mixtureShader/mixtureShader.cpp

//-
// ===========================================================================
// Copyright 2015 Autodesk, Inc.  All rights reserved.
//
// Use of this software is subject to the terms of the Autodesk license
// agreement provided at the time of installation or download, or which
// otherwise accompanies this software in either electronic or hard copy form.
// ===========================================================================
//+

#include <maya/MPxNode.h>
#include <maya/MIOStream.h>
#include <maya/MString.h>
#include <maya/MTypeId.h>
#include <maya/MPlug.h>
#include <maya/MDataBlock.h>
#include <maya/MDataHandle.h>
#include <maya/MFnNumericAttribute.h>
#include <maya/MFloatVector.h>
#include <maya/MFnPlugin.h>
#include <maya/MDrawRegistry.h>
#include <maya/MPxShadingNodeOverride.h>
#include <maya/MViewport2Renderer.h>
#include <maya/MFragmentManager.h>

//
// DESCRIPTION:
// Produces dependency graph node MixtureNode
 
// This node is an example of evaluating multiple inputs and produces a resulting color.
 
// The inputs for this node are two colors and two masks, where each color has a corresponding mask 
// associated with it and the result color is the mixture of both colors with masks.
 
// The output attribute of the MixtureNode node is called "outColor". It is a 3 float value that represents 
// the resulting color mixture based on the mask values. To use this shader, create a MixtureNode and 
// connect its output to an input of a surface/shader node such as Color.
// 

//
// Node declaration
class MixtureNode : public MPxNode
{
    public:
                    MixtureNode();
            ~MixtureNode() override;

    MStatus compute( const MPlug&, MDataBlock& ) override;
    void    postConstructor() override;

    static  void *  creator();
    static  MStatus initialize();

    // Id tag for use with binary file format
    static  MTypeId id;

    private:

    // Input attributes
    static MObject aColor1;                 // 1st Input color
    static MObject aColor2;                 // 2nd Input color
    static MObject aAlphaInput1;            // Input Alpha's for 1st color
    static MObject aAlphaInput2;            // Input Alpha's for 2nd color

    // Output attributes
    static MObject aOutColor;               // Output color
};

//
// Override declaration
class MixtureNodeOverride : public MHWRender::MPxShadingNodeOverride
{
public:
    static MHWRender::MPxShadingNodeOverride* creator(const MObject& obj);

    ~MixtureNodeOverride() override;

    MHWRender::DrawAPI supportedDrawAPIs() const override;

    MString fragmentName() const override;

private:
    MixtureNodeOverride(const MObject& obj);

    MString fFragmentName;
};

//
// Node definition
MTypeId MixtureNode::id( 0x81007 );

// Attributes
MObject MixtureNode::aColor1;
MObject MixtureNode::aColor2;
MObject MixtureNode::aAlphaInput1;
MObject MixtureNode::aAlphaInput2;
MObject MixtureNode::aOutColor;

#define MAKE_INPUT(attr)                                \
     CHECK_MSTATUS ( attr.setKeyable(true) );           \
     CHECK_MSTATUS ( attr.setStorable(true) );          \
     CHECK_MSTATUS ( attr.setReadable(true) ) ;         \
     CHECK_MSTATUS ( attr.setWritable(true) );

#define MAKE_OUTPUT(attr)                               \
     CHECK_MSTATUS ( attr.setKeyable(false) ) ;         \
     CHECK_MSTATUS ( attr.setStorable(false) );         \
     CHECK_MSTATUS ( attr.setReadable(true) ) ;         \
     CHECK_MSTATUS ( attr.setWritable(false) );

//
// DESCRIPTION:
void MixtureNode::postConstructor( )
{
    setMPSafe(true);
}

//
// DESCRIPTION:
MixtureNode::MixtureNode()
{
}

//
// DESCRIPTION:
MixtureNode::~MixtureNode()
{
}

//
// DESCRIPTION:
void* MixtureNode::creator()
{
    return new MixtureNode();
}


//
// DESCRIPTION:
MStatus MixtureNode::initialize()
{
    MFnNumericAttribute nAttr;

