OpenGL margin alignment issue

[crener]

Describe the bug
When creating an OpenGL context (using Avalonia.OpenGL.Controls.OpenGlControlBase) with margin the position of the control is offset so that it moves to the bottom right corner of the control area rather than the center like I would expect.

To Reproduce
Steps to reproduce the behavior:

1. Create new project
2. Create an OpenGL control (inherit from Avalonia.OpenGL.Controls.OpenGlControlBase) - See example control
3. Add the OpenGL to the main window and set a margin like this Margin="30"
4. Make sure you have .With(new Win32PlatformOptions { UseWgl = true }) in the AppBuilder Config
5. Start program

OpenGL Control:

using System;
using Avalonia;
using Avalonia.Media;
using Avalonia.OpenGL;

namespace OpenGLIssue.Views;

public class OpenGLControl : Avalonia.OpenGL.Controls.OpenGlControlBase, IAffectsRender
{
    public event EventHandler? Invalidated;

    public OpenGLControl()
    {
    }

    protected override Size MeasureOverride(Size availableSize)
    {
        InvalidateVisual();
        return new Size(availableSize.Width, Math.Min(availableSize.Width, availableSize.Height));
    }

    protected override void OnOpenGlRender(GlInterface gl, int frameBuffer)
    {
        gl.Clear(16384);
    }
    
    protected override void OnOpenGlInit(GlInterface gl, int fb)
    {
        gl.ClearColor(1f, 192 / 255f, 202 / 255f, 1f);
    }

    protected override void OnOpenGlDeinit(GlInterface gl, int fb)
    {
    }
}

MainWindow:

<Window xmlns="https://github.com/avaloniaui"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:vm="using:OpenGLIssue.ViewModels"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:views="clr-namespace:OpenGLIssue.Views"
        mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
        x:Class="OpenGLIssue.Views.MainWindow"
        Icon="/Assets/avalonia-logo.ico"
        Title="OpenGLIssue"
        Width="300" Height="300">

    <Design.DataContext>
        <vm:MainWindowViewModel/>
    </Design.DataContext>

    <views:OpenGLControl 
        Margin="30"/>

</Window>

Expected behavior
Looking at the second screenshot I would expect it to render inside the blue area rather than being offset as that is where the margin says it should be

Screenshots

This is how it looks when rendering but using the Dev tools to render actual control size you can see that the OpenGL control isn't correctly positioned.

Desktop (please complete the following information):

• OS: Windows 10 Pro 10.0.19043 Build 19043
• Version 0.10.13, 0.10.14

Additional context
Add any other context about the problem here.

[maxkatz6]

As @kekekeks suggested, draw image call is invalid. Should be

            context.DrawImage(_bitmap, new Rect(_bitmap.Size), new Rect(Bounds.Size));

https://github.com/AvaloniaUI/Avalonia/blob/master/src/Avalonia.OpenGL/Controls/OpenGlControlBase.cs#L37

[jp2masa]

This was fixed in #8728, then the control was reworked on #10014, I tested it now and it works fine. This can be closed.