C#•3mo ago

✅ ImGui.NET and OpenTK

hello, i tried to render a basic imgui window on my opentk window, but it just dont works and crash with an exception

using System;
using ImGuiNET;
using OpenTK;
using OpenTK.Graphics;
using OpenTK.Graphics.OpenGL4;
using OpenTK.Mathematics;
using OpenTK.Windowing.Common;
using OpenTK.Windowing.Desktop;

namespace ImGuiWithOpenTK
{
    class Program
    {
        private static GameWindow gameWindow;

        public static void Main(string[] args)
        {
            NativeWindowSettings nativeWindowSettings = new NativeWindowSettings
            {
                Size = new Vector2i(800, 600),
                Title = "ImGui with OpenTK",
                API = ContextAPI.OpenGL,
                APIVersion = new Version(4, 6),
            };

            GameWindowSettings gameWindowSettings = new GameWindowSettings
            {
                UpdateFrequency = 60
            };

            gameWindow = new GameWindow(gameWindowSettings, nativeWindowSettings);

            gameWindow.Load += GameWindow_Load;

            gameWindow.RenderFrame += GameWindow_RenderFrame;

            gameWindow.UpdateFrame += GameWindow_UpdateFrame;

            gameWindow.Run();
        }

        private static void GameWindow_UpdateFrame(FrameEventArgs obj)
        {

        }

        private static void GameWindow_RenderFrame(FrameEventArgs obj)
        {
            GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);

            ImGui.NewFrame();
            ImGui.Begin("Demo windows");
            ImGui.Text("Hello world");
            ImGui.End();
            ImGui.Render();

            gameWindow.SwapBuffers();
        }

        private static void GameWindow_Load()
        {
            GL.ClearColor(Color4.CornflowerBlue);

            ImGui.CreateContext();
            ImGuiIOPtr io = ImGui.GetIO();
            ImGui.StyleColorsDark();
        }
    }
}

using System;
using ImGuiNET;
using OpenTK;
using OpenTK.Graphics;
using OpenTK.Graphics.OpenGL4;
using OpenTK.Mathematics;
using OpenTK.Windowing.Common;
using OpenTK.Windowing.Desktop;

namespace ImGuiWithOpenTK
{
    class Program
    {
        private static GameWindow gameWindow;

        public static void Main(string[] args)
        {
            NativeWindowSettings nativeWindowSettings = new NativeWindowSettings
            {
                Size = new Vector2i(800, 600),
                Title = "ImGui with OpenTK",
                API = ContextAPI.OpenGL,
                APIVersion = new Version(4, 6),
            };

            GameWindowSettings gameWindowSettings = new GameWindowSettings
            {
                UpdateFrequency = 60
            };

            gameWindow = new GameWindow(gameWindowSettings, nativeWindowSettings);

            gameWindow.Load += GameWindow_Load;

            gameWindow.RenderFrame += GameWindow_RenderFrame;

            gameWindow.UpdateFrame += GameWindow_UpdateFrame;

            gameWindow.Run();
        }

        private static void GameWindow_UpdateFrame(FrameEventArgs obj)
        {

        }

        private static void GameWindow_RenderFrame(FrameEventArgs obj)
        {
            GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);

            ImGui.NewFrame();
            ImGui.Begin("Demo windows");
            ImGui.Text("Hello world");
            ImGui.End();
            ImGui.Render();

            gameWindow.SwapBuffers();
        }

        private static void GameWindow_Load()
        {
            GL.ClearColor(Color4.CornflowerBlue);

            ImGui.CreateContext();
            ImGuiIOPtr io = ImGui.GetIO();
            ImGui.StyleColorsDark();
        }
    }
}

35 Replies

Silme94•3mo ago

Fatal error. System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
Repeat 2 times:
--------------------------------
   at ImGuiNET.ImGuiNative.igNewFrame()
--------------------------------
   at ImGuiNET.ImGui.NewFrame()
   at ImGuiWithOpenTK.Program.GameWindow_RenderFrame(OpenTK.Windowing.Common.FrameEventArgs)
   at OpenTK.Windowing.Desktop.GameWindow.OnRenderFrame(OpenTK.Windowing.Common.FrameEventArgs)
   at OpenTK.Windowing.Desktop.GameWindow.Run()
   at ImGuiWithOpenTK.Program.Main(System.String[])

Fatal error. System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
Repeat 2 times:
--------------------------------
   at ImGuiNET.ImGuiNative.igNewFrame()
--------------------------------
   at ImGuiNET.ImGui.NewFrame()
   at ImGuiWithOpenTK.Program.GameWindow_RenderFrame(OpenTK.Windowing.Common.FrameEventArgs)
   at OpenTK.Windowing.Desktop.GameWindow.OnRenderFrame(OpenTK.Windowing.Common.FrameEventArgs)
   at OpenTK.Windowing.Desktop.GameWindow.Run()
   at ImGuiWithOpenTK.Program.Main(System.String[])

TheRanger•3mo ago

ah yes good thing im here cuz i did make it work but that error seems new to me Shouldnt you have an instance of a ImGuiController ?

