Combining Point and Line Samples for Direct Illumination Points - - PowerPoint PPT Presentation

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Combining Point and Line Samples for Direct Illumination Points - - PowerPoint PPT Presentation

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Combining Point and Line Samples for Direct Illumination Points only Points + Lines Katherine Salesin Wojciech Jarosz Motivation Combining point and line samples for direct illumination 2 Motivation Combining point and line samples for

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SLIDE 1

Combining Point and Line Samples for Direct Illumination

Katherine Salesin Wojciech Jarosz Points only Points + Lines

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SLIDE 2

Motivation

  • 2

Combining point and line samples for direct illumination

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SLIDE 3

Motivation

  • 2

Combining point and line samples for direct illumination

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SLIDE 4

Motivation

  • 2

Combining point and line samples for direct illumination

Direct lighting:

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SLIDE 5

Motivation

  • 2

Combining point and line samples for direct illumination

Direct lighting: point sampling

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SLIDE 6

Motivation

  • 2

Combining point and line samples for direct illumination

Direct lighting: point sampling and line sampling

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SLIDE 7

Theory: Direct lighting + Monte Carlo sampling

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SLIDE 8

Theory

  • 4

Combining point and line samples for direct illumination

Direct lighting

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SLIDE 9

Theory

  • 4

Combining point and line samples for direct illumination

Direct lighting

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SLIDE 10

Theory

  • 4

Combining point and line samples for direct illumination

Direct lighting

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SLIDE 11

Theory

  • 4

Combining point and line samples for direct illumination

Direct lighting

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SLIDE 12

Theory

  • 4

Combining point and line samples for direct illumination

Direct lighting

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SLIDE 13

Theory

  • 4

Combining point and line samples for direct illumination

Direct lighting

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SLIDE 14

Theory

  • 4

Combining point and line samples for direct illumination

Direct lighting

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SLIDE 15

Theory

  • 5

Combining point and line samples for direct illumination

Direct lighting

Lo Le

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SLIDE 16

Theory

  • 5

Combining point and line samples for direct illumination

Direct lighting

Lo Le

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SLIDE 17

Theory

  • 5

Combining point and line samples for direct illumination

Direct lighting

Lo Le

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SLIDE 18

Theory

  • 5

Combining point and line samples for direct illumination

Direct lighting

Lo Le

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SLIDE 19

Theory

  • 5

Combining point and line samples for direct illumination

Direct lighting

Lo Le

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SLIDE 20

Theory

  • 6

Combining point and line samples for direct illumination

Direct lighting

u v Lo Le

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SLIDE 21

Theory

  • 6

Combining point and line samples for direct illumination

Direct lighting

u v Lo Le

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SLIDE 22

Theory

  • 6

Combining point and line samples for direct illumination

Direct lighting

u v Lo Le

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SLIDE 23

Theory

  • 7

Combining point and line samples for direct illumination

Direct lighting

u v

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SLIDE 24

Theory

  • 7

Combining point and line samples for direct illumination

Direct lighting

u v

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SLIDE 25

Theory

  • 8

Combining point and line samples for direct illumination

Monte Carlo sampling

u v

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SLIDE 26

Theory

  • 8

Combining point and line samples for direct illumination

Monte Carlo sampling

u v

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SLIDE 27

Theory

  • 8

Combining point and line samples for direct illumination

Monte Carlo sampling

u v

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SLIDE 28

Theory

  • 9

Combining point and line samples for direct illumination

Monte Carlo sampling

u v

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SLIDE 29

Theory

  • 9

Combining point and line samples for direct illumination

Monte Carlo sampling

u v

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SLIDE 30

Theory

  • 9

Combining point and line samples for direct illumination

Monte Carlo sampling

u v

✗

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SLIDE 31

Theory

  • 10

Combining point and line samples for direct illumination

Line sampling [BD16]

u v

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SLIDE 32

Theory

  • 11

Combining point and line samples for direct illumination

u v

Line sampling [BD16]

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SLIDE 33

Theory

  • 12

Combining point and line samples for direct illumination

u v

Line sampling [BD16]