    // Input attributes

    aColor1 = nAttr.createColor( "color1", "c1" );
    MAKE_INPUT(nAttr);
     CHECK_MSTATUS ( nAttr.setDefault(0.0f, 1.0f, 0.0f) );      // Green

    aColor2 = nAttr.createColor( "color2", "c2" );
    MAKE_INPUT(nAttr);
     CHECK_MSTATUS ( nAttr.setDefault(0.0f, 0.0f, 1.0f) );      // Blue

    aAlphaInput1= nAttr.createColor( "mask1", "m1" );
    MAKE_INPUT(nAttr);
     CHECK_MSTATUS ( nAttr.setDefault(.5f, .5f, .5f) );

    aAlphaInput2= nAttr.createColor( "mask2", "m2" );
    MAKE_INPUT(nAttr);
     CHECK_MSTATUS ( nAttr.setDefault(.5f, .5f, .5f) );

    // Output attributes

    aOutColor  = nAttr.createColor( "outColor", "oc" );
    MAKE_OUTPUT(nAttr);

    //  Add attributes to the node database.
     CHECK_MSTATUS ( addAttribute(aColor1) );
     CHECK_MSTATUS ( addAttribute(aColor2) );
     CHECK_MSTATUS ( addAttribute(aAlphaInput1) );
     CHECK_MSTATUS ( addAttribute(aAlphaInput2) );
     CHECK_MSTATUS ( addAttribute(aOutColor) );

    // All input affect the output color
     CHECK_MSTATUS ( attributeAffects(aColor1, aOutColor) );
     CHECK_MSTATUS ( attributeAffects(aColor2, aOutColor) );
     CHECK_MSTATUS ( attributeAffects(aAlphaInput1, aOutColor) );
     CHECK_MSTATUS ( attributeAffects(aAlphaInput2, aOutColor) );

    return MS::kSuccess;
}

//
// DESCRIPTION:
MStatus MixtureNode::compute(const MPlug& plug, MDataBlock& block )
{
    if ((plug != aOutColor) && (plug.parent() != aOutColor))
        return MS::kUnknownParameter;

    MFloatVector color1 = block.inputValue( aColor1 ).asFloatVector();
    MFloatVector color2 = block.inputValue( aColor2 ).asFloatVector();
    MFloatVector mask1  = block.inputValue( aAlphaInput1 ).asFloatVector();
    MFloatVector mask2  = block.inputValue( aAlphaInput2 ).asFloatVector();

    // Mask1 applied to color1, mask2 applied to color2
    color1[0] *= mask1[0]; color1[1] *= mask1[1]; color1[2] *= mask1[2];
    color2[0] *= mask2[0]; color2[1] *= mask2[1]; color2[2] *= mask2[2];

    // set ouput color attribute
    MDataHandle outColorHandle = block.outputValue( aOutColor );
    MFloatVector& outColor = outColorHandle.asFloatVector();
    outColor = color1 + color2;
    outColorHandle.setClean();

    return MS::kSuccess;
}

//
// Override definition
MHWRender::MPxShadingNodeOverride* MixtureNodeOverride::creator(
    const MObject& obj)
{
    return new MixtureNodeOverride(obj);
}

