## ShaderDef

Object Hierarchy | Related C++ Class: ShaderDef

### Inheritance

SIObject

ShaderDef

### Introduced

v9.0 (2011)

### Description

A shader definition is similar to a preset in that it stores a snapshot of a shader, often in a file on disk. However, a traditional Softimage .preset file is a binary file built from a SPDL, whereas a shader definition can be created and/or modified in several ways, including via a self-installing plug-in, a special XML file saved on disk (.xsishaderdef), or by coding on the fly.
To create a self-installing, plug-in based shader definition you need to implement the Define and DefineInfo callbacks. For more information, see Custom Shaders.
To create a shader definition on the fly, you can use XSIFactory.CreateShaderDef and then populate the definition using the returned ShaderDef object.
Saving shader definitions to a .xsishaderdef file is the most reliable way to manage shader versions. You can then use the ReplaceShadersDefinition command to upgrade a specific list of shaders to a new shader definition.
To get a list of all shader definitions in the current session of Softimage, use the XSIApplication.ShaderDefinitions property. You can also access a specific shader definition by ProgID by using the XSIApplication.GetShaderDef method.

### Methods

AddRendererDef | AddShaderFamily | GetRendererDefByName | IsClassOf
IsEqualTo | IsShaderFamily | RemoveRendererDef |

### Properties

Application | Attributes | Categories | Category
DefinitionPath | DisplayName | FullName | Help
InputParamDefs | Name | NestedObjects | Origin
OriginPath | OutputParamDefs | PPGLayout | Parent
Parsed | Parser | ParserBased | Plugin
PluginBased | PluginFilename | PrimaryShaderFamily | ProgID
RenderTreeLayout | RendererDefs | ShaderFamilies | ShaderInstanceCount
ShaderInstances | ShaderballOpts | Type |

### Examples

#### 1. Python Example

    from win32com.client import constants as si
    app = Application
    app.NewScene("", 0)
    #
    #       SETUP
    #
    # Create a ShaderDef from the factory
    oShaderDef = XSIFactory.CreateShaderDef("NoParser", "Nunce", 1, 0)
    # On-the-fly shader definitions won't show up in the preset manager
    # but just in case this definition eventually gets saved to file
    oShaderDef.Category = "Test Shaders"
    # Add the basic Texture family
    oShaderDef.AddShaderFamily(si.siShaderFamilyTexture)
    #
    #       PARAMETERS
    #
    # Create one set of parameter definition options for all
    oPDefOptions = XSIFactory.CreateShaderParamDefOptions()
    oPDefOptions.SetTexturable(True) # make it a port on the shader node
    # Get the ShaderParamDefContainers for both inputs and outputs. The
    # new parameter definitions will be added to these objects
    oInputPDefs = oShaderDef.InputParamDefs
    oOutputPDefs = oShaderDef.OutputParamDefs
    # Add color, scalar, and boolean ShaderParamDefs as inputs
    oInputPDefs.AddParamDef("in_color", si.siShaderDataTypeColor4 , oPDefOptions)
    oInputPDefs.AddParamDef("in_scalar", si.siShaderDataTypeScalar , oPDefOptions)
    oInputPDefs.AddParamDef("in_boolean", si.siShaderDataTypeBoolean , oPDefOptions)
    # Output a color
    oOutputPDefs.AddParamDef("out", si.siShaderDataTypeColor4, oPDefOptions)
    # Set up a Renderer
    oRendererDef = oShaderDef.AddRendererDef("mental ray")
    oRendererDef.SymbolName = "sib_attribute_boolean"
    oRendererDef.CodePath = "{LIBS}/sibase.{EXT}"
    oRendererOpts = oRendererDef.RendererOptions
    oRendererOpts.Set("version", 1)
    #
    #       INSTANTIATION
    #
    # Generate a preset and connect it to a cone
    app.CreatePrim("Cone", "MeshSurface")
    app.CreateShaderFromProgID("NoParser.Nunce.1.0",
            "Sources.Materials.DefaultLib.Scene_Material")
    app.SIConnectShaderToCnxPoint("Sources.Materials.DefaultLib.Scene_Material.Nunce.out",
            "Sources.Materials.DefaultLib.Scene_Material.volume", False)
    # Open the Render Tree with the cone selected to see it
    # Open the Synoptic viewer
    app.OpenView("Render Tree")

#### 2. JScript Example

    //
    //      This example demonstrates how to instantiate and connect a shader
    //      definition, then how to get the shader definition from the system
    //      and use it to find its instance (shader)
    //
    app = Application;
    app.NewScene("", false);
    var sProgID = "Softimage.material-moviescreen.1.0";
    LogInstances(sProgID);
    CreateShaderFromProgID(sProgID, "Sources.Materials.DefaultLib.Scene_Material");
    LogInstances(sProgID);
    // INFO : # of instances on Flat Light: 1
    // INFO : Found shader instance: Shader
    // INFO : Shader container: null
    // Set up a torus and a disc and connect the shader to both
    var obj1 = CreatePrim("Torus", "MeshSurface");
    SIConnectShaderToCnxPoint("Sources.Materials.DefaultLib.Scene_Material.Flat_Light.out",
            "Sources.Materials.DefaultLib.Scene_Material.Phong.reflectivity", false);
    SIConnectShaderToCnxPoint("Sources.Materials.DefaultLib.Scene_Material.Flat_Light.out",
            "Sources.Materials.DefaultLib.Scene_Material.Phong.radiance", false);
    var obj2 = CreatePrim("Disc", "MeshSurface");
    RemoveShaderFromCnxPoint("Sources.Materials.DefaultLib.Scene_Material.Flat_Light.out",
            "Sources.Materials.DefaultLib.Scene_Material.Phong.reflectivity", false);
    SIConnectShaderToCnxPoint("Sources.Materials.DefaultLib.Scene_Material.Flat_Light.out",
            "Sources.Materials.DefaultLib.Scene_Material.Phong.reflectivity", false);
    LogInstances(sProgID);
    // INFO : # of instances on Flat Light: 2
    // INFO : Found shader instance: Shader
    // INFO : Shader container: null
    // INFO : Found shader instance: Flat_Light
    // INFO : Shader container: Sources.Materials.DefaultLib.Scene_Material
    // Convenience function that will be called before and after
    // instantiating and after connecting the shader
    function LogInstances( in_name )
    {
            var oShaderDef = app.ShaderDefinitions(in_name);
            app.LogMessage("# of instances on "+oShaderDef.DisplayName+": "+oShaderDef.ShaderInstanceCount);
            if (oShaderDef.ShaderInstanceCount) {
                    for (var i=0; i<oShaderDef.ShaderInstanceCount; i++) {
                            var oShader = oShaderDef.ShaderInstances(i);
                            app.LogMessage("Found shader instance: "+oShader.Name);
                            app.LogMessage("Shader container: "+oShader.GetShaderContainer());
                    }
            }
    }

### See Also

XSIApplication.GetShaderDef XSIFactory.CreateShaderDef Shader.ShaderDef XSIFactory.RemoveShaderDef Shader callbacks Custom Shaders Shader Definition examples installed with Softimage Shader Parser examples installed with Softimage