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SLIDE 34

Theory

  • 13

Combining point and line samples for direct illumination

u v

Line sampling [BD16]

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SLIDE 35

Theory

  • 14

Combining point and line samples for direct illumination

Monte Carlo sampling

u v

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SLIDE 36

Theory

  • 15

Combining point and line samples for direct illumination

Monte Carlo sampling

u v

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SLIDE 37

Prior work: line sampling

  • 16

Combining point and line samples for direct illumination

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SLIDE 38

Prior work: line sampling

  • Direct illumination [BD16]
  • 16

Combining point and line samples for direct illumination

[BD16]

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SLIDE 39

Prior work: line sampling

  • Direct illumination [BD16]
  • Transient light transport [MGJ*19]
  • 16

Combining point and line samples for direct illumination

[BD16]

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SLIDE 40

Prior work: line sampling

  • Direct illumination [BD16]
  • Transient light transport [MGJ*19]
  • Transmittance [BJ17]
  • 16

Combining point and line samples for direct illumination

[BJ17] [BD16]

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SLIDE 41

Prior work: line sampling

  • Direct illumination [BD16]
  • Transient light transport [MGJ*19]
  • Transmittance [BJ17]
  • Motion blur [GDA10]
  • 16

Combining point and line samples for direct illumination

[BJ17] [BD16]

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SLIDE 42

Prior work: line sampling

  • Direct illumination [BD16]
  • Transient light transport [MGJ*19]
  • Transmittance [BJ17]
  • Motion blur [GDA10]
  • Depth of field [TPD*12]
  • 16

Combining point and line samples for direct illumination

[BJ17] [BD16]

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SLIDE 43

Prior work: line sampling

  • Direct illumination [BD16]
  • Transient light transport [MGJ*19]
  • Transmittance [BJ17]
  • Motion blur [GDA10]
  • Depth of field [TPD*12]
  • Environment lights [NBMJ14]
  • 16

Combining point and line samples for direct illumination

[BJ17] [BD16]

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SLIDE 44

Prior work: line sampling

  • Direct illumination [BD16]
  • Transient light transport [MGJ*19]
  • Transmittance [BJ17]
  • Motion blur [GDA10]
  • Depth of field [TPD*12]
  • Environment lights [NBMJ14]
  • Hair [BGA12]
  • 16

Combining point and line samples for direct illumination

[BJ17] [BD16]

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SLIDE 45

Prior work: line sampling

  • Direct illumination [BD16]
  • Transient light transport [MGJ*19]
  • Transmittance [BJ17]
  • Motion blur [GDA10]
  • Depth of field [TPD*12]
  • Environment lights [NBMJ14]
  • Hair [BGA12]
  • and more…
  • 16

Combining point and line samples for direct illumination

[BJ17] [BD16]

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SLIDE 46

Line sampling: pros and cons

  • 17

Combining point and line samples for direct illumination

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SLIDE 47

Line sampling: pros and cons

✓ Less error per sample than points

  • 17

Combining point and line samples for direct illumination

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SLIDE 48

Line sampling: pros and cons

✓ Less error per sample than points ✓ Better convergence rate than points (if stratified)

  • 17

Combining point and line samples for direct illumination

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SLIDE 49

Line sampling: pros and cons

✓ Less error per sample than points ✓ Better convergence rate than points (if stratified)

  • BUT convergence rate may depend on line orientation [SMJ17]
  • 17

Combining point and line samples for direct illumination

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SLIDE 50

Line sampling: pros and cons

✓ Less error per sample than points ✓ Better convergence rate than points (if stratified)

  • BUT convergence rate may depend on line orientation [SMJ17]

✗ Hard to analytically integrate one dimension

  • 17

Combining point and line samples for direct illumination

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SLIDE 51

Line sampling: pros and cons

✓ Less error per sample than points ✓ Better convergence rate than points (if stratified)

  • BUT convergence rate may depend on line orientation [SMJ17]

✗ Hard to analytically integrate one dimension

  • [BD16] derived solution only for diffuse and Phong materials
  • 17

Combining point and line samples for direct illumination

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SLIDE 52

Line sampling: pros and cons

✓ Less error per sample than points ✓ Better convergence rate than points (if stratified)

