rmath3d

rmath3d : Ruby Math Module for 3D Applications

rmath3d is a math module for 3D game programming and computer graphics.

• Last Update: Jul 23, 2020

• Since: Jul 20, 2008

• rmath3d (C Extension Library Implementation)

• rmath3d_plain (Pure Ruby Implementation)

Features

Supports frequently-used vector and matrix classes

• RMtx2 (2x2 matrix)
• RMtx3 (3x3 matrix)
• RMtx4 (4x4 matrix)
• RQuat (Quaternion)
• RVec2 (2-element vector)
• RVec3 (3-element vector)
• RVec4 (4-element vector)

Two implementations that are interchangeable with each other

1. rmath3d.{so|bundle} : Ruby extension library for faster execution.
2. rmath3d_plain.rb : Ruby implemantation for debugging use.

Tested Environment

Notice: This library provides native extension. You must setup develop environment (or DevKit) before installation.

• Ruby
  • ruby 2.7.1p83 (2020-03-31 revision a0c7c23c9c) [x64-mingw32]
  • Ruby 2.3 and prior versions are no longer supported.

Building rmath3d.{so|bundle}

Via RubyGems ( https://rubygems.org/gems/rmath3d ):

$ gem install rmath3d

for pure ruby version:

$ gem install rmath3d_plain

From source package

$ rake install

For mkmf users

$ ruby extconf.rb
$ make

For Windows users, type commands below via the "Visual Studio 200{5|8} Command Prompt". This process requires "cl.exe", "link.exe and "mt.exe" to be exist in the program PATH:

X:\> ruby extconf.rb
X:\> nmake

You might encounter the "MSC version unmatch: _MSC_VER: XXXX is expected." error at the time compiling "rmath3d.c". See the instruction in the extconf.rb to avoid this error.

Embedding manifest file (For Windows users)

Make sure that your rmath3d.so has "rmath3d.so.manifest" embedded into itself. Otherwise, while using rmath3d.so in your application, you might come across an error dialog saying:

---------------------------
Microsoft Visual C++ Runtime Library
---------------------------
Runtime Error!

Program: d:\ruby\bin\ruby.exe

R6034
An application has made an attempt to load the C runtime library incorrectly.
Please contact the application's support team for more information.

---------------------------
OK   
---------------------------

To ensure the file status, try checking if the string "manifest" can be found in the file:

X:\> strings rmath3d.so | grep manifest

If you don't see any outputs, it's time to embed "rmath3d.so.manifest".

X:\> mt -manifest rmath3d.so.manifest -outputresource:rmath3d.so;2

or run the "embed_manifest.bat" instead. Then check again the status.

X:\> strings rmath3d.so | grep manifest
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">

X:\> 

If you see some similar output like that, the manifest file "rmath3d.so.manifest" is successfully embedded.

About rmath3d_plain.rb

rmath3d_plain.rb is a pure Ruby version of rmath3d.so: all the functionality of rmath3d.so is implemented with plain Ruby code. It is possible to trace the bugs caused by rmath3d.so by replacing the code

gem 'rmath3d'
require 'rmath3d/rmath3d'

with

gem 'rmath3d'
require 'rmath3d/rmath3d_plain'

rmath3d_plain.rb performs more strict type checking, that might be some burden for its execution speed. So don't expect the performance efficiency when you use rmath3d_plain.rb instead of rmath3d.so.

Notes

Collaboration with ruby-opengl

The instances of RMtx4 can be used directly as the arguments of the ruby-opengl functions that accept matrices.

For example, this code snippet using RMath:

eye = RVec3.new(0.0, 15.0, 15.0)
at  = RVec3.new(0.0,  0.0,  0.0)
up  = RVec3.new(0.0,  1.0,  0.0)
mtxLookAt = RMtx4.new.lookAtRH( eye, at, up )
glMatrixMode( GL_PROJECTION )
glLoadMatrix( @mtxProj )

mtxProj = RMtx4.new.perspectiveFovRH( 30.0*Math::PI/180.0, WINDOW_WIDTH/WINDOW_HEIGHT, 0.1, 1000.0 )
glMatrixMode( GL_MODELVIEW )
glLoadMatrix( @mtxLookAt )

has the same transformation effect with the OpenGL fixed pipeline:

glMatrixMode( GL_PROJECTION )
gluPerspective( 30.0*Math::PI/180.0, WINDOW_WIDTH/WINDOW_HEIGHT, 0.1, 1000.0 )

glMatrixMode( GL_MODELVIEW )
gluLookAt( 0.0,15.0,15.0, 0.0,0.0,0.0, 0.0,1.0,0.0 )

Compatibility with matrix.rb

Currently, there is no combenient way to convert between matrix.rb's +Matrix+ and +RMtx{3|4}".

(The matrix.rb is a standard Ruby library that provides N-dimensional +Vector+ class and "N x M" +Matrix+ class.)

Information

• RubyGems
  • https://rubygems.org/gems/rmath3d
• Github

  • https://github.com/vaiorabbit/rmath3d

License

All source codes are available under the terms of the zlib/libpng license (see LICENSE.txt).