2016/10/09

無偏差( unbiased)算圖的真相

原文 / the truth about unbiased rendering
作者 / ChaosGroup lab
編譯 / Hammer Chen

多年來,大家都在爭執到底是偏差式算圖(biased)或是無偏差式算圖(unbiased)哪個比較好。『無偏差式的算圖』這個詞已被用了許多次了,幾乎等於精確算圖的代言人。事實上幾乎所有的算圖器其實多多少少都帶有偏差,即使是那些宣稱是無偏差的算圖器。 因為偏差式算圖真的比較快,更智慧,也不代表就不精確。為了要更了解這點,我們分成幾個方面來了解:


2016/10/04

Phoenix FD 3 vs FumeFX 4 Comparison

by Hammer Chen

last update: 2016/10/04


price
USD 845*
USD 830*
Simulation capability
fire, smoke and explosion
Fire, smoke, explosion, water, high viscosity fluid, Infinite ocean with splash and foam, beer foam, boat wake
UI
Floating UI
Rollout
cache file path
Absolute path
Relative path to scene, $(implicit)
Adaptive Grid
YES, plus expanding grid option
Fully controlled, fit in cam view
Opacity for smoke and fire
One for fire, one for smoke
shared One for fire, one for smoke
Particle shader

PHXFoam, able to render (large amount of) particle
Default Object Interaction
Inclusive list
Exclusive list
Ocean Texture Map

PhoenixFDOcean Tex
Color gradient / curve  editor
user friendly
difficult friendly with advanced controls
Particle source control
user friendly, radius with curve editor
through particle size or "Custom Prt Size"
Gravity helper
YES, straightforward and effective

Other forces

PlainForce, BodyForce and WaveForce
2D Simulation

YES
Viewport preview

accurate viewport preview
auto reduction
auto range
Interactive simulation (Simulation not locking the gui)
YES (start form FumeFX 4.0)
YES
Amp. resolution
Wavelet
Resimulation: wavelet, interpolate
retime
YES, Post Processing
YES, resimulation /time blend: general purpose or slow down
Mode: Linear, cache index, Loop
Frm.Blend: Interpolation, velocity
Workflow for resim / select cache
straightforward, Sim Mode
Automatic switch caches, might be confusing for beginner
Inertial forces
YES, Use Grid Motion
YES, can link sim grid to moving object, i.e.: moving torch
Dynamic solvers
Solvers: CG and QCG Advection: Default, Advanced (fields), Advanced(fields and vels)
Conservation: Direct Symmetric, Direct Smooth and Buffered, PCG Symmetric
Advection methods: Classic, Slow moving, Forward transfer, Multi-pass and FLIP
Advanced vorticity
vorticity II
Massive vorticity
Fluid Mapping
YES

heathaze

YES
displace voxels post-sim
NO
YES
Fire create smokes
YES
YES, Fuel: enable burning
Smoke buoyancy
Sensitive to dynamic, unlimited
range from 10 to -10
Cache optimization
Drop unused channels by post processing
1)Storage quality control (similar to jpeg compression)
2) No-Export Channels option in the Resimulation
Import Field3D, openVOD
support
support
Export PRT
support
support
Export Alembic

support
Self-illuminate acceleration
Illumination map
Grid-based
Render acceleration

probabilistic shading
Black-body shader
YES
YES, Allowed gradual transition between the default Black Body Fire model and an artistic model using the 'Physically Based' option
Sharpness control
Sharpen strength for fire and smoke
Sampler type: Box, Linear and Spherical
Content Smoothing for separate channel
Render elements
FumeFXfire, FumeFXsmoke, velocity, zdepth
YES for Maya version
Integration with Particle Flow
FumeFX Birth, Follow, Test
PhoenixFD Birth, Force, Test
Integration with thinkingParticles
FumeFX Birth, Follow, Probe

GPU Preview
Floating viewport
Through 3dsmax extended viewport or
Display on current viewport
Solid mode

YES
Network simulation
through backburner
"...it is possible to send many variations of the same simulation across the network and pick the result the user likes the most..."
Backburner or Deadline,
"... several simulations with varying parameters are simulated, each on a separate computer..."
Spline Follow
YES
YES, follow path
Render Warps
YES

Effectors
YES

Learning curve

Lots of parameters, take time to learn
New Quick Presets provides several quick settings as good starting point
Renderer compatability
mentalRay
V-Ray
Customer support

Offical forum and Facebook group
*Please check official website for their local store / sales details.

related posts: