scripted/pyBrickShader.py

#-
# ===========================================================================
# 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.
# ===========================================================================
#+

import sys
import math
import maya.api.OpenMaya as om
import maya.api.OpenMayaRender as omr

# Produces dependency graph node brickTexture 
# This node is an example of a brick 2d texture.
# The output attribute of the BrickTexture node is called "outColor". To use this shader, create a BrickTexture 
# and connect its output to an input of a surface/shader node such as Color.


def maya_useNewAPI():
    """
    The presence of this function tells Maya that the plugin produces, and
    expects to be passed, objects created using the Maya Python API 2.0.
    """
    pass

def step(t, c):
    if t < c:
        return 0.0
    return 1.0

def smoothstep(t, a, b):
    if t < a:
        return 0.0
    if t > b:
        return 1.0
    t = (t - a)/(b - a)
    return t*t*(3.0 - 2.0*t)

def linearstep(t, a, b):
    if t < a:
        return 0.0
    if t > b:
        return 1.0
    return (t - a)/(b - a)

##
## Node declaration
#######################################################
class brickTextureNode(om.MPxNode):
    # Id tag for use with binary file format
    id = om.MTypeId( 0x8100d )

    # Input attributes
    aColor1 = None
    aColor2 = None
    aBlurFactor = None
    aUVCoord = None
    aFilterSize = None

    # Output attributes
    aOutColor = None

    @staticmethod
    def creator():
        return brickTextureNode()

    @staticmethod
    def initialize():
        nAttr = om.MFnNumericAttribute()

        # Input attributes

        brickTextureNode.aColor1 = nAttr.createColor("brickColor", "bc")
        nAttr.keyable = True
        nAttr.storable = True
        nAttr.readable = True
        nAttr.writable = True
        nAttr.default = (.75, .3, .1)           # Brown

        brickTextureNode.aColor2 = nAttr.createColor("jointColor", "jc")
        nAttr.keyable = True
        nAttr.storable = True
        nAttr.readable = True
        nAttr.writable = True
        nAttr.default = (.75, .75, .75)         # Grey

        brickTextureNode.aBlurFactor = nAttr.create( "blurFactor", "bf", om.MFnNumericData.kFloat)
        nAttr.keyable = True
        nAttr.storable = True
        nAttr.readable = True
        nAttr.writable = True

        # Implicit shading network attributes

        child1 = nAttr.create( "uCoord", "u", om.MFnNumericData.kFloat)
        child2 = nAttr.create( "vCoord", "v", om.MFnNumericData.kFloat)
        brickTextureNode.aUVCoord = nAttr.create( "uvCoord", "uv", child1, child2)
        nAttr.keyable = True
        nAttr.storable = True
        nAttr.readable = True
        nAttr.writable = True
        nAttr.hidden = True

        child1 = nAttr.create( "uvFilterSizeX", "fsx", om.MFnNumericData.kFloat)
        child2 = nAttr.create( "uvFilterSizeY", "fsy", om.MFnNumericData.kFloat)
        brickTextureNode.aFilterSize = nAttr.create("uvFilterSize", "fs", child1, child2)
        nAttr.keyable = True
        nAttr.storable = True
        nAttr.readable = True
        nAttr.writable = True
        nAttr.hidden = True

        # Output attributes
        brickTextureNode.aOutColor = nAttr.createColor("outColor", "oc")
        nAttr.keyable = False
        nAttr.storable = False
        nAttr.readable = True
        nAttr.writable = False

        # Add attributes to the node database.
        om.MPxNode.addAttribute(brickTextureNode.aColor1)
        om.MPxNode.addAttribute(brickTextureNode.aColor2)
        om.MPxNode.addAttribute(brickTextureNode.aBlurFactor)
        om.MPxNode.addAttribute(brickTextureNode.aFilterSize)
        om.MPxNode.addAttribute(brickTextureNode.aUVCoord)

        om.MPxNode.addAttribute(brickTextureNode.aOutColor)

        # All input affect the output color
        om.MPxNode.attributeAffects(brickTextureNode.aColor1,       brickTextureNode.aOutColor)
        om.MPxNode.attributeAffects(brickTextureNode.aColor2,       brickTextureNode.aOutColor)
        om.MPxNode.attributeAffects(brickTextureNode.aBlurFactor,   brickTextureNode.aOutColor)
        om.MPxNode.attributeAffects(brickTextureNode.aFilterSize,   brickTextureNode.aOutColor)
        om.MPxNode.attributeAffects(brickTextureNode.aUVCoord,      brickTextureNode.aOutColor)

    def __init__(self):
        om.MPxNode.__init__(self)

