2012-07-21 52 views
1

我想要一个统一的变种添加到我的着色器,这是我的着色器:libGDX:添加均匀VAR

String vertexShader = "attribute vec4 " + ShaderProgram.POSITION_ATTRIBUTE + ";\n" // 
      + "attribute vec4 " + ShaderProgram.COLOR_ATTRIBUTE + ";\n" // 
      + "attribute vec2 " + ShaderProgram.TEXCOORD_ATTRIBUTE + "0;\n" // 
      + "uniform mat4 u_projTrans;\n" // 
      + "varying vec4 v_color;\n" // 
      + "varying vec2 v_texCoords;\n" // 
      + "\n" // 
      + "void main()\n" // 
      + "{\n" // 
      + " v_texCoords = " + ShaderProgram.TEXCOORD_ATTRIBUTE + "0;\n" // 
      + " gl_Position = u_projTrans * " + ShaderProgram.POSITION_ATTRIBUTE + ";\n" // 
      + "}\n"; 
     String fragmentShader = "#ifdef GL_ES\n" // 
      + "#define LOWP lowp\n" // 
      + "precision mediump float;\n" // 
      + "#else\n" // 
      + "#define LOWP \n" // 
      + "#endif\n" // 
      + "varying vec2 v_texCoords;\n" // 
      + "uniform sampler2D u_texture;\n" // 
      + "uniform sampler2D u_texturePalette;\n" // 
      + "void main()\n"// 
      + "{\n" // 
      + " vec4 textureColor = texture2D(u_texture, v_texCoords).rgba;\n" 
      + " vec4 paletteColor = texture2D(u_texturePalette, vec2(textureColor.b,0)).rgba;\n"  
      + " gl_FragColor = paletteColor;\n" // 
      + "}"; 

问题带有

均匀sampler2D u_texturePalette;

ShaderProgram无法识别着色器中的新制服。此外,我已经做到了这一点:

shader = new ShaderProgram(vertexShader, fragmentShader); 
    shader.setUniformi("u_texturePalette", 0); 
    Texture text = new Texture(Gdx.files.internal("./data/palette.png")); 
    text.bind(shader.getUniformLocation("u_texturePalette")); 
    batch = new SpriteBatch(); 
    batch.setShader(shader); 

当我打电话功能shader.hasUniform("u_texturePalette"),它解析为真,但是当我去看看shader.getUniformLocation("u_texturePalette")它解析为-1

这是一个错误? 。任何想法我做得不好?

+0

你肯定着色器编译和链接成功? – Tim 2012-07-21 16:49:32

+0

@Tim着色器编译得很好,但我怎么能看到它的链接好吗? – 2012-07-21 18:37:32

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我对libGDX并不熟悉,但对于OpenGL来说,它就像'glGetProgramiv(program,GL_LINK_STATUS,retVal)'。查看libGDX支持哪种错误检查。 – Tim 2012-07-21 18:59:28

回答

1

着色器代码看起来不错。

一般来说,你做这样的:

shader = new ShaderProgram(vertexShader, fragmentShader); 
Texture text = new Texture(Gdx.files.internal("./data/palette.png")); 
text.bind(0); 
shader.setUniformi("u_texturePalette", 0); 

所以你纹理绑定到活动纹理单元,然后通过setUniformi()传递单元。

getUniformLocation()实际上做不同的东西:https://www.khronos.org/opengles/sdk/docs/man/xhtml/glGetUniformLocation.xml

但是你会碰到一些更多的问题在这里,因为SpriteBatch内部做了一些非常具体的东西与自定义着色器。我建议你的代码看看: https://github.com/libgdx/libgdx/blob/master/gdx/src/com/badlogic/gdx/graphics/g2d/SpriteBatch.java

具体它将把默认的纹理总是在单元0