[ADD] you can now manually define wether a texture should be clipped if the value is 0

src/core/graphicsEngine/WGETexture.h

@@ -118,6 +118,13 @@ public:
      */
     WPropDouble alpha() const;
 
+    /**
+     * Clip the values assumed to be zero.
+     *
+     * \return true to clip.
+     */
+    WPropBool clipZero() const;
+
     /**
      * Returns the threshold property. The property can be changed. A change affects all colormaps using this texture.
      *
@@ -348,6 +355,11 @@ private:
      */
     WPropDouble m_alpha;
 
+    /**
+     * If set to true, zero values are clipped by making them transparent
+     */
+    WPropBool m_clipZero;
+
     /**
      * Threshold for clipping areas.
      */
@@ -459,6 +471,8 @@ void WGETexture< TextureType >::setupProperties( double scale, double min )
     m_alpha->setMin( 0.0 );
     m_alpha->setMax( 1.0 );
 
+    m_clipZero = m_properties->addProperty( "Enable Zero Clip", "If enabled, zero values are clipped.", true );
+
     m_thresholdEnabled = m_properties->addProperty( "Enable Threshold",
                                                     "If enabled, threshold based clipping is used. If not, threshold is ignored.", false );
 
@@ -546,6 +560,12 @@ inline WPropDouble WGETexture< TextureType >::alpha() const
     return m_alpha;
 }
 
+template < typename TextureType >
+inline WPropBool WGETexture< TextureType >::clipZero() const
+{
+    return m_clipZero;
+}
+
 template < typename TextureType >
 inline WPropDouble WGETexture< TextureType >::thresholdLower() const
 {
@@ -616,6 +636,7 @@ void  WGETexture< TextureType >::applyUniforms( std::string prefix, osg::StateSe
     states->addUniform( new WGEPropertyUniform< WPropDouble >( prefix + "Min", minimum() ) );
     states->addUniform( new WGEPropertyUniform< WPropDouble >( prefix + "Scale", scale() ) );
     states->addUniform( new WGEPropertyUniform< WPropDouble >( prefix + "Alpha", alpha() ) );
+    states->addUniform( new WGEPropertyUniform< WPropBool >( prefix + "ClipZeroEnabled", clipZero() ) );
     states->addUniform( new WGEPropertyUniform< WPropBool >( prefix + "ThresholdEnabled", thresholdEnabled() ) );
     states->addUniform( new WGEPropertyUniform< WPropDouble >( prefix + "ThresholdLower", thresholdLower() ) );
     states->addUniform( new WGEPropertyUniform< WPropDouble >( prefix + "ThresholdUpper", thresholdUpper() ) );

src/core/graphicsEngine/shaders/shaders/WGEColorMapsImproved.glsl

@@ -436,8 +436,9 @@ vec4 atlas( in float value )
  *
  * \return this color gets mixed using alpha value with the new colormap color
  * \param value the value to map, <b>scaled</b>
- * \param minV the minimum of the original value
+ * \param minV the minimum of the original value *
  * \param scaleV the scaler used to downscale the original value to [0-1]
+ * \param clipZeroEnabled if true, zero values get clipped; based on descaled value.
  * \param thresholdVLower a threshold in original space (you need to downscale it to [0-1] if you want to use it to scaled values.
  * \param thresholdVUpper a threshold in original space (you need to downscale it to [0-1] if you want to use it to scaled values.
  * \param thresholdEnabled a flag denoting whether threshold-based clipping should be done or not
@@ -447,6 +448,7 @@ vec4 atlas( in float value )
  * \param colormap the colormap index to use
  */
 vec4 colormap( in vec4 value, float minV, float scaleV,
+               bool clipZeroEnabled,
                float thresholdVLower, float thresholdVUpper, bool thresholdEnabled,
                vec2  window, bool windowEnabled,
                float alpha, int colormap, bool active )
@@ -483,7 +485,7 @@ vec4 colormap( in vec4 value, float minV, float scaleV,
     float isNotBorder = float( value.a >= 0.75 );
 
