Computer Graphics with OpenGL and Python

This set of examples illustrate different computer graphics concepts in 2D and 3D while using: Python, OpenGL core profile, GLFW and Numpy.

Raster

ex_color_palette.py

Simulating an indirect color scheme with matplotlib

ex_color_palette_anim.py

Animation changing the color palette while simulating an indirect color scheme with matplotlib

ex_sira_direct.py

Using a direct color scheme with sira

ex_sira_indirect.py

Using an indirect color scheme with sira

OpenGL Basics

opengl_version.py

Sample code to determine OpenGL version available on the current machine. It attempts to set OpenGL core profile 3.3.

ex_triangle.py

Hello OpenGL!

ex_quad.py

Drawing a Quad via a EBO

ex_cube.py

Drawing a simple cube with OpenGL

ex_stream_draw.py

Drawing a deformable shape using GL_STREAM_DRAW

Transformations

ex_transform_polygon.py

Drawing and transforming polygons with matplotlib

ex_cpu_transforms.py

Transforming vertices in the CPU to create shapes.

ex_4shapes.py

Drawing 4 shapes with different transformations

ex_transformations_showcase.py

Ilustrating different transformations

ex_quad_controlled.py

Controlling the movement of a quad

ex_transform_imgui.py

Simple example using ImGui with GLFW and OpenGL

More info at: https://pypi.org/project/imgui/

Installation: pip install imgui[glfw]

Another example: https://github.com/swistakm/pyimgui/blob/master/doc/examples/integrations_glfw3.py#L2

ex_mouse.py

Interactions with keyboard and mouse via GLFW/python

More information at: https://www.glfw.org/docs/latest/input_guide.html

How to convert GLFW/C calls to GLFW/python https://pypi.org/project/glfw/

Textures

ex_texture_boo.py

Textures and transformations in 2D

ex_texture_quad.py

Texture Quad in 2D

ex_mipmap.py

Using mipmaps

ex_binding_textures.py

Using 2 different textures in the same Fragment Shader

ex_text_renderer.py

Example drawing text with OpenGL textures

Scene Graphs

ex_scene_graph_2dcars.py

Drawing many cars in 2D using scene_graph2

ex_scene_graph_snowman.py

Drawing a Snowman using scene_graph

Curves

ex_curves.py

Hermite and Bezier curves using python, numpy and matplotlib

3D World

ex_projections.py

Projections example

ex_texture_dice.py

Textures and transformations in 3D

ex_height_plotter.py

plotting a 2d function as a surface

ex_scene_graph_3dcars.py

Drawing 3D cars via scene graph

ex_mix2d3d.py

Example drawing 2D over a 3D world. The trick is to not clear the color buffer after drawing 3D, and then draw 2D with the shader.

If it is required to draw 3D over 2D, you may need to clear the depth buffer with glClear(GL_DEPTH_BUFFER_BIT)

ex_surface.py

Bezier Surface using python, numpy and matplotlib

Shading and Lighting

ex_lighting.py

Showing lighting effects: Flat, Gauraud and Phong

ex_lighting_texture2.py

Showing lighting effects over two textured objects: Flat, Gauraud and Phong

ex_obj_reader.py

Rendering a OBJ file simplified

Meshes

ex_delaunay.py

Using Delaunay triangluation from the scipy library

documentation: https://docs.scipy.org/doc/scipy-0.14.0/reference/generated/scipy.spatial.Delaunay.html

ex_triangle_mesh.py

Face based data structure for a triangle mesh

ex_triangle_mesh_builder.py

Using the dedicated face based triangle mesh builder

ex_openmesh_pyramid.py

Using OpenMesh to compute normals for lighting effects

Physics and Collisions

ex_collisions.py

Circles, collisions and gravity

Advanced OpenGL

ex_geometry_shader.py

Geometry Shader Basic Example

Adapted from: https://learnopengl.com/code_viewer_gh.php?code=src/4.advanced_opengl/9.1.geometry_shader_houses/geometry_shader_houses.cpp

ex_render_to_texture.py

Render to Texture Example