public static VertexBuffer Create<T>(ReadOnlySpan<T> data, ReadOnlySpan<VertexBufferElement> layout) where T : unmanaged
{
uint vertexBufferId;
OpenGl3Native.GenerateBuffers(1, &vertexBufferId);
var vertexBuffer = new VertexBuffer(vertexBufferId);
vertexBuffer.Bind();
fixed (T* dataPointer = data)
OpenGl3Native.BufferData(glArrayBuffer, data.Length * sizeof(T), dataPointer, glStaticDraw);
nuint offset = 0;
for (uint i = 0; i < layout.Length; i++)
{
var element = layout[(int)i];
var typeSize = element.Type switch
{
OpenGlType.Float => sizeof(float),
_ => throw new ArgumentOutOfRangeException()
};
var size = element.Count * typeSize;
OpenGl3Native.VertexAttributePointer(i, element.Count, (int)element.Type, glFalse, size, offset);
OpenGl3Native.EnableVertexAttributeArray(i);
offset += (nuint)size;
}
vertexBuffer.Unbind();
return vertexBuffer;
}
public static VertexArray Create()
{
uint vertexArrayId;
OpenGl3Native.GenerateVertexArrays(1, &vertexArrayId);
return(new VertexArray(vertexArrayId));
}
public static unsafe void Main()
{
using (new ExitHandler.LifetimeHandle())
{
const int glfwTrue = 1;
const int glfwFalse = 0;
const int glfwContextVersionMajor = 0x00022002;
const int glfwContextVersionMinor = 0x00022003;
const int glfwOpenGlProfile = 0x00022008;
const int glfwOpenGlCoreProfile = 0x00032001;
const int glfwOpenGlForwardCompat = 0x00022006;
const int glfwResizable = 0x00020003;
const int glColorBufferBit = 0x00004000;
const int glTriangles = 0x0004;
GlfwNative.Init();
GlfwNative.WindowHint(glfwContextVersionMajor, 3);
GlfwNative.WindowHint(glfwContextVersionMinor, 3);
GlfwNative.WindowHint(glfwOpenGlProfile, glfwOpenGlCoreProfile);
GlfwNative.WindowHint(glfwOpenGlForwardCompat, glfwTrue);
GlfwNative.WindowHint(glfwResizable, glfwFalse);
using (var window = new Window("Poltergeist Editor"))
{
using (var vertexArray = VertexArray.Create())
{
vertexArray.Bind();
Span <float> vertices = stackalloc float[]
{
-0.5f, -0.5f, 0.0f,
0.5f, -0.5f, 0.0f,
0.0f, 0.5f, 0.0f
};
Span <VertexBufferElement> layout = stackalloc VertexBufferElement[]
{
new VertexBufferElement(OpenGlType.Float, 3)
};
using (VertexBuffer.Create <float>(vertices, layout)) { }
while (window.IsOpen)
{
window.PollEvents();
OpenGl3Native.ClearColor(0.3f, 0.3f, 0.3f, 1.0f);
OpenGl3Native.Clear(glColorBufferBit);
OpenGl3Native.DrawArrays(glTriangles, 0, 3);
window.SwapBuffers();
}
vertexArray.Unbind();
}
}
GlfwNative.Terminate();
}
}
}
}
public void Dispose()
{
fixed (uint* vertexBufferIdPointer = &_vertexBufferId)
OpenGl3Native.DeleteBuffers(1, vertexBufferIdPointer);
}
public void Unbind()
{
OpenGl3Native.BindBuffer(glArrayBuffer, 0);
}
public void Bind()
{
OpenGl3Native.BindBuffer(glArrayBuffer, _vertexBufferId);
}
public void Dispose()
{
fixed(uint *vertexArrayIdPointer = &_vertexArrayId)
OpenGl3Native.DeleteVertexArrays(1, vertexArrayIdPointer);
}
public void Unbind()
{
OpenGl3Native.BindVertexArray(0);
}
public void Bind()
{
OpenGl3Native.BindVertexArray(_vertexArrayId);
}