gl: pass bpp as a uniform to shader

bjtangye · Jun 29, 2014 · c535935 · c535935
1 parent d5d5f7a
commit c535935
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Showing 3 changed files with 12 additions and 1 deletion.
diff --git a/src/GLWidgetRenderer.cpp b/src/GLWidgetRenderer.cpp
@@ -398,6 +398,7 @@ bool GLWidgetRendererPrivate::prepareShaderProgram(const VideoFormat &fmt, Color
     a_Position = glGetAttribLocation(program, "a_Position");
     a_TexCoords = glGetAttribLocation(program, "a_TexCoords");
     u_matrix = glGetUniformLocation(program, "u_MVP_matrix");
+    u_bpp = glGetUniformLocation(program, "u_bpp");
     // fragment shader
     u_colorMatrix = glGetUniformLocation(program, "u_colorMatrix");
 #else
@@ -417,12 +418,14 @@ bool GLWidgetRendererPrivate::prepareShaderProgram(const VideoFormat &fmt, Color
     a_Position = shader_program->attributeLocation("a_Position");
     a_TexCoords = shader_program->attributeLocation("a_TexCoords");
     u_matrix = shader_program->uniformLocation("u_MVP_matrix");
+    u_bpp = shader_program->uniformLocation("u_bpp");
     // fragment shader
     u_colorMatrix = shader_program->uniformLocation("u_colorMatrix");
 #endif //NO_QGL_SHADER
     qDebug("glGetAttribLocation(\"a_Position\") = %d\n", a_Position);
     qDebug("glGetAttribLocation(\"a_TexCoords\") = %d\n", a_TexCoords);
     qDebug("glGetUniformLocation(\"u_MVP_matrix\") = %d\n", u_matrix);
+    qDebug("glGetUniformLocation(\"u_bpp\") = %d\n", u_bpp);
     qDebug("glGetUniformLocation(\"u_colorMatrix\") = %d\n", u_colorMatrix);
 
     if (fmt.isRGB())
@@ -900,8 +903,10 @@ void GLWidgetRenderer::drawFrame()
 
 #if NO_QGL_SHADER
         glUniformMatrix4fv(d.u_colorMatrix, 1, GL_FALSE, mat);
+        glUniform1f(d.u_bpp, (GLfloat)d.video_format.bitsPerPixel(0));
 #else
        d.shader_program->setUniformValue(d.u_colorMatrix, d.colorTransform.matrixRef());
+       d.shader_program->setUniformValue(d.u_bpp, (GLfloat)d.video_format.bitsPerPixel(0));
 #endif
         glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
 

diff --git a/src/QtAV/private/GLWidgetRenderer_p.h b/src/QtAV/private/GLWidgetRenderer_p.h
@@ -51,6 +51,7 @@ class Q_AV_EXPORT GLWidgetRendererPrivate : public VideoRendererPrivate
       , a_Position(-1)
       , a_TexCoords(-1)
       , u_matrix(-1)
+      , u_bpp(-1)
       , painter(0)
       , video_format(VideoFormat::Format_Invalid)
     {
@@ -195,6 +196,7 @@ class Q_AV_EXPORT GLWidgetRendererPrivate : public VideoRendererPrivate
     QVector<GLint> u_Texture; //u_TextureN uniform. size is channel count
     GLint u_matrix;
     GLint u_colorMatrix;
+    GLuint u_bpp;
 
     QPainter *painter;
 

diff --git a/src/shaders/yuv_rgb.f.glsl b/src/shaders/yuv_rgb.f.glsl
@@ -34,6 +34,7 @@ uniform sampler2D u_Texture0;
 uniform sampler2D u_Texture1;
 uniform sampler2D u_Texture2;
 varying lowp vec2 v_TexCoords;
+uniform float u_bpp;
 uniform mat4 u_colorMatrix;
 
 //http://en.wikipedia.org/wiki/YUV calculation used
@@ -60,7 +61,7 @@ const mat4 yuv2rgbMatrix = mat4(1, 1, 1, 0,
 // 10, 16bit: http://msdn.microsoft.com/en-us/library/windows/desktop/bb970578%28v=vs.85%29.aspx
 void main()
 {
-#if defined(YUV16BITS_LE_LUMINANCE_ALPHA) || defined(YUV16BITS_BE_LUMINANCE_ALPHA)
+#if 0 //defined(YUV16BITS_LE_LUMINANCE_ALPHA) || defined(YUV16BITS_BE_LUMINANCE_ALPHA)
     // FFmpeg supports 9, 10, 12, 14, 16 bits
 #if defined(YUV9P)
     const float range = 511.0;
@@ -73,6 +74,9 @@ void main()
 #elif defined(YUV16P)
     const float range = 65535.0;
 #endif
+#else
+    //http://stackoverflow.com/questions/22693169/opengl-es-2-0-glsl-compiling-fails-on-osx-when-using-const
+    float range = exp2(u_bpp) - 1.0; // why can not be const?
 #endif //defined(YUV16BITS_LE_LUMINANCE_ALPHA)
     // 10p in little endian: yyyyyyyy yy000000 => (L, L, L, A)
     gl_FragColor = clamp(u_colorMatrix*yuv2rgbMatrix* vec4(