v4.0.0-alpha.1 (2023-08-11)

[hollasch]

It's been quite a while since our last release of v3.2.3 at the end of 2020. For this cycle, we've tackled a load of significant backlog items, including rewrites of much of our underlying code. As always, the primary idea isn't to provide the best or most optimal implemntation, but instead to put out simple, sometimes crude first approximations of the main components of writing a ray tracer.

Highlights include large rewrites and expansions of the book text, a large refactoring of our camera class, folding moving_sphere functionality into sphere, adding a new interval class for use in multiple contexts, creating a new general quad primitive to replace the old *_rect primitives, and the addressing of hundreds of issues and requested features. The line-item changes below should give you an idea of v4 includes.

In order to drive this release to resolution, we're releasing our alpha.1 version to coincide with the start of SIGGRAPH 2023. We've pretty much finished with book one, though there's a fair amount left for books two and three. Our plan is to keep crunching for a final v4.0.0 release by the end of 2023.

Since this is an alpha, we would greatly appreciate any feedback you might have. Let us know by creating issues up on the GitHub project.

Common

• Fix - CSS fix for cases where code listing overflows; change to fit content (Code appears to come out of the box #826)
• Fix - Enabled compiler warnings for MSVC, Clang, GNU. Cleaned up warnings as fit (Lint pass: ctor initializer order + virtual dtors #865)
• Fix - Remove redundant virtual keyword for methods with override (Delete virtual keyword for overriding methods #805)
• Fix - rect hit returning NaNs and infinities (Bug: rect hit returning NaN's, Infinities #681)
• Fix - Add \mathit to italic math variables to fix slight kerning issues in equations (Math cleanup pass #839)
• Fix - Fixed issues in Bib(La)TeX entries.
• Change - Use class instead of struct throughout for simpler C++ (Use class instead of struct everywhere #781)
• Change - Moved all class method definitions inside class definition (Move method definitions inside classes #802)
• Change - Class public/private access labels get consistent two-space indents (Class public/private labels get two-space indents #782)
• Change - Updated classes to use private access for class-private variables (Revisit public vs private member variable access qualifiers #869)
• Change - Made our code inline clean. We now use inline in all header function definitions to
  guard against copies in multiple C++ translation units (Eliminate inline keywords #803)
• Change - Retired the src/common/ directory. Each book now has complete source in one directory
• Change - Significant rewrite and expansion of the camera class
• Change - aabb class constructor treats two params as extreme points in any orientation (bvh_node is broken with negative-radius spheres #733)
• Change - hittable:hit() methods use new interval class for ray-t parameter
• Change - interval::clamp() replaces standalone clamp utility function
• Change - aabb class uses intervals for each axis (Refactor AABB class to use interval class #796)
• Change - hittable member variable ptr renamed to object
• Change - general rename of mat_ptr to mat (material)
• Change - hittable::bounding_box() signature has changed to always return a value (Change hittable::bounding_box method signature #859)
• Change - replaced random vector in isotropic with random_unit_vector
• Change - Use std::clog instead of std::cerr to log scanline progress (Use of std::flush in std::cerr #935)
• Change - Updated figures throughout for improved clarity when possible
• Change - Generated images are now output gamma-corrected rather than in linear space
  (Polish Gamma function text and source #980, Bug? Colors are specified in linear color space #1033)
• Change - The camera class now handles images with width or height of one (Camera UV coordinates — handle images with width or height of one #682, Handle images with single pixel rows and/or columns #1040)
• New - Introduce new interval class used throughout codebase (Implement an interval class #777)
• New - rtw_image class for easier image data loading, better texture file search (Improve texture file locating #807)
• New - 2D quad primitive of arbitrary orientation (Investigate general quadrilateral object to replace existing axis-aligned rectangles (aarect.h) #756)
• New - box() utility function returns hittable_list of new quad primitives (Replace box class with a function that creates and returns a hittable_list of sides #780)
• Delete - box, xy_rect, yz_rect, xz_rect classes. These are replaced with new quad
  primitive (Refactor aarect.h #292, Replace box class with a function that creates and returns a hittable_list of sides #780, Bug: rect hit returning NaN's, Infinities #681)

In One Weekend

• Change - Updated all rendered images in text
• Change - Significant update to the diffuse reflection section (Book1 Diffuse text is confusing #696, Rewrite book 1 diffuse in more straightforward way #992)
• Change - Updated and clarified text around ray generation and the camera model
• New - More commentary about the choice between double and float (Book 1: Double vs Float more explanation #752)
• New - Software context around the shadow acne listing

The Next Week

• Fix - Fixed bvh_node constructor definition signature (Signature mismatch: bvh_node constructor #872)
• Fix - Fixed scaling for final Perlin noise texture (Book 2 > Perlin Noise > Adjusting the phase: wrong scaling #896).
• Change - Rearranged the texture-mapping presentation. The three types (solid, spatial, image)
  are now sequenced in that order, and the checker texture presented more explicitly as
  an illustration of a spatial texture.
• Change - Broad rewrite of time management for moving objects, primarily camera and
  sphere, but also impacting the API for hittable::bounding_box() (Time is broken #799)
• Change - The sphere class now includes animation capability originally in moving_sphere
  (The moving_sphere class is mostly redundant with sphere, and lacks UV coordinates #1125)
• New - Add listing to use new bvh_node class in the random_spheres scene (Book 2: Add an example for Chapter 3 #715).
• Delete - The moving_sphere class is deprecated, and functionality moved to sphere (The moving_sphere class is mostly redundant with sphere, and lacks UV coordinates #1125)

The Rest of Your Life

• Fix - Added missing functionality for isotropic (Book 3: Isotropic: missing method updates #664)
• Fix - Variable direction was used without being defined in listing 11 (Book 3 Ray Tracing For The Rest of Your Life-Listing 11 #831)
• Fix - Fixed uniform sampling (Fix uniform sampling #934)

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This discussion was created from the release v4.0.0-alpha.1 (2023-08-11).

[scott223]

Hi

first of all many thanks for this amazing material, I am learning a lot. For me however, the link https://raytracing.GitHub.io/books/RayTracingInOneWeekend.HTML does no longer work. This is the first hit on Google if I search for this book. The link worked prior to this new release

thanks
Scott

[hollasch]

This was due to a configuration issue on our end, not with this particular release. It has been fixed.