Circe

Circe is a minimalist framework that can be used in OpenGL (and soon Vulkan) based applications. Circe serves as a boiler-plate solution for your graphics applications, so you don't spend time with the basics. The goal is to achieve results with fewer lines of code, but also allowing great flexibility. In principle, circe should allow experienced users to control advanced features, while allowing less experienced users to make use of it as well.

This library is my personal lib that I use in my projects, at my own risk :) Please keep it in mind.

Here is what Circe can provide to you with ease:

	some features
rendering	shadow map, texture maps, hdr, pbr, deferred rendering, ssbos, uniform buffers
scene	instancing, built-in shapes, GPU picking
UI	imgui included, profiler view, console output, gizmo, file dialog

very old ancient blog: http://aergia.weebly.com/

Usage

Please check the docs for a good introduction, details of the API and examples.

For a quick preview, the example bellow creates a blank window of size 800x800:

#include <circe/circe.h>

// Circe provides a BaseApp class to help you quickly setup an application
// Just inherit from it and override some methods
class HelloCirce :
public circe::gl::BaseApp {
public:
  HelloCirce() : BaseApp(800, 800, "Hello Circe Window Title") {
  }
  // the render method is the only method required to override,
  // all other methods are optional
  void render(circe::CameraInterface *camera) override {
    // render your stuff
  }
};

int main() {
  return HelloCirce().run();
}

Here is an example on how you can create and render your models:

// The scene model holds all the OpenGL buffers and bind them properly
circe::gl::SceneModel model;
// You can create scene models from built-in shapes for example:
// create a wireframe box
model = circe::Shapes::box(hermes::bbox3::unitBox(), circe::shape_options::wireframe);
// create a unit sphere with uv coordinates and normals
model = circe::Shapes::icosphere({0,0,0}, 1, circe::shape_options::normals |
                                             circe::shape_options::uv);
// when rendering, just call
model.draw();

Build

In order to build and use Circe (with no options), you can do as usual with cmake:

git clone https://github.com/filipecn/circe.git
cd circe
mkdir build
cd build
cmake ..
make -j8 install

Depending on what you want to compile, you may need to set some cmake options:

variable	description	default
BUILD_ALL	set all variables below to ON	OFF
USE_VULKAN	compiles with support to Vulkan	OFF
BUILD_WITH_CUDA	compiles with support to CUDA	OFF
BUILD_TESTS	build unit-tests	OFF
BUILD_EXAMPLES	build examples	OFF
BUILD_DOCS	generates documentation	OFF

Suppose you would like to use VULKAN and build the examples, your cmake command then will look like this:

cmake .. -DUSE_VULKAN=ON -DBUILD_EXAMPLES=ON

Please check the docs for details about the build process of circe.

I've been developing Circe under Ubuntu 20.04 and Nvidia, I have no idea how it behaves on other configurations.

Dependencies

All dependencies are handled by cmake or have been included into the source, so there is no need to get them yourself.

• hermes - for all the basics
• GLFW - for window management and user input
• imgui - for user interface
• stb - for image files and text fonts
• tinyobjloader - for reading/writing obj files
• glad - for handling OpenGL extension functions

TODO

• create cmake variables for dependencies

Contact

Please feel free to contact me by e-mail :)