TextureEffect: Server basics

A TextureEffect is a plug-in server that defines a texture output or gradient input. These can be extended to provide access to any attributes in any packets in the sample vector.

Overview

Effects are used when texturing. A texture evaluates to a percentage or color, and that is applied as an effect, like diffuse color or luminous amount. Some effects can also be used as gradient inputs. Each effect is implemented by a TextureEffect server, providing a way of interpreting one aspect of shading as a simple value. The value can be scalar or RGB, and it can be read from the sample vector and/or written to the sample vector.

Headers

  • ‘’’vector (lx-vector.hpp)’’’

    • ‘’CLxImpl_TextureEffect’’

    • ‘’CLxUser_PacketService’’

  • LXsTFX_CATEGORY – the category of the effect. ‘’NOTE: needs SDK defines’’

The plug-in server class derives from CLxImpl_TextureEffect, and exports the ILxTextureEffect interface.

TextureEffect::Type()

The Type() method returns the base type, scalar or color, plus bits indicating whether the effect can be read, written, or used as a gradient input.

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         unsigned int
 tfx_Type ()                          LXx_OVERRIDE
 {
         return LXi_TFX_SCALAR | LXf_TFX_READ | LXf_TFX_WRITE;
 }

TextureEffect::TypeName()

The TypeName() method returns the type of the value, in this case a percent.

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         const char *
 tfx_TypeName ()                      LXx_OVERRIDE
 {
         return LXs_TYPE_PERCENT;
 }

TextureEffect::Get()

The Get() method reads packets from the sample vector, and outputs a value. Color values write to three sequential locations.

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         LxResult
 tfx_Get (
         ILxUnknownID          sv,
         float                *val,
         void                 *item)  LXx_OVERRIDE
 {
         LXpSampleParms       *sParm = (LXpSampleParms *) packet_svc.FastPacket (sv, sParm_offset);

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         val[0] = sParm->rough;
         return LXe_OK;
 }

TextureEffect::Set()

The Set() method does the reverse. For writable effects it takes an input value and deposits that into the sample vector.

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         LxResult
 tfx_Set (
         ILxUnknownID          sv,
         const float          *val,
         void                 *item)  LXx_OVERRIDE
 {
         LXpSampleParms       *sParm = (LXpSampleParms *) packet_svc.FastPacket (sv, sParm_offset);

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         sParm->rough = val[0];
         return LXe_OK;
 }