  • BUT convergence rate may depend on line orientation [SMJ17]

✗ Hard to analytically integrate one dimension

  • [BD16] derived solution only for diffuse and Phong materials

✗ Slow to evaluate samples

  • 17

Combining point and line samples for direct illumination

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SLIDE 53

Line sampling: pros and cons

✓ Less error per sample than points ✓ Better convergence rate than points (if stratified)

  • BUT convergence rate may depend on line orientation [SMJ17]

✗ Hard to analytically integrate one dimension

  • [BD16] derived solution only for diffuse and Phong materials

✗ Slow to evaluate samples

  • Expensive line sample-scene intersection
  • 17

Combining point and line samples for direct illumination

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SLIDE 54

MIS Points + Points

Motivation

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SLIDE 55

MIS Points + Points

Motivation

  • Make line samples play nicely with any point-based strategy
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SLIDE 56

MIS Points + Points

Motivation

  • Make line samples play nicely with any point-based strategy
  • Mitigate orientation-based performance issues
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SLIDE 57

MIS Points + Points

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SLIDE 58

(Ours) MIS Points + Lines

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SLIDE 59

Roadmap

  • 20

Combining point and line samples for direct illumination

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SLIDE 60

Roadmap

  • Reframe line samples as point samples that

importance sample visibility

  • 20

Combining point and line samples for direct illumination

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SLIDE 61

Roadmap

  • Reframe line samples as point samples that

importance sample visibility

  • Show how to multiple importance sample between

lines and points, and lines of different orientations

  • 20

Combining point and line samples for direct illumination

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SLIDE 62

Roadmap

  • Reframe line samples as point samples that

importance sample visibility

  • Show how to multiple importance sample between

lines and points, and lines of different orientations

  • Propose novel MIS weighting scheme to improve

convergence rate

  • 20

Combining point and line samples for direct illumination

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SLIDE 63

Main idea

  • 21

Combining point and line samples for direct illumination

u v

u v

Line sampling Point sampling

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SLIDE 64

Line sampling Point sampling

Main idea

  • 22

Combining point and line samples for direct illumination

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SLIDE 65

Line sampling Point sampling

Main idea

  • 22

Combining point and line samples for direct illumination

constant

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SLIDE 66

Line sampling Point sampling

Main idea

  • 22

Combining point and line samples for direct illumination

constant zero

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SLIDE 67

Main idea

  • 23

Combining point and line samples for direct illumination

Line sampling Point sampling

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SLIDE 68

Main idea

  • 23

Combining point and line samples for direct illumination

Line sampling Point sampling

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SLIDE 69

Main idea

  • 24

Combining point and line samples for direct illumination

Line sampling Point sampling

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SLIDE 70

Main idea

  • 24

Combining point and line samples for direct illumination

Line sampling Point sampling

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SLIDE 71

Main idea

  • 24

Combining point and line samples for direct illumination

Line sampling Point sampling

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SLIDE 72

Main idea

  • 25

Combining point and line samples for direct illumination

Line sampling Point sampling

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SLIDE 73

Main idea

  • 25

Combining point and line samples for direct illumination

Line sampling Point sampling

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SLIDE 74

Main idea

  • 26

Combining point and line samples for direct illumination

Line sampling Point sampling

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SLIDE 75

Main idea

  • 27

Combining point and line samples for direct illumination

Line sampling Point sampling

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SLIDE 76

Main idea

  • 27

Combining point and line samples for direct illumination

Line sampling Point sampling

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SLIDE 77

Main idea

  • 28

Combining point and line samples for direct illumination

Line sampling Point sampling

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SLIDE 78

Main idea

  • 28

Combining point and line samples for direct illumination

Line sampling Point sampling

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SLIDE 79

Main idea

  • 29

Combining point and line samples for direct illumination

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SLIDE 80
  • But a perfect conditional pdf would be hard to find for

the full direct lighting integral

Main idea

  • 29

Combining point and line samples for direct illumination

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SLIDE 81
  • But a perfect conditional pdf would be hard to find for

the full direct lighting integral

  • Instead, we use simpler conditional pdfs that work well in practice

Main idea

  • 29

Combining point and line samples for direct illumination

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SLIDE 82
  • But a perfect conditional pdf would be hard to find for

the full direct lighting integral

  • Instead, we use simpler conditional pdfs that work well in practice
  • Effectively importance sampling visibility

