How do I use ImGuiListClipper for drawing a flow container of tiles

[Shadowblitz16]

I am trying to simulate a scroll area and only draw the visible tiles...

                    var size  = ImGui.GetContentRegionAvail();
                    var index = 0;
                    var count = Tiles.Length;

                    var clipper = new ImGuiListClipperPtr();
                    clipper.Begin((int)(size.X * size.Y), TileSizeY);

                    for (var i=0; i<Tiles.Length; i++)
                    {
                        if (ImGui.GetItemRectMax().X < size.X) ImGui.SameLine();

                        var image = Image(Tiles[index].GetTexture(), new(1,0), new(0,1));
                        Raylib.BeginTextureMode(image);
                        Raylib.DrawRectangleLines(0,0, TileSizeX, TileSizeY, Color.WHITE);
                        Raylib.EndTextureMode();
                        index++;
                    }
                    clipper.End();

• How exactly does the .net version of the listclipper work>?
• How would I simulate a fake scroll area without looping 60000 times?
• How do I get the min and max rows and columns of the visible scroll area?

[Shadowblitz16]

ListClipperPtr crashes the program and there is no ImGuiList class to pass to it's constructor

[sonoro1234]

https://github.com/ocornut/imgui/blob/master/imgui_demo.cpp#L5658

[Shadowblitz16]

yes it crashes. Also please provide C# code when people ask for examples. ListClipper doesn't have a Begin, Step or End method only ListClipperPtr does so the c++ api is not a good reference

[TheLostTree]

Confirming that ListClipperPtr crashes for me as well :(

[TheLostTree]

Nevermind! I figured out that using this works without crashing

ImGuiListClipperPtr listClipper = new ImGuiListClipperPtr(ImGuiNative.ImGuiListClipper_ImGuiListClipper());

[ocornut]

I have also pushed a workaround on dear imgui side: https://github.com/ocornut/imgui/commit/e95d66faa8e6c0255572632f34fad97a32f680cd