maxortner01 / midnight-graphics

Midnight Graphics

Functionality

Window and Event Handling

A Graphics::Window represents an OS window and its surface. Currently, it is a single buffer: There is only one thread which blocks to wait for the previous frame to finish rendering. It's event handling is done with window.pollEvent(event) where Graphics::Event event. The event contains a variant which itself represents the current event off the event stack. There are various ways of handling this process nicely, though I prefer to make a functor:

struct EventHandler
{
    mn::Graphics::Window& window;

	EventVisitor(mn::Graphics::Window& w) :
		window(w)
	{	}

	template<typename T>
	void operator() (T value) const
	{	}

	void operator() (mn::Graphics::Event::Quit)
	{
		window.close();
	}

    ...
};

which can be used with std::visit(e_handler, event.event) inside the poll event loop.

Shader and Data

In order to actually draw things you first need the data you want to render and then the specification for how to draw that data. The former is a Graphics::Buffer and the latter your Graphics::Pipeline.

To create a buffer, the best way is to utilize the Graphics::TypeBuffer:

struct Vertex
{
	Math::Vec2f position;
	float rotation;
};

Graphics::TypeBuffer<Vertex> vertices;
vertices.resize(3);
vertices[0] = ...
...

To create a pipeline, we use a Graphics::PipelineBuilder. Check out the documentation for more info on that, but I always have preferred to use Lua scripts to create the pipeline. So it's as simple as

auto pipeline = Graphics::PipelineBuilder(SOURCE_DIR, "/main.lua")
					.build()

Then, to draw we simply

auto rf = window.startFrame();

rf.clear({ 0.f, 0.f, 0.f });
rf.startRender();
rf.draw(pipeline, vertices);
rf.endRender();

window.endFrame(rf);