Rendering学習日記

ドーナツ作り。以前の記事を書き換えたものです。ありがとうございます。

#proc_torus2_pr.py

#set PYTHONPATH=C:\Python25;C:\Python\Scripts;%RMANTREE%\bin

import getpass

import time

# import the python renderman library

import prman



ri = prman.Ri() # create an instance of the RenderMan interface

ri.Option("rib", {"string asciistyle": "indented"})



filename = "proc_geom.rib"



ri.Begin(ri.RENDER)



def TorusWave(ri,nwaves,thetamax) :

	if(nwaves < 1) :

		print "need positive number of waves"

		return

	innerrad = 2.0/(8.0 * nwaves +2)

	ri.Rotate(90.0,1.0,0.0,0.0)

	ri.Sphere(innerrad,-innerrad,0,thetamax)

	outerrad =0.0

	for wave in range(1,nwaves) :

		outerrad=outerrad+(innerrad*2)

		ri.Torus(outerrad,innerrad,0.0,180.0,thetamax)

		outerrad=outerrad+(innerrad*2)

		ri.Torus(outerrad,innerrad,180.0,360.0,thetamax)

		



#ArchiveRecord is used to add elements to the rib stream in this case comments

# note the function is overloaded so we can concatinate output

ri.ArchiveRecord(ri.COMMENT, 'File ' +filename)

ri.ArchiveRecord(ri.COMMENT, "Created by " + getpass.getuser())

ri.ArchiveRecord(ri.COMMENT, "Creation Date: " +time.ctime(time.time()))



# now we add the display element using the usual elements

# FILENAME DISPLAY Type Output format

ri.Display("proc_torus2.png", "file", "rgb")

ri.Format(512, 384, -1.0)

ri.Projection(ri.PERSPECTIVE,{ri.FOV:30}) 



# now we start our world

colours ={

	"red":[1,0,0],

	"white":[1,1,1],

	"green":[0,1,0],

	"blue":[0,0,1],

	"black":[0,0,0],

	"yellow":[1,1,0]

	}



# start our world

ri.WorldBegin()

ri.LightSource("distantlight", {ri.HANDLEID: "1","to":[0,0,1]})

ri.LightSource("ambientlight", {ri.HANDLEID: "2", "intensity":[0.4]})



ri.Translate(0,0,9) #move the global view position

ri.Surface("plastic")



ri.TransformBegin()

ri.Rotate(40,1,0,0)

ri.Color(colours["red"])

ri.Attribute ("identifier",{"name": "Wave1"})

TorusWave(ri,8,360.0)

ri.TransformEnd()



ri.TransformBegin()

ri.Rotate(55,1,0,0)

ri.Color(colours["green"]) 

ri.Translate(2.2,0,0)

ri.Attribute( "identifier",{ "name" :"Wave2"})

TorusWave(ri,8,360.0)

ri.TransformEnd()



ri.TransformBegin()

ri.Rotate(35,1,0,0)

ri.Color(colours["blue"])

ri.Translate(-2.2,0,0)

ri.Attribute("identifier",{ "name" : "Wave3"})

TorusWave(ri,8,360.0)

ri.TransformEnd()

#end our world



ri.WorldEnd()

ri.End()

レイトレーシングを使わないで、それらしく見せる反射トリックですね。
レンダリングは速いです。
過去のPixarのC言語によるシーン記述をPythonで書き換えてみました。
まだまだ課題がありますが、チャレンジですね。ありがとうございます。

#generate_scn_pr.py

#Modified from a C program that generates a scene, May,1990, Pixar

#set PYTHONPATH=C:\Python25;C:\Python\Scripts;%RMANTREE%\bin

# import the python renderman library

import prman



ri = prman.Ri() # create an instance of the RenderMan interface

ri.Option("rib", {"string asciistyle": "indented"})



filename = "generate_scn.rib"



"""

 * Set RenderMan options for medium quality/speed tradeoff.

"""



REFLECTION=0





def SetupOptions():

    global REFLECTION

    ASPECT_RATIO=1.33333

    TEXTURE_ROWS=256

    IMAGE_ROWS=300

    gsz = 32

    bktsz = [12, 12]

    splits = 5

    

    #ri.Option("limits", {"gridsize": gsz,"eyesplits",:splits,"bucketsize": bktsz})

    ri.ShadingRate(2.)

    ri.PixelSamples(2., 2.)

    ri.PixelFilter(ri.BoxFilter, 1., 1.)

    

    if REFLECTION:

        ri.Display("refl.tif","file", "rgb")

        ri.Format(TEXTURE_ROWS, TEXTURE_ROWS, ASPECT_RATIO);

    else:

        ri.Display("generate_scn.tif","file", "rgb")

        ri.Format(512, 384, -1.0)

    



"""

/*

 * Set RenderMan camera parameters.

 */

"""



def SetupCamera():

    global REFLECTION

    m = [

    .970143, -0.004705, -.24249, 0,

    0, .999812, -0.0193992, 0,

    .242536, 0.01882, .96996, 0,

    -7.27607, -1.96434, 53.406, 1

    ]

    

    fov = 25.0

    

    ri.Projection(ri.PERSPECTIVE,{ri.FOV:fov}) 

    ri.Transform(m)

    

    if REFLECTION:

        #/* Transform z=0 plane to coincide with reflection plane. */

        ri.Translate(0., 0., -0.05)

        

        #/* Reflect camera through the reflection plane z=0. */

        ri.Scale(1., 1., -1.)

        #/* Transform reflection plane back to z=0. */

        ri.Translate(0., 0., 0.05);





"""

 * The model consists of three "walls" of a room (actually two

 * walls and the floor) with a mirror on one of the walls.

 * When rendering the REFLECTION image, the mirror

 * and the wall it is hanging on are both removed so that

 * the camera can see into the room from the other side of

 * the wall.

"""



def SetupModel():

    global REFLECTION

    c = [[ 0.5, 0.4, 0.1], [ 0.3, 0.5, 0.5],[ 1, 1, 1], [ 0.4, 0.2, 0.7]]

    

    if REFLECTION:

        NWALLS=2  #/* Just do two walls. */

        walls = [ [0, 0, -100,  0, 0, 0, 100, 0, -100, 100, 0, 0],[0, 100, -100, 0, 100, 0,  0, 0, -100, 0, 0, 0]]

    else:

        #ri.MakeTexture( "refl.tif", "refl.tex", "periodic", "periodic", "gaussian", 1, 1)

        NWALLS=3     #/* Do three walls and mirror. */

        walls = [ [0, 0, -100,  0, 0, 0,  100, 0, -100, 100, 0, 0],[ 0, 100, -100, 0, 100, 0,  0, 0, -100,  0, 0, 0],[ 0, 100, 0, 100, 100, 0, 0, 0, 0 , 100, 0, 0]]

        mirror = [ 5, 10.5, -.05,  10, 10.5, -.05,5, 0.5, -.05, 10, 0.5, -.05]

        

        ri.AttributeBegin()

        ri.Color(c[2])

        ri.Surface("texmap",{'string texname':"refl.tex"})

        #ri.Surface("shinymetal",{'string texturename':"refl.tex"})

        ri.Patch("bilinear",{'P': mirror})

        ri.AttributeEnd()

        

    

    ri.Color(c[0])

    for i in range(NWALLS):

        ri.Patch("bilinear",{'P': walls[i]})

        ri.Color(c[1])

        

    #/* Put a teapot in the room. */

    ri.Color(c[3])

    ri.TransformBegin()

    ri.Translate(5., 1., -2.)

    ri.Rotate(90., 0., 1., 0.)

    ri.Rotate(-90., 1., 0., 0.)

    ri.Geometry("teapot")

    ri.TransformEnd()

    



ri.Begin(ri.RENDER)



SetupCamera()



SetupOptions()



# start our world

ri.WorldBegin()

ri.LightSource("distantlight", {ri.HANDLEID: "1","to":[0,0,1]})

ri.LightSource("ambientlight", {ri.HANDLEID: "2", "intensity":[0.4]})



SetupModel()



ri.WorldEnd()

ri.End()

テクスチャについては、
MakeTexture "refl.tif" "refl.tex" "periodic" "periodic" "gaussian" 1 1
を記述したRIBを使ってtexファイルを出力しました。
Wrong state to call RiMakeTexture.なので、調べます。ありがとうございます。