Main idea

  • 29

Combining point and line samples for direct illumination

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SLIDE 83

Main idea

We propose two options:

  • 30

Combining point and line samples for direct illumination

Conditional point pdfs

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SLIDE 84

Main idea

We propose two options:

  • 30

Combining point and line samples for direct illumination

Conditional point pdfs

Surface-area-based sampling (uniform over surface area)

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SLIDE 85

Main idea

We propose two options:

  • 30

Combining point and line samples for direct illumination

Conditional point pdfs

Surface-area-based sampling (uniform over surface area) Solid-angle-based sampling (uniform over solid angle) from [UFK13]

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SLIDE 86

Summary

  • 31

Combining point and line samples for direct illumination

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SLIDE 87

Summary

  • We have reframed line sampling as point sampling

that importance samples visibility

  • 31

Combining point and line samples for direct illumination

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SLIDE 88

Summary

  • We have reframed line sampling as point sampling

that importance samples visibility

  • We can now use line sampling with any BRDF
  • 31

Combining point and line samples for direct illumination

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SLIDE 89

Summary

  • We have reframed line sampling as point sampling

that importance samples visibility

  • We can now use line sampling with any BRDF
  • But line samples are still bad at importance sampling

some terms – can we do better?

  • 31

Combining point and line samples for direct illumination

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SLIDE 90

Theory

  • 32

Combining point and line samples for direct illumination

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SLIDE 91
  • We can use multiple importance sampling (MIS) to

combine the strengths of different strategies

Theory

  • 32

Combining point and line samples for direct illumination

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SLIDE 92
  • We can use multiple importance sampling (MIS) to

combine the strengths of different strategies

  • MIS uses a set of weights to favor each strategy where

it is strongest (i.e. where a strategy’s pdf is largest relative to other strategies’ pdfs)

Theory

  • 32

Combining point and line samples for direct illumination

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SLIDE 93

Summary

  • 33

Combining point and line samples for direct illumination

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SLIDE 94

Summary

  • We can now MIS lines with lines of other orientations
  • 33

Combining point and line samples for direct illumination

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SLIDE 95

MIS between lines: Equal time comparison

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SLIDE 96
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SLIDE 97
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SLIDE 98
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SLIDE 99

Relative MSE

Full image Green Purple Lines (average) [BD16] 2.6 x 10–1 1.2 x 10–2 1.5 x 100 Equal time comparison

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SLIDE 100

Relative MSE

Full image Green Purple Lines (average) [BD16] 2.6 x 10–1 1.2 x 10–2 1.5 x 100 Solid-angle points [UFK13] 2.0 x 10–1 1.4 x 10–3 1.9 x 100 Equal time comparison

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SLIDE 101

Full image Green Purple Lines (average) [BD16] 2.6 x 10–1 1.2 x 10–2 1.5 x 100 Solid-angle points [UFK13] 2.0 x 10–1 1.4 x 10–3 1.9 x 100 MIS lines [Ours] 1.0 x 10–1 2.6 x 10–3 3.3 x 10-1

Relative MSE

Equal time comparison

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SLIDE 102

Summary

  • We can now MIS lines with lines of other orientations
  • 39

Combining point and line samples for direct illumination

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SLIDE 103

Summary

  • We can now MIS lines with lines of other orientations
  • We can now MIS lines with points that importance

sample other distributions (like BRDFs)

  • 39

Combining point and line samples for direct illumination

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SLIDE 104

MIS between points and lines: Equal time comparisons

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SLIDE 105
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SLIDE 106
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SLIDE 107