MixtureNodeOverride::MixtureNodeOverride(const MObject& obj)
: MPxShadingNodeOverride(obj)
, fFragmentName("")
{
    // Define fragments needed for VP2 version of shader, this could also be
    // defined in a separate XML file
    //
    // Define the input and output parameter names to match the input and
    // output attribute names so that the values are automatically populated
    // on the shader.
    static const MString sFragmentName("mixtureNodePluginFragment");
    static const char* sFragmentBody =
        "<fragment uiName=\"mixtureNodePluginFragment\" name=\"mixtureNodePluginFragment\" type=\"plumbing\" class=\"ShadeFragment\" version=\"1.0\">"
        "   <description><![CDATA[Mixture utility fragment]]></description>"
        "   <properties>"
        "       <float3 name=\"color1\" />"
        "       <float3 name=\"color2\" />"
        "       <float3 name=\"mask1\" />"
        "       <float3 name=\"mask2\" />"
        "   </properties>"
        "   <values>"
        "       <float3 name=\"color1\" value=\"0.0,1.0,0.0\" />"
        "       <float3 name=\"color2\" value=\"0.0,0.0,1.0\" />"
        "       <float3 name=\"mask1\" value=\"0.5,0.5,0.5\" />"
        "       <float3 name=\"mask2\" value=\"0.5,0.5,0.5\" />"
        "   </values>"
        "   <outputs>"
        "       <float3 name=\"outColor\" />"
        "   </outputs>"
        "   <implementation>"
        "   <implementation render=\"OGSRenderer\" language=\"Cg\" lang_version=\"2.1\">"
        "       <function_name val=\"mixtureNodePluginFragment\" />"
        "       <source><![CDATA["
        "float3 mixtureNodePluginFragment(float3 color1, float3 color2, float3 mask1, float3 mask2) \n"
        "{ \n"
        "   return mask1*color1 + mask2*color2; \n"
        "} \n]]>"
        "       </source>"
        "   </implementation>"
        "   <implementation render=\"OGSRenderer\" language=\"HLSL\" lang_version=\"11.0\">"
        "       <function_name val=\"mixtureNodePluginFragment\" />"
        "       <source><![CDATA["
        "float3 mixtureNodePluginFragment(float3 color1, float3 color2, float3 mask1, float3 mask2) \n"
        "{ \n"
        "   return mask1*color1 + mask2*color2; \n"
        "} \n]]>"
        "       </source>"
        "   </implementation>"
        "   <implementation render=\"OGSRenderer\" language=\"GLSL\" lang_version=\"3.0\">"
        "       <function_name val=\"mixtureNodePluginFragment\" />"
        "       <source><![CDATA["
        "vec3 mixtureNodePluginFragment(vec3 color1, vec3 color2, vec3 mask1, vec3 mask2) \n"
        "{ \n"
        "   return mask1*color1 + mask2*color2; \n"
        "} \n]]>"
        "       </source>"
        "   </implementation>"
        "   </implementation>"
        "</fragment>";

    // Register fragments with the manager if needed
    MHWRender::MRenderer* theRenderer = MHWRender::MRenderer::theRenderer();
    if (theRenderer)
    {
        MHWRender::MFragmentManager* fragmentMgr =
            theRenderer->getFragmentManager();
        if (fragmentMgr)
        {
            // Add fragments if needed
            bool fragAdded = fragmentMgr->hasFragment(sFragmentName);
            if (!fragAdded)
            {
                fragAdded = (sFragmentName == fragmentMgr->addShadeFragmentFromBuffer(sFragmentBody, false));
            }

            // Use the fragment on successful add
            if (fragAdded)
            {
                fFragmentName = sFragmentName;
            }
        }
    }
}

MixtureNodeOverride::~MixtureNodeOverride()
{
}

MHWRender::DrawAPI MixtureNodeOverride::supportedDrawAPIs() const
{
    return MHWRender::kOpenGL | MHWRender::kDirectX11 | MHWRender::kOpenGLCoreProfile;
}

MString MixtureNodeOverride::fragmentName() const
{
    return fFragmentName;
}

//
// Plugin setup
static const MString sRegistrantId("mixtureShaderPlugin");

MStatus initializePlugin( MObject obj )
{
   const MString UserClassify( "utility/color:drawdb/shader/operation/mixture" );

   MFnPlugin plugin( obj, PLUGIN_COMPANY, "4.5", "Any");
    CHECK_MSTATUS ( plugin.registerNode( "mixture", MixtureNode::id,
                         MixtureNode::creator, MixtureNode::initialize,
                         MPxNode::kDependNode, &UserClassify ) );

    CHECK_MSTATUS(
        MHWRender::MDrawRegistry::registerShadingNodeOverrideCreator(
            "drawdb/shader/operation/mixture",
            sRegistrantId,
            MixtureNodeOverride::creator));

   return MS::kSuccess;
}

MStatus uninitializePlugin( MObject obj )
{
   MFnPlugin plugin( obj );
    CHECK_MSTATUS ( plugin.deregisterNode( MixtureNode::id ) );

    CHECK_MSTATUS(
        MHWRender::MDrawRegistry::deregisterShadingNodeOverrideCreator(
            "drawdb/shader/operation/mixture",
            sRegistrantId));

   return MS::kSuccess;
}