# opengl_examples

**Repository Path**: sukikamo/opengl_examples

## Basic Information

- **Project Name**: opengl_examples
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2021-04-06
- **Last Updated**: 2021-04-06

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# OpenGL examples

<img src="screenshots/grass_1.png" width="200"> <img src="screenshots/shadow_mapping_2.png" width="200"> <img src="screenshots/water_1.png" width="200"> <img src="screenshots/tree_2.png" width="200"> <img src="screenshots/clouds_1.png" width="300"> <img src="screenshots/lod_terrain_2.png" width="300">


This is a list of examples done a few years ago after taking a computer graphic course to better understand opengl and apply some of the techniques read in the litterature.

Content of the repo:

- Triangle: hello world program, tests the display and the buffers
- Rotating cube: Add movement in the scene and transormation matrices
- Texture plane: Tests textures, both from an image and generated
- Sphere light: Different lightings on a sphere: Flat Goureaud and Phong with interacitvity to select the lighting type
- Terrain camera: A terrain generated with a Perlin noise in which we can navigate with either a free moving camera or a FPS-style one
- Bumpmapping: Simulates bumps on a flat surface using random Perlin noise and pixel shader
- Framebuffer: Displays the scene in a framebuffer, allowing post processing effects: gaussian blur, edge detection, etc.
- LOD Terrain: Implementation of a perlin noise terrain with simple CPU LOD implementation (using quad tree), which is dynamically updated with camera position
- Shadow mapping: Implementation of a dynamic shadow mapping using a depth buffer from the point of view of the light, smoothing techniques are applied on the shadow to make it less pixelated
- Ambient occlusion: Deferred SSAO algorithm done in the shaders which give depth in a scene, a few different algorithms are implemented
- Grass: Display 100k individual grass elements using instanced drawing and geometry shaders and make them move in the wind with a perlin noise
- Water: Reflects objects on a water surface with waves distorting the reflexion
- Sky: Displays a moving sun on a sky-sphere
- Particles: A simple particles system using instanced drawing
- Tree: Procedural generation of realistic trees using L-System
- Atmospheric scattering: implemented in a similar way as in the [GPU Gems 2 book](https://developer.nvidia.com/gpugems/GPUGems2/gpugems2_chapter16.html)
- Volumetric clouds: using combination of 3d and 2d noises and particles
- Texture filtering: use opengl to smooth textures
- Tessellation shader: implement the level of detail directly in a shader

## How to build
All of these examples have been tested on the following hardware:

- Intel HD graphics 620
- Nvidia GeForce 940MX

There were compiled on a Linux Mint 20, the needed libraries are the following:

- glfw 3.3.2
- glew 2.1.0
- devIl 1.7.8
- glm 0.9.9.7

Create a `build` folder in the example you want to build, then from the `build` folder, `cmake ..` to populate it and `make` to build the example