Full image BSDF 5.5 x 101

Relative MSE

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SLIDE 108

Full image BSDF 5.5 x 101

Relative MSE

Equal time comparison

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SLIDE 109

Full image BSDF 5.5 x 101 Solid-angle points [UFK13] 4.5 x 10–1

Relative MSE

Equal time comparison

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SLIDE 110

Full image BSDF 5.5 x 101 Solid-angle points [UFK13] 4.5 x 10–1 MIS BSDF + SA points 2.0 x 10-1

Relative MSE

Equal time comparison

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SLIDE 111

Full image BSDF 5.5 x 101 Solid-angle points [UFK13] 4.5 x 10–1 MIS BSDF + SA points 2.0 x 10-1 Solid-angle lines [Ours]

4.2 x 10–1

Relative MSE

Equal time comparison

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SLIDE 112

Full image BSDF 5.5 x 101 Solid-angle points [UFK13] 4.5 x 10–1 MIS BSDF + SA points 2.0 x 10-1 Solid-angle lines [Ours]

4.2 x 10–1

MIS BSDF + SA lines

6.8 x 10–2

Relative MSE

Equal time comparison

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SLIDE 113
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SLIDE 114
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SLIDE 115

Full image Green Purple 4 points : 0 lines 4.0 x 10–1 5.7 x 10–2 4.4 x 10–1

Relative MSE

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SLIDE 116

Full image Green Purple 4 points : 0 lines 4.0 x 10–1 5.7 x 10–2 4.4 x 10–1

Relative MSE

Equal time comparison

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SLIDE 117

Full image Green Purple 4 points : 0 lines 4.0 x 10–1 5.7 x 10–2 4.4 x 10–1 3 points : 1 line 1.0 x 100 1.1 x 10–1 1.1 x 10–1

Relative MSE

Equal time comparison

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SLIDE 118

Full image Green Purple 4 points : 0 lines 4.0 x 10–1 5.7 x 10–2 4.4 x 10–1 3 points : 1 line 1.0 x 100 1.1 x 10–1 1.1 x 10–1 2 points : 2 lines 1.0 x 101 5.2 x 10–1 9.8 x 10–2

Relative MSE

Equal time comparison

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SLIDE 119

Full image Green Purple 4 points : 0 lines 4.0 x 10–1 5.7 x 10–2 4.4 x 10–1 3 points : 1 line 1.0 x 100 1.1 x 10–1 1.1 x 10–1 2 points : 2 lines 1.0 x 101 5.2 x 10–1 9.8 x 10–2 1 point : 3 lines

2.8 x 10–1

5.5 x 10–1 1.3 x 10–1

Relative MSE

Equal time comparison

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SLIDE 120

Full image Green Purple 4 points : 0 lines 4.0 x 10–1 5.7 x 10–2 4.4 x 10–1 3 points : 1 line 1.0 x 100 1.1 x 10–1 1.1 x 10–1 2 points : 2 lines 1.0 x 101 5.2 x 10–1 9.8 x 10–2 1 point : 3 lines

2.8 x 10–1

5.5 x 10–1 1.3 x 10–1 0 points : 4 lines

5.3 x 10–1

1.9 x 101 1.1 x 10–1

Relative MSE

Equal time comparison

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SLIDE 121

Summary

  • We can now MIS lines with lines of other orientations
  • We can now MIS lines with points that importance

sample other distributions (like BRDFs)

  • 54

Combining point and line samples for direct illumination

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SLIDE 122

Summary

  • We can now MIS lines with lines of other orientations
  • We can now MIS lines with points that importance

sample other distributions (like BRDFs)

  • But MIS inherits the worst convergence rate of its

strategies – can we do better?

