Semantics and annotations supported by the dx11Shader and glslShader plug-ins in Viewport 2.0, Continued

vec4 (glslShader)

HWS_PrimitiveCountPerInstance

Corresponds to: MUniformParameter::kSemanticHWSPrimitiveCountPerInstance.

HWS_FaceLevel

Corresponds to: MUniformParameter::kSemanticHWSFaceLevel.

HWS_VertexLevel

Corresponds to: MUniformParameter::kSemanticHWSVertexLevel.

HWS_InstancedDraw

Corresponds to: MUniformParameter::kSemanticHWSInstancedDraw.

texture_mipmaplevels

The dx11Shader allows for you to control the number of mip-map levels that should be loaded or generated, either at the technique or texture description level.

Use this annotation with your technique definition to specify the mip map levels that should be generated when loading textures while using this technique. The following values are valid.

• <val> = 0: generates all mip map levels for affected textures. If there are any existing mip maps in the textures, then they will be loaded. This allows, for example, the loading of pre-calculated mip maps for DDS textures.

• <val> = 1-10 : only generates mipmaps up to the specified level.

To reduce texture memory, the default value for the dx11Shader plug-in is set to 1, so that only the first mip map level (<val>=1) is loaded / computed.

It is also possible to enforce this on a per texture basis to explicitly reduce memory usage.

Sample implementation as follows:

technique11 T0
< 
    bool overridesDrawState = false;
    int isTransparent = 0;
    int texture_mipmaplevels = <val>;
>

Can be combined with the parameter annotation mipmaplevels, in which case the latter takes precedence. See Texture specific parameter annotations.

(glslShader)

Specifies if this technique should be rendered in semi-transparency mode.

"Opaque" : no transparency (default)

"Transparent" : transparency is enabled.

Corresponds to MPxShaderOverride::isTransparent().

Specifies if this technique should follow Maya's transparent object rendering or is self-managed (multi-passes).

"false" : does not override state (default value)

"true" : self-managed

Corresponds to: MPxShaderOverride::overridesDrawState().

Specifies if this technique requires an extra scale factor to be applied to the object space bounding box.

This allows the technique to indicate that the bounding box should be bigger than the base geometry; normally due to effects such as displacement, and to prevent the geometry from being discarded when moved to the edge of the viewport or during selection.

Default value is 1.0.

Corresponds to: MPxShaderOverride::boundingBoxExtraScale().

handlesConsolidatedGeometry

When set to False, specifies that the Consolidate World feature should be disabled on the geometry to which the glslShader is applied.

This annotation is useful when your technique draws displacement, the calculations of which involve the object-space co-ordinates of an object, such as use of the World transformation matrix. Consolidate World moves vertices of multiple objects into a new shared object-space, and maybe therefore cause your plug-in shader to render incorrectly. In this case, you may want to disable Consolidate World.

PrimitiveFilter

Specifies that this pass can handle the rendering of the following components:

• line as fat line (line size > 1)

• point as fat point (point size > 1)

Can be used to handle edge or vertex components during the rendering pass or the selection pass.

Vertex components are rendered as quads instead of single pixels, and edge components, mostly during pre-selection highlighting, are rendered larger, for better visibility.

This is usually achieved by using a geometry shader to convert lines and points to quads.

"fatLine" : this pass can render lines as quads

"fatPoint" : this pass can render points as quads

If there is no pass defined that handles this special case, the default pass that handles the draw context "nonMaterialItemsPass" or "selectionPass" is used.