Silme94•3mo ago

ImGuiController is not definied on ImGui.NET bro

TheRanger•3mo ago

never said it does

Silme94•3mo ago

its from github or smth? is there a way to make without?

TheRanger•3mo ago

let me check actually imguicontroller is there

TheRanger•3mo ago

https://github.com/ImGuiNET/ImGui.NET

GitHub

GitHub - ImGuiNET/ImGui.NET: An ImGui wrapper for .NET.

An ImGui wrapper for .NET. Contribute to ImGuiNET/ImGui.NET development by creating an account on GitHub.

TheRanger•3mo ago

did you follow the tutorial? there's an example project there called SampleProgram try running it

Silme94•3mo ago

ok yeah but i dont wanna paste it bro i wanna write myself

TheRanger•3mo ago

the controller?

Silme94•3mo ago

how do we actually use it cause i see also Memory.cs MemoryEditor

TheRanger•3mo ago

this is specialized for opentk https://github.com/aybe/DearImGui

GitHub

GitHub - aybe/DearImGui: imgui & implot for .NET & OpenTK

imgui & implot for .NET & OpenTK. Contribute to aybe/DearImGui development by creating an account on GitHub.

Silme94•3mo ago

there is no way to use the normal ImGui.NET library? how do u do for example on ur projects

TheRanger•3mo ago

ah yes sorry this is the one im actually using https://github.com/NogginBops/ImGui.NET_OpenTK_Sample

GitHub

GitHub - NogginBops/ImGui.NET_OpenTK_Sample: A sample project showi...

A sample project showing an ImGui (using ImGui.NET) renderer for OpenTK in C# - NogginBops/ImGui.NET_OpenTK_Sample

Silme94•3mo ago

i copy the controller and how i use it on my code?

TheRanger•3mo ago

to be safe use this ^ project because its the one im using so it'd probably be easier to help u the project has an example it should give you an idea how to

Silme94•3mo ago

this is working but that just look rly weird, and i cannot interacte the imgui menu with keys

TheRanger•3mo ago

use $paste

MODiX•3mo ago

If your code is too long, you can post to https://paste.mod.gg/ and copy the link into chat for others to see your shared code!

Silme94•3mo ago

using System;
using ImGuiNET;
using OpenTK;
using OpenTK.Graphics;
using OpenTK.Graphics.OpenGL4;
using OpenTK.Mathematics;
using OpenTK.Windowing.Common;
using OpenTK.Windowing.Desktop;

namespace ImGuiWithOpenTK
{
    class Program
    {
        private static GameWindow gameWindow;
        private static ImGuiController _controller;

        public static void Main(string[] args)
        {
            NativeWindowSettings nativeWindowSettings = new NativeWindowSettings
            {
                Size = new Vector2i(800, 600),
                Title = "ImGui with OpenTK",
                API = ContextAPI.OpenGL,
                APIVersion = new Version(4, 6),
            };

            GameWindowSettings gameWindowSettings = new GameWindowSettings
            {
                UpdateFrequency = 60
            };

            gameWindow = new GameWindow(gameWindowSettings, nativeWindowSettings);

            _controller = new ImGuiController(800, 600);

            gameWindow.Load += GameWindow_Load;

            gameWindow.RenderFrame += GameWindow_RenderFrame;

            gameWindow.UpdateFrame += GameWindow_UpdateFrame;

            gameWindow.Run();
        }

        private static void GameWindow_UpdateFrame(FrameEventArgs obj)
        {

        }

        private static void GameWindow_RenderFrame(FrameEventArgs obj)
        {
            GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);

            _controller.Update(gameWindow, (float)obj.Time);

            ImGui.DockSpaceOverViewport();

            ImGui.ShowDemoWindow();

            _controller.Render();