    #######################################################
    ## DESCRIPTION:
    ## This function gets called by Maya to evaluate the texture.
    ##
    ## Get color1 and color2 from the input block.
    ## Get UV coordinates from the input block.
    ## Compute the color of our brick for a given UV coordinate.
    ## Put the result into the output plug.
    #######################################################
    def compute(self, plug, block):
        # outColor or individial R, G, B channel
        if (plug != brickTextureNode.aOutColor) and (plug.parent() != brickTextureNode.aOutColor):
            return None # let Maya handle this attribute

        uv = block.inputValue( brickTextureNode.aUVCoord ).asFloat2()
        surfaceColor1 = block.inputValue( brickTextureNode.aColor1 ).asFloatVector()
        surfaceColor2 = block.inputValue( brickTextureNode.aColor2 ).asFloatVector()

        # normalize the UV coords
        uv[0] -= math.floor(uv[0])
        uv[1] -= math.floor(uv[1])

        borderWidth = 0.1
        brickHeight = 0.4
        brickWidth  = 0.9
        blur = block.inputValue( brickTextureNode.aBlurFactor ).asFloat()

        v1 = borderWidth/2
        v2 = v1 + brickHeight
        v3 = v2 + borderWidth
        v4 = v3 + brickHeight
        u1 = borderWidth/2
        u2 = brickWidth/2
        u3 = u2 + borderWidth
        u4 = u1 + brickWidth

        fs = block.inputValue( brickTextureNode.aFilterSize ).asFloat2()
        du = blur*fs[0]/2.0
        dv = blur*fs[1]/2.0

        t = max(min(linearstep(uv[1], v1 - dv, v1 + dv) - linearstep(uv[1], v2 - dv, v2 + dv), max(linearstep(uv[0], u3 - du, u3 + du), 1 - linearstep(uv[0], u2 - du, u2 + du))), min(linearstep(uv[1], v3 - dv, v3 + dv) - linearstep(uv[1], v4 - dv, v4 + dv), linearstep(uv[0], u1 - du, u1 + du) - linearstep(uv[0], u4 - du, u4 + du)))

        resultColor = t*surfaceColor1 + (1.0 - t)*surfaceColor2

        # set ouput color attribute
        outColorHandle = block.outputValue( brickTextureNode.aOutColor )
        outColorHandle.setMFloatVector( resultColor )
        outColorHandle.setClean()

    def postConstructor(self):
        self.setMPSafe(True)

##
## Override declaration
#######################################################
class brickTextureNodeOverride(omr.MPxShadingNodeOverride):
    @staticmethod
    def creator(obj):
        return brickTextureNodeOverride(obj)

    def __init__(self, obj):
        omr.MPxShadingNodeOverride.__init__(self, obj)

