Package com.openinventor.inventor.nodes

Class SoFragmentShader

java.lang.Object
com.openinventor.inventor.Inventor
com.openinventor.inventor.misc.SoBase
com.openinventor.inventor.fields.SoFieldContainer
com.openinventor.inventor.nodes.SoNode
com.openinventor.inventor.nodes.SoShaderObject
com.openinventor.inventor.nodes.SoFragmentShader
All Implemented Interfaces:
SafeDisposable
public class SoFragmentShader extends SoShaderObject
Node that defines a fragment shader. This node defines a fragment shader.

See SoShaderProgram for general information about using shaders and shader parameters.

See parent class SoShaderObject for details about using the inherited fields.

Notes:

  • Shaders in the scene graph.
    Shader object nodes cannot be inserted directly in a scene graph.
    They must be added to the shaderObject field of an SoShaderProgram node.
  • Predefined GLSL variables.
    Open Inventor uses a compatibility profile context for rendering. So legacy GLSL predefined variables, for example gl_FragColor, can be used in fragment shaders. However, if you use the GLSL "#version" directive in a shader, you should append the keyword "compatibility", for example: "#version 150 compatibility".
  • Transparency.
    To maintain compatibility with Open Inventor's high quality transparency algorithms like SORTED_PIXEL, fragment shaders should not output a color by setting gl_FragColor (or equivalent parameter) directly. Use the GLSL method OivDepthPeelingOutputColor() instead.

    Fragment shaders can access the depthPeeling API using Open Inventor's built-in "include" mechanism as shown below. (Note: In the "oiv_include" statement there must not be any white space in the string "//!oiv_include". The space character shown below is required by a limitation of our documentation tools.) 

     // Fragment shader GLSL code
 
 // !oiv_include <Inventor/oivDepthPeeling_frag.h> 
 
 void main()
 {
     if (OivDepthPeel( gl_FragCoord.xyz )) {
 
         // Compute and set fragment color
         vec4 color = . . .
 
         OivDepthPeelingOutputColor( color );
     }
 }

  • Transparency.
    If a fragment shader makes geometry transparent (sets alpha values < 1), the application should set the SoShaderProgram.generateTransparency field to true. This ensures that Open Inventor knows to apply the correct handling for the current transparency mode.
  • Shadows.
    To integrate with Open Inventor's shadow casting algorithm, fragment shaders should call the GLSL methods OivComputeShadow() and OivGenerateShadowMap(). Please see SoShadowGroup for example code.

File format/default:

FragmentShader {

    sourceProgram ""
    sourceType FILENAME
    isActive true
    parameter NULL
}

See Also:

  • Constructor Details

    • SoFragmentShader

      public SoFragmentShader()
      Constructor.

  • Method Details

    • isSupported

      public static boolean isSupported(SoShaderObject.SourceTypes sourceType)
      Calls isSupported(sourceType, (com.openinventor.inventor.misc.SoState)null).

    • isSupported

      public static boolean isSupported(SoShaderObject.SourceTypes sourceType, SoState state)
      Indicates if fragment shaders in the specified language are supported by your graphics board. When using a debug build of Open Inventor, some "no context available" warning messages may be generated. You can ignore them or see SoGLExtension for an example of using SoGLContext to avoid them.

    • getMaxTextureImageUnit

      public static int getMaxTextureImageUnit()
      Returns the maximum number of texture image units.