COLOR = "u_COLOR";
    private int uColorLocation;
    private static final String A_POSITION = "a_Position";
    private int aPositionLocation;
    private static final String TAG = "ProjekcikRenderer";

    public ProjekcikRenderer(Context context){
        this.context = context;
        float[] tableVertices = {
            0f, 0f,
            1f, 1f,
            0f, 1f,

            0f, 0f,
            1f, 0f,
            1, 1f
        };

        vertexData = ByteBuffer
                .allocateDirect(tableVertices.length * BYTES_PER_FLOAT)
                .order(ByteOrder.nativeOrder())
                .asFloatBuffer();

        vertexData.put(tableVertices);
    }

    @Override
    public void onSurfaceCreated(GL10 glUnused, EGLConfig config){
        glClearColor(1.0f, 1.0f, 0.5f, 0.0f);
        String vertexShaderSource = null;
        String fragmentShaderSource = null;
        try{
            vertexShaderSource = TextResourceReader.readTextFileFromResource(context, R.raw.simple_vertex_shader);
            fragmentShaderSource = TextResourceReader.readTextFileFromResource(context, R.raw.simple_fragment_shader);
        } catch (IOException e){
            throw new RuntimeException("IOException", e);
        } catch (Exception e){
            throw new RuntimeException("Other Exception", e);
        }

        //int vertexShader = compileShader(GL_VERTEX_SHADER, vertexShaderSource);
        int vertexShader = glCreateShader(GL_VERTEX_SHADER);
        Log.d(TAG, "CREATING VERTEX SHADER");
        String s = new String(Integer.toString(vertexShader));
        if(vertexShader == 0){
            if(LoggerConfig.ON){
                Log.w(TAG, "Could not create new VERTEX shader");
            }
            return;
        } else {
            if(LoggerConfig.ON){
                Log.w(TAG, s);
            }
        }
        glShaderSource(vertexShader, vertexShaderSource);
        final int[] compileStatus = new int[1];
        glGetShaderiv(vertexShader, GL_COMPILE_STATUS, compileStatus, 0);
        if(LoggerConfig.ON){
            Log.v(TAG, "Results of compiling source:" + "\n" + vertexShaderSource + "\n" + glGetShaderInfoLog(vertexShader));
        }
        if(compileStatus[0] == 0){
            glDeleteShader(vertexShader);
            if(LoggerConfig.ON){
                Log.w(TAG, "Compilation of shader failed");
            }
            return;
        }
        int fragmentShader = compileShader(GL_FRAGMENT_SHADER, fragmentShaderSource);
        program = linkProgram(vertexShader, fragmentShader);

        if(LoggerConfig.ON){
            validateProgram(program);
        }

        glUseProgram(program);

        uColorLocation = glGetUniformLocation(program, U_COLOR);
        aPositionLocation = glGetAttribLocation(program, A_POSITION);
        vertexData.position(0);
        glVertexAttribPointer(aPositionLocation, POSITION_COMPONENT_COUNT, GL_FLOAT, false, 0, vertexData);
        glEnableVertexAttribArray(aPositionLocation);




    }

    @Override
    public void onSurfaceChanged(GL10 glUnused, int width, int height){
        glViewport(0, 0, width, height);
    }

    @Override
    public void onDrawFrame(GL10 glUnused){
        glClear(GL_COLOR_BUFFER_BIT);
        glUniform4f(uColorLocation, 0.0f, 0.0f, 0.0f, 1.0f);
        glDrawArrays(GL_TRIANGLES, 0, 6);
    }

    public static int compileVertexShader(String shaderCode){
        return compileShader(GL_VERTEX_SHADER, shaderCode);
    }

    public static int compileFragmentShader(String shaderCode){
        return compileShader(GL_FRAGMENT_SHADER, shaderCode);
    }

    private static int compileShader(int type, String shaderCode){
        final int shaderObjectId = glCreateShader(type);
        String s = new String(Integer.toString(type));

        if(shaderObjectId == 0){
            if(LoggerConfig.ON){
                Log.w(TAG, "Could not create new shader");
            }
            return 0;
        } else {
            if(LoggerConfig.ON){
                Log.w(TAG, s);
            }
        }
        glShaderSource(shaderObjectId, shaderCode);
        final int[] compileStatus = new int[1];
        glGetShaderiv(shaderObjectId, GL_COMPILE_STATUS, compileStatus, 0);
        if(LoggerConfig.ON){
            Log.v(TAG, "Results of compiling source:" + "\n" + shaderCode + "\n" + glGetShaderInfoLog(shaderObjectId));
        }
        if(compileStatus[0] == 0){
            glDeleteShader(shaderObjectId);
            if(LoggerConfig.ON){
                Log.w(TAG, "Compilation of shader failed");
            }
            return 0;
        }
        return shaderObjectId;
    }

    public static int linkProgram (int vertexShaderId, int fragmentShaderId){
        final int programObjectId = 0;

        glAttachShader(programObjectId, vertexShaderId);
        glAttachShader(programObjectId, fragmentShaderId);
        glLinkProgram(programObjectId);
        if(programObjectId == 0){
            if(LoggerConfig.ON){
                Log.w(TAG, "Could not create new program");
            }
            return 0;
        }
        final int[] linkStatus = new int[1];
        glGetProgramiv(programObjectId, GL_LINK_STATUS, linkStatus, 0);
        if(LoggerConfig.ON){
            Log.v(TAG, "Results of linking program:\n" + glGetProgramInfoLog(programObjectId));
        }
        if(linkStatus[0] == 0){
            glDeleteProgram(programObjectId);
            if(LoggerConfig.ON){
                Log.w(TAG, "Linking of program failed");
            }
            return 0;
        }
        return programObjectId;
    }

    public static boolean validateProgram(int programObjectId){
        glValidateProgram(programObjectId);

        final int[] validateStatus = new int[1];
        glGetProgramiv(programObjectId, GL_VALIDATE_STATUS, validateStatus, 0);
        Log.v(TAG, "Results of validating program: " + validateStatus[0] + "\nLog: " + glGetProgramInfoLog(programObjectId));
        return validateStatus[0] != 0;
    }

