https://github.com/miloyip/light2d

Light rendering in 2D
https://github.com/miloyip/light2d

constructive-solid-geometries global-illumination graphics-programming graphics2d monte-carlo-integration signed-distance-field

Last synced: 10 months ago
JSON representation

Light rendering in 2D

• Host: GitHub
• URL: https://github.com/miloyip/light2d
• Owner: miloyip
• Created: 2017-11-04T19:27:15.000Z (over 8 years ago)
• Default Branch: master
• Last Pushed: 2022-01-08T10:51:29.000Z (about 4 years ago)
• Last Synced: 2025-03-28T11:09:04.596Z (11 months ago)
• Topics: constructive-solid-geometries, global-illumination, graphics-programming, graphics2d, monte-carlo-integration, signed-distance-field
• Language: C
• Size: 10.5 MB
• Stars: 863
• Watchers: 61
• Forks: 125
• Open Issues: 4
• Metadata Files:
  • Readme: README.md

Awesome Lists containing this project

README

          
# light2d

This project illustrates light rendering in 2D with C.

All samples output PNGs with [svpng](https://github.com/miloyip/svpng).

License: public domain.

# Basic

Use Monte Carol integration and ray marching of signed distance field (SDF) to render a emissive circle.

Source code: [basic.c](basic.c)

Uniform sampling (64 samples per pixel):

![ ](basic_a64.png)

Uniform sampling with different number of samples per pixel:

![ ](basic_varyingn.png)

Stratified sampling (64 samples per pixel):

![ ](basic_b64.png)

Jittered sampling (64 samples per pixel):

![ ](basic_c64.png)

Various sampling method side-by-side comparison (64 samples per pixel)::

![ ](basic_varyingsampling.png)

# Constructive Solid Geometry

Source code: [csg.c](csg.c)

Use union operation for creating multiple shapes:

![ ](csg_scene.png)

Various CSG operations on two circles:

![ ](csg_ops.png)

# Shapes

Source code: [shapes.c](shapes.c)

Examples of various shapes defined by SDF:

![ ](shapes.png)

![ ](m.png)

# Reflection

Source code: [reflection.c](reflection.c)

![ ](vector_reflect.png)

Test scene with two boxes:

![ ](reflection_boxscene.png)

Visualization of SDF gradient, which is approximated by central difference:

![ ](reflection_boxgradient.png)

Reflection via recursive tracing:

![ ](reflection_box.png)

Concave mirror scene generates caustics effect:

![ ](reflection_concavemirror.png)

# Refraction

Source code: [refraction.c](refraction.c)

Applying Snell's law to compute refraction direction. Total internal reflection is also handled.

![ ](vector_refract.png)

Test scenes:

![ ](refraction_box.png)

![ ](refraction_concavelens.png)

![ ](refraction_convexlens.png)

![ ](refraction_semicircular.png)

![ ](m2.png)

# Fresnel Reflectance

Source code: [fresnel.c](fresnel.c)

Applying Fresnel equation to compute reflectance of dielectric medium.

![ ](vector_fresnel.png)

Without Fresnel:

![ ](refraction_montage.png)

With Fresnel term:

![ ](fresnel_montage.png)

# Beer-Lambert

Source code: [beerlambert.c](beerlambert.c) [beerlambert_color.c](beerlambert_color.c)

Applying Beer-Lambert law to simulate absorption of light in medimum.

![ ](beerlambert_montage.png)

![ ](beerlambert_color.png)

![ ](heart.png)