Phong shading for a 3D body
Create phong shading for faces showing on the 3D block
phong3D(aglyph, M = diag(1, nrow = 4), M2 = diag(1, nrow = 4),
Light = c(45, 45), anorms = list(), zee = c(0, 0, 1),
col = "white", border = "black")aglyph |
3-D body list of faces and normals |
M |
Rotation Matrix |
M2 |
Viewing Matrix |
Light |
light source direction |
anorms |
normals to faces |
zee |
Up vector for Body |
col |
color for faces |
border |
border color for sides |
Uses a standard phong shading model based ont eh dot product of the face normal vector and direction of incoming light.
Graphical Side effect
Jonathan M. Lees<jonathan.lees@unc.edu>
Watt, Alan. Fundamentals of Three-dimensional Computer Graphics, Addison-Wesley, 1989, 430p.
makeblock3D, BOXarrows3D, PROJ3D, Z3Darrow, pglyph3D
########### create a block and rotation matrix, then color it
ANG=(45)
DEGRAD = pi/180
y1 = 1.5
y2 = y1 - 1/tan((ANG)*DEGRAD)
z1 = 1
x1 = 1
Ablock1 = matrix(c(0,0,0,
1,0,0,
1,y1,0,
0,y1,0,
0,0,-1,
1,0,-1,
1,y2,-1,
0,y2,-1), byrow=TRUE, ncol=3)
Nblock1 = makeblock3D(Ablock1)
Light=c(45,45)
angz = -45
angx = -45
R1 = ROTZ(angz)
R2 = ROTX(angx)
M = R1
Z2 = PROJ3D(Nblock1$aglyph, M=M, anorms=Nblock1$anorm , zee=c(0,0,1))
RangesX = range(attr(Z2, "RangesX"))
RangesY = range(attr(Z2, "RangesY"))
plot( RangesX, RangesY, type='n', asp=1, ann=FALSE, axes=FALSE)
phong3D(Nblock1$aglyph, M=M, anorms=Nblock1$anorm , Light = Light,
zee=c(0,0,1), col=rgb(.7,.5, .5) , border="black")Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.