Minimal ionGraphics demo using OpenGL

DemoGL-01.cpp

#include <ionWindow.h>
#include <ionGraphics.h>
#include <ionGraphicsGL.h>

using namespace ion::Graphics;


int main()
{
	Log::AddDefaultOutputs();

	SingletonPointer<CWindowManager> WindowManager;

	WindowManager->Init();
	CWindow * Window = WindowManager->CreateWindow(vec2i(640, 480), "TestGL", EWindowType::Windowed);

	//////////////////
	// Buffer Setup //
	//////////////////

	vector<f32> const Vertices{
		0.0f,  0.5f,
		0.5f, -0.5f,
		-0.5f, -0.5f
	};

	vector<u32> const Indices{
		0, 1, 2
	};

	IGraphicsAPI * GraphicsAPI = new COpenGLAPI();

	IVertexBuffer * VertexBuffer = GraphicsAPI->CreateVertexBuffer(Vertices.data(), Vertices.size());
	IIndexBuffer * IndexBuffer = GraphicsAPI->CreateIndexBuffer(Indices.data(), Indices.size(), EValueType::UnsignedInt32);
	

	//////////////////
	// Shader Setup //
	//////////////////

	string const VertexShaderSource = R"SHADER(
		#version 130
		in vec2 vPosition;
		void main()
		{
			gl_Position = vec4(vPosition, 0.0, 1.0);
		}
	)SHADER";

	string const FragmentShaderSource = R"SHADER(
		#version 130
		out vec4 outColor;
		void main()
		{
			outColor = vec4(1.0, 1.0, 1.0, 1.0);
		}
	)SHADER";

	IVertexShader * VertexShader = GraphicsAPI->CreateVertexShaderFromSource(VertexShaderSource);
	IPixelShader * PixelShader = GraphicsAPI->CreatePixelShaderFromSource(FragmentShaderSource);

	if (! VertexShader)
		std::cerr << "Failed to compile vertex shader!" << std::endl;

	if (! PixelShader)
		std::cerr << "Failed to compile pixel shader!" << std::endl;

	IShaderProgram * ShaderProgram = GraphicsAPI->CreateShaderProgram();
	ShaderProgram->SetVertexStage(VertexShader);
	ShaderProgram->SetPixelStage(PixelShader);

	SInputLayoutElement InputLayout[] =
	{
		{ "vPosition", 2, EValueType::Float },
	};
	ShaderProgram->SetInputLayout(InputLayout, ION_ARRAYSIZE(InputLayout));
	

	///////////////
	// Draw Loop //
	///////////////

	IPipelineState * PipelineState = GraphicsAPI->CreatePipelineState();
	PipelineState->SetIndexBuffer(IndexBuffer);
	PipelineState->SetVertexBuffer(VertexBuffer);
	PipelineState->SetProgram(ShaderProgram);

	IRenderTarget * RenderTarget = GraphicsAPI->GetWindowBackBuffer(Window);

	while (! WindowManager->ShouldClose())
	{
		WindowManager->PollEvents();

		RenderTarget->ClearColor();
		RenderTarget->ClearDepth();

		GraphicsAPI->Draw(PipelineState);

		Window->SwapBuffers();
	}


	/////////////
	// Cleanup //
	/////////////

	return 0;
}