Custom drawing doesn't work

[Hirashi3630]

I tried recreating what imgui_demo.cpp shows

ImGui.Begin(WindowName, ref IsWindowOpen, ImGuiWindowFlags.None);

ImDrawListPtr drawList = ImGui.GetWindowDrawList();

drawList.AddRect(new Vector2(10,10), new Vector2(20, 20), 1973790, 0.0f, ImDrawFlags.None, 2); 

ImGui.End();

but no luck... I'm not sure if I'm doing something wrong or if it's a bug.

Unity 2020.3.25.f1 ImGUI 1.84 WIP uimgui 4.1.0

[psydack]

Hello there.

Sorry, at the moment I'm trying to make a version to MacOS, so I don't have access to a windows OS and I can't test.

The syntax looks fine. What's happening? Nothing?

Could you test the code below please?

private void OnLayout(UImGui.UImGui obj)
{
    if (!ImGui.Begin("Draw list", ref isOpen)) return;

    var drawList = ImGui.GetWindowDrawList();
    drawList.AddRectFilled(Vector2.zero, Vector2.one * 10, 6528);
    drawList.AddRectFilled(Vector2.one, Vector2.one * 20, 4278190335);
    drawList.AddRectFilled(ImGui.GetCursorPos(), ImGui.GetCursorPos() * 10, 16711680);
    drawList.AddRectFilled(ImGui.GetCursorPos() * - 10, ImGui.GetCursorPos(), 4278190335);

    ImGui.End();
}

[Hirashi3630]

Sure thing! Thanks for looking into this!

I tried your code but nothing seems appear.

for some reason ImGui.ShowDemoWindow() custom drawing example works just fine though

[psydack]

I don't know if it's necessary to use ImGui.InvisibleButton().

I just replicate the whole code showwing the gradient on custom rendering window.

if (!ImGui.Begin("Draw list", ref isOpen)) return;

ImGui.PushItemWidth(-ImGui.GetFontSize() * 15);
var drawList = ImGui.GetWindowDrawList();

ImGui.Text("Gradients");
var gradientSize = new Vector2(ImGui.CalcItemWidth(), ImGui.GetFrameHeight());

//gradient 1
{
    var p0 = ImGui.GetCursorScreenPos();
    var p1 = new Vector2(p0.x + gradientSize.x, p0.y + gradientSize.y);
    var colorA = ImGui.GetColorU32(new Vector4(0, 0, 0, 255));
    var colorB = ImGui.GetColorU32(new Vector4(255, 255, 255, 255));
    drawList.AddRectFilledMultiColor(p0, p1, colorA, colorB, colorB, colorA);
    ImGui.InvisibleButton("##gradient1", gradientSize);
}

// gradient 2
{
    var p0 = ImGui.GetCursorScreenPos();
    var p1 = new Vector2(p0.x + gradientSize.x, p0.y + gradientSize.y);
    var colorA = ImGui.GetColorU32(new Vector4(0, 255, 0, 255));
    var colorB = ImGui.GetColorU32(new Vector4(255, 0, 0, 255));
    drawList.AddRectFilledMultiColor(p0, p1, colorA, colorB, colorB, colorA);
    ImGui.InvisibleButton("##gradient2", gradientSize);
}

const float sz = 36f;
const float spacing = 10f;
const float value = sz + spacing;
ImGui.Dummy(new Vector2(value * 10.2f, value * 3.0f));
ImGui.PopItemWidth();
ImGui.End();

I never tried to do custom rendering stuffs. It appears to be a bug. Later this month I probably have a functional cimgui working on mac. So, after that I will give a shoot to go deeper.

Thanks for reporting it.

[Hirashi3630]

It seems to need ImGui.InvisibleButton() to render properly

Anyway I will try to play with it more and keep you updated if I make it work!

Cheers!

[psydack]

Nice. Awesome to know that works. In the end wasn’t a bug .

;)