}

這是我的vertex着色器

attribute vec4 a_Position;

void main(){
    gl_Position = a_Position;
}

和logs

08-12 09:26:46.350    1281-1281/pl.projekcik D/libEGL﹕ loaded /system/lib/egl/libEGL_mali.so
08-12 09:26:46.350    1281-1281/pl.projekcik D/libEGL﹕ loaded /system/lib/egl/libGLESv1_CM_mali.so
08-12 09:26:46.350    1281-1281/pl.projekcik D/libEGL﹕ loaded /system/lib/egl/libGLESv2_mali.so
08-12 09:26:46.370    1281-1281/pl.projekcik D/OpenGLRenderer﹕ Enabling debug mode 0
08-12 09:26:46.400    1281-1308/pl.projekcik D/ProjekcikRenderer﹕ CREATING VERTEX SHADER
08-12 09:26:46.400    1281-1308/pl.projekcik W/ProjekcikRenderer﹕ 1
08-12 09:26:46.400    1281-1308/pl.projekcik V/ProjekcikRenderer﹕ Results of compiling source:
    attribute vec4 a_Position;
    void main(){
    gl_Position = a_Position;
    }
08-12 09:26:46.400    1281-1308/pl.projekcik W/ProjekcikRenderer﹕ Compilation of shader failed
08-12 09:26:46.430    1281-1283/pl.projekcik D/dalvikvm﹕ GC_CONCURRENT freed 225K, 8% free 6284K/6791K, paused 12ms+5ms, total 44ms

任何幫助將不勝感激。 我正在使用Kevin Brothael的書OpenGL ES 2 for Android ，因為這是我第一次使用OpenGL。

編輯我在帶有一些“ Quad Core GPU”的Prestigio PMP7880D3G上使用Android 4.1.1。 但是幾乎相同的代碼（用於着色器編譯的功能在附加的類ShaderHelper ）在Xperia Z1 Compact上運行的Android 5.0.2上不起作用。

Answer 1

你錯過了一個電話GLES20.glCompileShader(vertexShader)之后您調用glShaderSource()

嘗試在此處修復您的代碼：

glShaderSource(vertexShader, vertexShaderSource);
glCompileShader(vertexShader); // <-- this line is missing.

// Now see if the compilation worked.
int[] compiled = new int[1];
glGetShaderiv(vertexShader, GLES20.GL_COMPILE_STATUS, compiled, 0);

if (compiled[0] == 0)
{
    // Handle errors with shader compilation.
}

這是我用來在OpenGL-ES 2.0中生成程序的代碼存根：

private int loadShader(String strSource, int iType)
    {
        int[] compiled = new int[1];
        int iShader = GLES20.glCreateShader(iType);
        GLES20.glShaderSource(iShader, strSource);
        GLES20.glCompileShader(iShader);
        GLES20.glGetShaderiv(iShader, GLES20.GL_COMPILE_STATUS, compiled, 0);
        if (compiled[0] == 0) {
            Log.d("Load Shader Failed", "Compilation\n" + GLES20.glGetShaderInfoLog(iShader));
            return 0;
        }
        return iShader;
    }

    public int loadProgram(String strVSource, String strFSource)
    {
        int iVShader;
        int iFShader;
        int iProgId;
        int[] link = new int[1];
        iVShader = loadShader(strVSource, GLES20.GL_VERTEX_SHADER);
        if (iVShader == 0)
        {
            Log.d("Load Program", "Vertex Shader Failed");
            return 0;
        }
        iFShader = loadShader(strFSource, GLES20.GL_FRAGMENT_SHADER);
        if(iFShader == 0)
        {
            Log.d("Load Program", "Fragment Shader Failed");
            return 0;
        }

        iProgId = GLES20.glCreateProgram();

        GLES20.glAttachShader(iProgId, iVShader);
        GLES20.glAttachShader(iProgId, iFShader);

        GLES20.glLinkProgram(iProgId);

        GLES20.glGetProgramiv(iProgId, GLES20.GL_LINK_STATUS, link, 0);
        if (link[0] <= 0) {
            Log.d("Load Program", "Linking Failed");
            return 0;
        }
        GLES20.glDeleteShader(iVShader);
        GLES20.glDeleteShader(iFShader);
        return iProgId;
    }

Answer 2

首先，您確定為ES 2.0設置了渲染上下文嗎？ 如果您使用的是GLSurfaceView ，除非有其他要求，否則它將默認為ES 1.1，但此處未包括該部分代碼（盡管它似乎是根據日志正確設置的）。

其次，與桌面OpenGL的GLSL着色器相反，GL ES中的着色器中的變量需要指定精度。 因此，您在其中具有attribute vec4 a_Position; 您需要將其指定為例如attribute highp vec4 a_Position; 。 希望對於此特定的簡單頂點着色器而言，足以編譯。