pyglpainter 2.0.1

Description:

pyglpainter 2.0.1

pyglpainter
Minimalistic, modern OpenGL drawing library for technical applications, teaching or
experimentation. It is implemented in Python 3 with Qt 6 bindings (it inherits from QOpenGLWidget).
It provides a simple Python API to draw raw OpenGL primitives (LINES, LINE_STRIP, TRIANGLES, etc.)
as well as a number of useful composite primitives
(see classes Grid, Star, CoordSystem, Text, Circle, Arc, HeightMap, OrthoLineGrid).
All objects/items can either be drawn as real
3D world entities (which optionally support "billboard" mode), or as a 2D overlay.
The user can interactively navigate using the mouse via the classical Pan-Zoom-Rotate paradigm
implemented via a virtual trackball (using quaternions for rotations).
Background
This code was originally written for a CNC application, but then split off
and made more general.
This library was developed to produce simple technical visualizations
and minimalistic line drawings in 3D space; it does not implement a hierarchical scene graph.
To be extensible, shader code has to be supplied by the application.
It uses the "modern", shader-based, OpenGL API rather than the deprecated "fixed pipeline".
Qt has been chosen not only because it provides the GL environment, but also vector, matrix and
quaternion math. A port of this Python code into native Qt C++ would therefore be trivial.
Installation
pip install pyglpainter

Usage
The test directory of the source repository provides a full integration example,
which can also be run for testing.
Most of the time, calls to item_create() are enough to build a 3D world with objects
in it (the name for these objects here is "items"). Items can be rendered using different shader
programs.
Mouse Navigation
Left Button drag left/right/up/down: Rotate camera left/right/up/down
Middle Button drag left/right/up/down: Move camera left/right/up/down
Wheel rotate up/down: Move camera ahead/back
Right Button drag up/down: Move camera ahead/back (same as wheel)
One particular choice was to hold the camera's field of view constant; "Zooming" can be achieved by
moving the camera forward along its look axis.
Requirements

The Python version is specified in the file .python-version
OpenGL version 2.1 (with GLSL version 1.20)

Development
Dependencies are managed using pipenv:
pip install pipenv --user
pipenv install --dev

To run the example:
PYTHONPATH=src pipenv run ./test/example.py

Building
pipenv run make build_deps
pipenv run make dist