direct volume rendering w/shading via three- dimensional textures
Post on 22-Dec-2015
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Direct Volume Rendering w/Shading via Three-Dimensional Textures
Introduction
Intro Limitations Other methods
Overview of Texture-Map
Initial step Lookup table computation Texture map processing
Ambient Light
Calculation
Reflecting Surface Classification Calculation
Reflected Light Component
Half-way vector specularity model Lambertian diffuse shading
Gradient Quantization
Quantize gradient direction Unit Sphere Tessellation
Rendering Slices
Apply texture Back to front ordering
Texture Coords
Bounding cube Transformation:
Alternative Pipelines
Results
Footprint Evaluation for Volume Rendering
Introduction
Forward-Mapping Algorithm Overview
Previous Work
Ray tracing Compositing techniques Fitting surfaces into data cells
Rendering Algorithm
Differences from original algorithm Algorithm breakdown
Transforming Shading Reconstruction Visibility
Splatting
Footprint Function
Calculate once for each view
Generic Footprint Table
Spherical Kernel Integration along the Z
axis
Extents and Mapping
Two cases
Extents and Mapping (cont.)
Extent
Mapping
Ellipsoid defined as
Table Sizes and Kernels
3 Parameters Size of the table
Space vs. Quality tradeoff
Accessibility of the table
Table’s underlying kernel
Table Sizes and Kernels (cont.)
Sample Images
Sample Images (cont.)