        # Register fragments with the manager if needed
        fragmentMgr = omr.MRenderer.getFragmentManager()
        if fragmentMgr != None:
            if not fragmentMgr.hasFragment("brickTextureNodePluginFragment"):
                fragmentBody = "<fragment uiName=\"brickTextureNodePluginFragment\" name=\"brickTextureNodePluginFragment\" type=\"plumbing\" class=\"ShadeFragment\" version=\"1.0\">"
                fragmentBody += "   <description><![CDATA[Brick procedural texture fragment]]></description>"
                fragmentBody += "   <properties>"
                fragmentBody += "       <float3 name=\"brickColor\" />"
                fragmentBody += "       <float3 name=\"jointColor\" />"
                fragmentBody += "       <float name=\"blurFactor\" />"
                fragmentBody += "       <float2 name=\"uvCoord\" semantic=\"mayaUvCoordSemantic\" flags=\"varyingInputParam\" />"
                fragmentBody += "       <float2 name=\"uvFilterSize\" />"
                fragmentBody += "   </properties>"
                fragmentBody += "   <values>"
                fragmentBody += "       <float3 name=\"brickColor\" value=\"0.75,0.3,0.1\" />"
                fragmentBody += "       <float3 name=\"jointColor\" value=\"0.75,0.75,0.75\" />"
                fragmentBody += "   </values>"
                fragmentBody += "   <outputs>"
                fragmentBody += "       <float3 name=\"outColor\" />"
                fragmentBody += "   </outputs>"
                fragmentBody += "   <implementation>"
                fragmentBody += "   <implementation render=\"OGSRenderer\" language=\"Cg\" lang_version=\"2.1\">"
                fragmentBody += "       <function_name val=\"brickTextureNodePluginFragment\" />"
                fragmentBody += "       <source><![CDATA["
                fragmentBody += "float btnplinearstep(float t, float a, float b) \n"
                fragmentBody += "{ \n"
                fragmentBody += "   if (t < a) return 0.0f; \n"
                fragmentBody += "   if (t > b) return 1.0f; \n"
                fragmentBody += "   return (t - a)/(b - a); \n"
                fragmentBody += "} \n"
                fragmentBody += "float3 brickTextureNodePluginFragment(float3 color1, float3 color2, float blur, float2 uv, float2 fs) \n"
                fragmentBody += "{ \n"
                fragmentBody += "   uv -= floor(uv); \n"
                fragmentBody += "   float v1 = 0.05f; float v2 = 0.45f; float v3 = 0.55f; float v4 = 0.95f; \n"
                fragmentBody += "   float u1 = 0.05f; float u2 = 0.45f; float u3 = 0.55f; float u4 = 0.95f; \n"
                fragmentBody += "   float du = blur*fs.x/2.0f; \n"
                fragmentBody += "   float dv = blur*fs.y/2.0f; \n"
                fragmentBody += "   float t = max( \n"
                fragmentBody += "       min(btnplinearstep(uv.y, v1 - dv, v1 + dv) - btnplinearstep(uv.y, v2 - dv, v2 + dv), \n"
                fragmentBody += "           max(btnplinearstep(uv.x, u3 - du, u3 + du), 1.0f - btnplinearstep(uv.x, u2 - du, u2 + du))), \n"
                fragmentBody += "       min(btnplinearstep(uv.y, v3 - dv, v3 + dv) - btnplinearstep(uv.y, v4 - dv, v4 + dv), \n"
                fragmentBody += "           btnplinearstep(uv.x, u1 - du, u1 + du) - btnplinearstep(uv.x, u4 - du, u4 + du))); \n"
                fragmentBody += "   return t*color1 + (1.0f - t)*color2; \n"
                fragmentBody += "} \n]]>"
                fragmentBody += "       </source>"
                fragmentBody += "   </implementation>"
                fragmentBody += "   <implementation render=\"OGSRenderer\" language=\"HLSL\" lang_version=\"11.0\">"
                fragmentBody += "       <function_name val=\"brickTextureNodePluginFragment\" />"
                fragmentBody += "       <source><![CDATA["
                fragmentBody += "float btnplinearstep(float t, float a, float b) \n"
                fragmentBody += "{ \n"
                fragmentBody += "   if (t < a) return 0.0f; \n"
                fragmentBody += "   if (t > b) return 1.0f; \n"
                fragmentBody += "   return (t - a)/(b - a); \n"
                fragmentBody += "} \n"
                fragmentBody += "float3 brickTextureNodePluginFragment(float3 color1, float3 color2, float blur, float2 uv, float2 fs) \n"
                fragmentBody += "{ \n"
                fragmentBody += "   uv -= floor(uv); \n"
                fragmentBody += "   float v1 = 0.05f; float v2 = 0.45f; float v3 = 0.55f; float v4 = 0.95f; \n"
                fragmentBody += "   float u1 = 0.05f; float u2 = 0.45f; float u3 = 0.55f; float u4 = 0.95f; \n"
                fragmentBody += "   float du = blur*fs.x/2.0f; \n"
                fragmentBody += "   float dv = blur*fs.y/2.0f; \n"
                fragmentBody += "   float t = max( \n"
                fragmentBody += "       min(btnplinearstep(uv.y, v1 - dv, v1 + dv) - btnplinearstep(uv.y, v2 - dv, v2 + dv), \n"
                fragmentBody += "           max(btnplinearstep(uv.x, u3 - du, u3 + du), 1.0f - btnplinearstep(uv.x, u2 - du, u2 + du))), \n"
                fragmentBody += "       min(btnplinearstep(uv.y, v3 - dv, v3 + dv) - btnplinearstep(uv.y, v4 - dv, v4 + dv), \n"
                fragmentBody += "           btnplinearstep(uv.x, u1 - du, u1 + du) - btnplinearstep(uv.x, u4 - du, u4 + du))); \n"
                fragmentBody += "   return t*color1 + (1.0f - t)*color2; \n"
                fragmentBody += "} \n]]>"
                fragmentBody += "       </source>"
                fragmentBody += "   </implementation>"
                fragmentBody += "   <implementation render=\"OGSRenderer\" language=\"GLSL\" lang_version=\"3.0\">"
                fragmentBody += "       <function_name val=\"brickTextureNodePluginFragment\" />"
                fragmentBody += "       <source><![CDATA["
                fragmentBody += "float btnplinearstep(float t, float a, float b) \n"
                fragmentBody += "{ \n"
                fragmentBody += "   if (t < a) return 0.0f; \n"
                fragmentBody += "   if (t > b) return 1.0f; \n"
                fragmentBody += "   return (t - a)/(b - a); \n"
                fragmentBody += "} \n"
                fragmentBody += "vec3 brickTextureNodePluginFragment(vec3 color1, vec3 color2, float blur, vec2 uv, vec2 fs) \n"
                fragmentBody += "{ \n"
                fragmentBody += "   uv -= floor(uv); \n"
                fragmentBody += "   float v1 = 0.05f; float v2 = 0.45f; float v3 = 0.55f; float v4 = 0.95f; \n"
                fragmentBody += "   float u1 = 0.05f; float u2 = 0.45f; float u3 = 0.55f; float u4 = 0.95f; \n"
                fragmentBody += "   float du = blur*fs.x/2.0f; \n"
                fragmentBody += "   float dv = blur*fs.y/2.0f; \n"
                fragmentBody += "   float t = max( \n"
                fragmentBody += "       min(btnplinearstep(uv.y, v1 - dv, v1 + dv) - btnplinearstep(uv.y, v2 - dv, v2 + dv), \n"
                fragmentBody += "           max(btnplinearstep(uv.x, u3 - du, u3 + du), 1.0f - btnplinearstep(uv.x, u2 - du, u2 + du))), \n"
                fragmentBody += "       min(btnplinearstep(uv.y, v3 - dv, v3 + dv) - btnplinearstep(uv.y, v4 - dv, v4 + dv), \n"
                fragmentBody += "           btnplinearstep(uv.x, u1 - du, u1 + du) - btnplinearstep(uv.x, u4 - du, u4 + du))); \n"
                fragmentBody += "   return t*color1 + (1.0f - t)*color2; \n"
                fragmentBody += "} \n]]>"
                fragmentBody += "       </source>"
                fragmentBody += "   </implementation>"
                fragmentBody += "   </implementation>"
                fragmentBody += "</fragment>"

                fragmentMgr.addShadeFragmentFromBuffer(fragmentBody, False)

    def supportedDrawAPIs(self):
        return omr.MRenderer.kOpenGL | omr.MRenderer.kOpenGLCoreProfile | omr.MRenderer.kDirectX11

    def fragmentName(self):
        return "brickTextureNodePluginFragment"


##
## Plugin setup
#######################################################
sRegistrantId = "brickTexturePlugin"

def initializePlugin(obj):
    plugin = om.MFnPlugin(obj, "Autodesk", "4.5", "Any")
    try:
        userClassify = "texture/2d:drawdb/shader/texture/2d/brickTexture"
        plugin.registerNode("brickTexture", brickTextureNode.id, brickTextureNode.creator, brickTextureNode.initialize, om.MPxNode.kDependNode, userClassify)
    except:
        sys.stderr.write("Failed to register node\n")
        raise

    try:
        global sRegistrantId
        omr.MDrawRegistry.registerShadingNodeOverrideCreator("drawdb/shader/texture/2d/brickTexture", sRegistrantId, brickTextureNodeOverride.creator)
    except:
        sys.stderr.write("Failed to register override\n")
        raise

def uninitializePlugin(obj):
    plugin = om.MFnPlugin(obj)
    try:
        plugin.deregisterNode(brickTextureNode.id)
    except:
        sys.stderr.write("Failed to deregister node\n")
        raise

    try:
        global sRegistrantId
        omr.MDrawRegistry.deregisterShadingNodeOverrideCreator("drawdb/shader/texture/2d/brickTexture", sRegistrantId)
    except:
        sys.stderr.write("Failed to deregister override\n")
        raise