[raster] Add note and docs for psuedocolor 'clip' option

python/core/raster/qgscolorrampshader.sip

@@ -65,6 +65,14 @@ class QgsColorRampShader : QgsRasterShaderFunction
 
     void legendSymbologyItems( QList< QPair< QString, QColor > >& symbolItems ) const;
 
+    /** Sets whether the shader should not render values out of range.
+     * @param clip set to true to clip values which are out of range.
+     * @see clip()
+     */
     void setClip( bool clip );
+
+    /** Returns whether the shader will clip values which are out of range.
+     * @see setClip()
+     */
     bool clip() const;
 };

src/core/raster/qgscolorrampshader.h

@@ -93,7 +93,15 @@ class CORE_EXPORT QgsColorRampShader : public QgsRasterShaderFunction
 
     void legendSymbologyItems( QList< QPair< QString, QColor > >& symbolItems ) const override;
 
+    /** Sets whether the shader should not render values out of range.
+     * @param clip set to true to clip values which are out of range.
+     * @see clip()
+     */
     void setClip( bool clip ) { mClip = clip; }
+
+    /** Returns whether the shader will clip values which are out of range.
+     * @see setClip()
+     */
     bool clip() const { return mClip; }
 
   private:

src/ui/qgssinglebandpseudocolorrendererwidgetbase.ui

@@ -177,8 +177,11 @@
      </item>
      <item>
       <widget class="QCheckBox" name="mClipCheckBox">
+       <property name="toolTip">
+        <string>If checked, any pixels with a value out of range will not be rendered</string>
+       </property>
        <property name="text">
-        <string>Clip</string>
+        <string>Clip raster values which are out of range</string>
        </property>
       </widget>
      </item>