  • 54

Combining point and line samples for direct illumination

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SLIDE 123

Discontinuity-smoothing MIS

  • 55

Combining point and line samples for direct illumination

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SLIDE 124
  • We know convergence rate improves when

discontinuities in effective integrand are smoothed

Discontinuity-smoothing MIS

  • 55

Combining point and line samples for direct illumination

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SLIDE 125
  • We know convergence rate improves when

discontinuities in effective integrand are smoothed

  • MIS estimator:

Discontinuity-smoothing MIS

  • 55

Combining point and line samples for direct illumination

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SLIDE 126
  • We know convergence rate improves when

discontinuities in effective integrand are smoothed

  • MIS estimator:

Discontinuity-smoothing MIS

  • 55

Combining point and line samples for direct illumination

for S strategies

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SLIDE 127
  • We know convergence rate improves when

discontinuities in effective integrand are smoothed

  • MIS estimator:

Discontinuity-smoothing MIS

  • 55

Combining point and line samples for direct illumination

for S strategies

effective integrand

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SLIDE 128
  • We know convergence rate improves when

discontinuities in effective integrand are smoothed

  • MIS estimator:

Discontinuity-smoothing MIS

  • 55

Combining point and line samples for direct illumination

for S strategies

effective integrand [SSC*19]

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SLIDE 129
  • We know convergence rate improves when

discontinuities in effective integrand are smoothed

  • MIS estimator:

Discontinuity-smoothing MIS

  • 55

Combining point and line samples for direct illumination

for S strategies

effective integrand [Ours]

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SLIDE 130

Discontinuity-smoothing MIS

  • 56

Combining point and line samples for direct illumination

Let us MIS:

  • 1. BRDF point samples
  • 2. Vertical line samples
  • 3. Horizontal line samples
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SLIDE 131

Effective integrand for the BRDF strategy without smoothing light

Discontinuity-smoothing MIS

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SLIDE 132

Effective integrand for the BRDF strategy without smoothing light

Discontinuity-smoothing MIS

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SLIDE 133

Effective integrand for the BRDF strategy without smoothing light

Discontinuity-smoothing MIS

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SLIDE 134

Effective integrand for the BRDF strategy without smoothing light

Discontinuity-smoothing MIS

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SLIDE 135

Effective integrand for the BRDF strategy without smoothing light

Discontinuity-smoothing MIS

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SLIDE 136

Effective integrand for the BRDF strategy without smoothing light

Discontinuity-smoothing MIS

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SLIDE 137

Effective integrand for the BRDF strategy without smoothing light

Discontinuity-smoothing MIS

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SLIDE 138

light

Discontinuity-smoothing MIS

Effective integrand for the BRDF strategy with smoothing

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SLIDE 139

Smoothing MIS: Convergence tests

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SLIDE 140

Convergence tests

  • 61

Combining point and line samples for direct illumination

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SLIDE 141

Convergence tests

  • 61

Combining point and line samples for direct illumination

A

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SLIDE 142

Convergence tests

  • 61

Combining point and line samples for direct illumination

Number of Light Samples V a r i a n c e

Pixel A

A

(multijittered)

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SLIDE 143

Convergence tests

  • 61

Combining point and line samples for direct illumination

Number of Light Samples V a r i a n c e

Pixel A

A

BSDF (N–1.38)

(multijittered)

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SLIDE 144

Convergence tests

  • 61

Combining point and line samples for direct illumination

Number of Light Samples V a r i a n c e

Pixel A

A

BSDF (N–1.38)

  • Horiz. lines (N–2.13)

(multijittered)

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SLIDE 145

Convergence tests

  • 61

Combining point and line samples for direct illumination

Number of Light Samples V a r i a n c e

Pixel A

A

BSDF (N–1.38)

  • Horiz. lines (N–2.13)
  • Vert. lines (N–2.14)

(multijittered)

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SLIDE 146

Convergence tests

  • 61

Combining point and line samples for direct illumination

Number of Light Samples V a r i a n c e

Pixel A

A

BSDF (N–1.38)

  • Horiz. lines (N–2.13)
  • Vert. lines (N–2.14)

MIS BSDF + Lines (N–1.40)

(multijittered)

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SLIDE 147

Convergence tests

  • 61

Combining point and line samples for direct illumination

Number of Light Samples V a r i a n c e

Pixel A

A

BSDF (N–1.38)

  • Horiz. lines (N–2.13)
  • Vert. lines (N–2.14)

MIS BSDF + Lines (N–1.40) MIS BSDF + Lines with smoothing (N–2.04)

(multijittered)

