程序代写代做代考 Hive rasterize & interp figures

rasterize & interp figures

go-vxlab.csc.ncsu.edu / projectiondiscussion

http://go-vxlab.csc.ncsu.edu/projectiondiscussion

rasterization & interpolation
CGClass @ NCSU

Intro CG @ NCSU
Ben Watson

cgclass.csc.ncsu.edu

http://cgclass.csc.ncsu.edu/

rasterization

go-vxlab.csc.ncsu.edu/
rasterizeslides

http://go-vxlab.csc.ncsu.edu/rasterizeslides
http://go-vxlab.csc.ncsu.edu/rasterizeslides

history

https://archive.org/details/principlesofinter00newm

rasterize vs. ray tracing

ray tracing

ray tracing

for each pixel
for each primitive

/* shade etc */

ray tracing
(image order)

for each primitive
for each pixel

/* shade etc */

rasterization
(object order)

rasterization

rasterization

bilerp of triangles (bilerp of rectangles)

(0,1,1) = LL

(3,4,3) = U (= UL/UR)

LR = (6,2,2)

(4,3,?) = P

https://docs.google.com/presentation/d/1JiHs1Wq2Xbz7qGIcC82pPqUvpResezgP8USshq010rg/edit#slide=id.g904a4c32c9_5_226

bilerp of triangles

(0,1,1) = LL

(3,4,3) = U (= UL/UR)

LR = (6,2,2)

PL PR

(4,3,?) = P

sL = (Py-Uy) / (LLy-Uy)
sL = (3-4) / (1-4)
sL = 1 / 3

sR = (Py-Uy) / (LRy-Uy)
sR = (3-4) / (2-4)

sR = 1 / 2

(bilerp of rectangles)

https://docs.google.com/presentation/d/1JiHs1Wq2Xbz7qGIcC82pPqUvpResezgP8USshq010rg/edit#slide=id.g904a4c32c9_5_226

bilerp of triangles

(0,1,1) = LL

(3,4,3) = U (= UL/UR)

LR = (6,2,2)

PL PR

PLx = Ux + sL (LLx – Ux)
PLx = 3 + ⅓ (0 – 3) = 2

PLz = Uz + sL (LLz – Uz)
PLz = 3 + ⅓ (1 – 3) = 2⅓

PRx = Ux + sR (LRx – Ux)
PRx = 3 + ½ (6 – 3) = 4½

PRz = Uz + sR (LRz – Uz)
PRz = 3 + ½ (2 – 3) = 2½

(bilerp of rectangles)

https://docs.google.com/presentation/d/1JiHs1Wq2Xbz7qGIcC82pPqUvpResezgP8USshq010rg/edit#slide=id.g904a4c32c9_5_226

bilerp of triangles

PL PR

t = (Px – PLx) / (PRx – PLx)
t = (4 – 2) / (4½ – 2)
t = 2 / 2½ = 4 / 5

Pz = PLz + t (PRz – PLz)
Pz = 2⅓ + ⅘ (2½ – 2⅓)
Pz = 2⅓ + ⅘ ⅙ = 2 7/15

(4,3,?) = P

(bilerp of rectangles)

https://docs.google.com/presentation/d/1JiHs1Wq2Xbz7qGIcC82pPqUvpResezgP8USshq010rg/edit#slide=id.g904a4c32c9_5_226

rasterization ray tracing

rasterization ray tracing

speed faster

shadows easier

reflections easier

refractions easier

Z Z

depth complexity 2 depth complexity 5

1965 1985 2005 2015 2035

1965 1985 2005 2015 2035

rasterization

ray tracing

perspective bilerp

affine 2d bilerp perspective bilerp

Let’s say that we want to interpolate texture coordinates s
and t and have homogeneous coordinate w (with depth):

1. Perform perspective divide to go to 3d:
(s/w,t/w)

2. Append the denominator:
(s/w,t/w,1/w)

3. Perform bilerp to point p, including denominator:
(s/wp,t/wp,1/wp)

4. Undo the divide:
(sp,tp) = (s/wp / 1/wp , t/wp / 1/wp)

go deeper with readings…

https://sites.google.com/view/cgwiki-ncsu/topics/rasterization

post reactions and… we might discuss them next time
log them and… get reading credit

https://sites.google.com/view/cgwiki-ncsu/topics/rasterization
http://go-vxlab.csc.ncsu.edu/cgclassforumreadings
http://go-vxlab.csc.ncsu.edu/cgclassreadinglog

…and with videos

http://cgclass.csc.ncsu.edu/p/topic-notes.html#rasterization
(youtube)

http://cgclass.csc.ncsu.edu/p/topic-notes.html#rasterization

Requests, questions, thoughts?

go-vxlab.csc.ncsu.edu / rasterizationdiscussion

post them and… we’ll discuss them next time
log them and… get participation credit

http://go-vxlab.csc.ncsu.edu/rasterizationdiscussion

32

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TIME


ask your
questions

listen to
tunes


https://youtu.be/1cmq0c9PjRI

https://goo.gl/forms/u2Cxevg9NieeJpKy2