     // make "zero" values transarent
-    float clip = clipZero( valueWindowedOriginal.r, minV );
+    float clip = max( float( !clipZeroEnabled ), clipZero( valueWindowedOriginal.r, minV ) );
 
     // use threshold to clip away fragments.
     // NOTE: thresholding is applied to the original interval in valueDescaled, NOT the window interval

src/core/graphicsEngine/shaders/shaders/WGEColormapping-uniforms.glsl

@@ -43,6 +43,9 @@ uniform float u_colormap0Scale = 1;
 //!< The alpha value for this colormap. Is in [0,1].
 uniform float u_colormap0Alpha;
 
+//!< Flag denoting whether to clip the zero value.
+uniform bool u_colormap0ClipZeroEnabled = false;
+
 //!< The threshold value for this colormap. Is in [Min,Scale+Min]
 uniform float u_colormap0ThresholdLower;
 
@@ -85,6 +88,9 @@ uniform float u_colormap1Scale = 1;
 //!< The alpha value for this colormap. Is in [0,1].
 uniform float u_colormap1Alpha;
 
+//!< Flag denoting whether to clip the zero value.
+uniform bool u_colormap1ClipZeroEnabled = false;
+
 //!< The threshold value for this colormap. Is in [Min,Scale+Min]
 uniform float u_colormap1ThresholdLower;
 
@@ -127,6 +133,9 @@ uniform float u_colormap2Scale = 1;
 //!< The alpha value for this colormap. Is in [0,1].
 uniform float u_colormap2Alpha;
 
+//!< Flag denoting whether to clip the zero value.
+uniform bool u_colormap2ClipZeroEnabled = false;
+
 //!< The threshold value for this colormap. Is in [Min,Scale+Min]
 uniform float u_colormap2ThresholdLower;
 
@@ -169,6 +178,9 @@ uniform float u_colormap3Scale = 1;
 //!< The alpha value for this colormap. Is in [0,1].
 uniform float u_colormap3Alpha;
 
+//!< Flag denoting whether to clip the zero value.
+uniform bool u_colormap3ClipZeroEnabled = false;
+
 //!< The threshold value for this colormap. Is in [Min,Scale+Min]
 uniform float u_colormap3ThresholdLower;
 
@@ -211,6 +223,9 @@ uniform float u_colormap4Scale = 1;
 //!< The alpha value for this colormap. Is in [0,1].
 uniform float u_colormap4Alpha;
 
+//!< Flag denoting whether to clip the zero value.
+uniform bool u_colormap4ClipZeroEnabled = false;
+
 //!< The threshold value for this colormap. Is in [Min,Scale+Min]
 uniform float u_colormap4ThresholdLower;
 
@@ -253,6 +268,9 @@ uniform float u_colormap5Scale = 1;
 //!< The alpha value for this colormap. Is in [0,1].
 uniform float u_colormap5Alpha;
 
+//!< Flag denoting whether to clip the zero value.
+uniform bool u_colormap5ClipZeroEnabled = false;
+
 //!< The threshold value for this colormap. Is in [Min,Scale+Min]
 uniform float u_colormap5ThresholdLower;
 
@@ -295,6 +313,9 @@ uniform float u_colormap6Scale = 1;
 //!< The alpha value for this colormap. Is in [0,1].
 uniform float u_colormap6Alpha;
 
+//!< Flag denoting whether to clip the zero value.
+uniform bool u_colormap6ClipZeroEnabled = false;
+
 //!< The threshold value for this colormap. Is in [Min,Scale+Min]
 uniform float u_colormap6ThresholdLower;
 
@@ -337,6 +358,9 @@ uniform float u_colormap7Scale = 1;
 //!< The alpha value for this colormap. Is in [0,1].
 uniform float u_colormap7Alpha;
 
+//!< Flag denoting whether to clip the zero value.
+uniform bool u_colormap7ClipZeroEnabled = false;
+
 //!< The threshold value for this colormap. Is in [Min,Scale+Min]
 uniform float u_colormap7ThresholdLower;