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SLIDE 148

Convergence tests

  • 62

Combining point and line samples for direct illumination

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SLIDE 149

Convergence tests

  • 62

Combining point and line samples for direct illumination

B

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SLIDE 150

Convergence tests

  • 62

Combining point and line samples for direct illumination

B

Number of Light Samples V a r i a n c e

Pixel B

(multijittered)

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SLIDE 151

Convergence tests

  • 62

Combining point and line samples for direct illumination

B

BSDF (N–1.48)

Number of Light Samples V a r i a n c e

Pixel B

(multijittered)

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SLIDE 152

Convergence tests

  • 62

Combining point and line samples for direct illumination

B

BSDF (N–1.48)

  • Horiz. lines (N–2.57)

Number of Light Samples V a r i a n c e

Pixel B

(multijittered)

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SLIDE 153

Convergence tests

  • 62

Combining point and line samples for direct illumination

B

BSDF (N–1.48)

  • Horiz. lines (N–2.57)
  • Vert. lines (N–1.61)

Number of Light Samples V a r i a n c e

Pixel B

(multijittered)

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SLIDE 154

Convergence tests

  • 62

Combining point and line samples for direct illumination

B

BSDF (N–1.48)

  • Horiz. lines (N–2.57)
  • Vert. lines (N–1.61)

MIS BSDF + Lines (N–1.53)

Number of Light Samples V a r i a n c e

Pixel B

(multijittered)

slide-155
SLIDE 155

Convergence tests

  • 62

Combining point and line samples for direct illumination

B

BSDF (N–1.48)

  • Horiz. lines (N–2.57)
  • Vert. lines (N–1.61)

MIS BSDF + Lines (N–1.53) MIS BSDF + Lines with smoothing (N–1.68)

Number of Light Samples V a r i a n c e

Pixel B

(multijittered)

slide-156
SLIDE 156

Wrapping things up:
 What’s Next?

slide-157
SLIDE 157

Future work

  • 64

Combining point and line samples for direct illumination

slide-158
SLIDE 158

Future work

  • Optimize the line sample-scene intersection
  • 64

Combining point and line samples for direct illumination

slide-159
SLIDE 159

Future work

  • Optimize the line sample-scene intersection
  • Line sample-scene intersection 1.2x – 55x slower than shadow ray
  • 64

Combining point and line samples for direct illumination

slide-160
SLIDE 160

Future work

  • Optimize the line sample-scene intersection
  • Line sample-scene intersection 1.2x – 55x slower than shadow ray
  • Support arbitrarily-shaped light sources and all line

directions (for solid-angle lines)

  • 64

Combining point and line samples for direct illumination

slide-161
SLIDE 161

Future work

  • Optimize the line sample-scene intersection
  • Line sample-scene intersection 1.2x – 55x slower than shadow ray
  • Support arbitrarily-shaped light sources and all line

directions (for solid-angle lines)

  • Improve smoothing MIS heuristic to be more robust to

all scenarios

  • 64

Combining point and line samples for direct illumination

slide-162
SLIDE 162

Future work

  • Optimize the line sample-scene intersection
  • Line sample-scene intersection 1.2x – 55x slower than shadow ray
  • Support arbitrarily-shaped light sources and all line

directions (for solid-angle lines)

  • Improve smoothing MIS heuristic to be more robust to

all scenarios

  • Apply novel concepts to other line sampling (or even

higher-dimensional) applications

  • 64

Combining point and line samples for direct illumination

slide-163
SLIDE 163

Thank you!

Please visit dartgo.org/pointsandlines for the full paper, supplemental document, and interactive image viewer.

katherine.a.salesin.gr@dartmouth.edu wojciech.k.jarosz@dartmouth.edu

Katherine Salesin Wojciech Jarosz

Scan Me!

slide-164
SLIDE 164

Thank you!

Please visit dartgo.org/pointsandlines for the full paper, supplemental document, and interactive image viewer.

katherine.a.salesin.gr@dartmouth.edu wojciech.k.jarosz@dartmouth.edu

Katherine Salesin Wojciech Jarosz

Scan Me!