            ImGuiController.CheckGLError("End of frame");

            gameWindow.SwapBuffers();
        }

        private static void GameWindow_Load()
        {
            GL.ClearColor(Color4.CornflowerBlue);
            GL.Viewport(0, 0, 800, 600);
        }
    }
}

using System;
using ImGuiNET;
using OpenTK;
using OpenTK.Graphics;
using OpenTK.Graphics.OpenGL4;
using OpenTK.Mathematics;
using OpenTK.Windowing.Common;
using OpenTK.Windowing.Desktop;

namespace ImGuiWithOpenTK
{
    class Program
    {
        private static GameWindow gameWindow;
        private static ImGuiController _controller;

        public static void Main(string[] args)
        {
            NativeWindowSettings nativeWindowSettings = new NativeWindowSettings
            {
                Size = new Vector2i(800, 600),
                Title = "ImGui with OpenTK",
                API = ContextAPI.OpenGL,
                APIVersion = new Version(4, 6),
            };

            GameWindowSettings gameWindowSettings = new GameWindowSettings
            {
                UpdateFrequency = 60
            };

            gameWindow = new GameWindow(gameWindowSettings, nativeWindowSettings);

            _controller = new ImGuiController(800, 600);

            gameWindow.Load += GameWindow_Load;

            gameWindow.RenderFrame += GameWindow_RenderFrame;

            gameWindow.UpdateFrame += GameWindow_UpdateFrame;

            gameWindow.Run();
        }

        private static void GameWindow_UpdateFrame(FrameEventArgs obj)
        {

        }

        private static void GameWindow_RenderFrame(FrameEventArgs obj)
        {
            GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);

            _controller.Update(gameWindow, (float)obj.Time);

            ImGui.DockSpaceOverViewport();

            ImGui.ShowDemoWindow();

            _controller.Render();

            ImGuiController.CheckGLError("End of frame");

            gameWindow.SwapBuffers();
        }

        private static void GameWindow_Load()
        {
            GL.ClearColor(Color4.CornflowerBlue);
            GL.Viewport(0, 0, 800, 600);
        }
    }
}

Silme94•3mo ago

the color of my windows does not infect the imgui menu why this is grey and dont resize

TheRanger•3mo ago

bro did you check the sample? where is this method

        protected override void OnResize(ResizeEventArgs e)
        {
            base.OnResize(e);

            // Update the opengl viewport
            GL.Viewport(0, 0, ClientSize.X, ClientSize.Y);

            // Tell ImGui of the new size
            _controller.WindowResized(ClientSize.X, ClientSize.Y);
        }

        protected override void OnResize(ResizeEventArgs e)
        {
            base.OnResize(e);

            // Update the opengl viewport
            GL.Viewport(0, 0, ClientSize.X, ClientSize.Y);

            // Tell ImGui of the new size
            _controller.WindowResized(ClientSize.X, ClientSize.Y);
        }

Silme94•3mo ago

yes fr but what is ClientSize where did he got that variable form

TheRanger•3mo ago

its in the sample its a property defined in the GameWindow class in your case it would be gameWindow.ClientSize.X

Silme94•3mo ago

oh ok sorry thats works but i cannot change the background color and its always grey

Silme94•3mo ago

$paste

message.txt

MODiX•3mo ago

If your code is too long, you can post to https://paste.mod.gg/ and copy the link into chat for others to see your shared code!

Silme94•3mo ago

https://paste.mod.gg/ahsxjyzdlcjj/0

BlazeBin - ahsxjyzdlcjj

A tool for sharing your source code with the world!

TheRanger•3mo ago

show image?

Silme94•3mo ago

@ @R like the screen here the same color but it scale well i just want to change color

TheRanger•3mo ago

so its all grey?

Silme94•3mo ago

yes but imgui windows work well

TheRanger•3mo ago

what color is this? GL.ClearColor(new Color4(0.0f, 0.3f, 0.5f, 1.0f)); also wow this code

            gameWindowSettings = new GameWindowSettings
            {
                UpdateFrequency = 60
            };

            gameWindowSettings = new GameWindowSettings
            {
                UpdateFrequency = 60
            };

super lags my game i just use GameWindowSettings.Default like the sample does hmm ur right i ran the sample, it doesnt change the color lol it does change in my game, ill see why found the culprit comment this line ImGui.DockSpaceOverViewport();

Silme94•3mo ago

ok that work well thanks !close

Accord•3mo ago

Closed!

Gaming

Programming

✅ ImGui.NET and OpenTK