Line broken issue when using D3D11_FILTER_MIN_MAG_MIP_POINT filter in the sampler

[zaafar]

Version/Branch of Dear ImGui:

Version: 1.88 WIP
Branch: master

Back-end/Renderer/Compiler/OS

Back-ends: imgui_impl_dx11.cpp
Operating System: windows 10
Graphic Card: RTX 2080 (Nvidia)

My Issue/Question:
Hi, I am from the .net C# world and I have already figured out how to solve this issue. All details can be found here: ImGuiNET/ImGui.NET#261 (sorry for making you visit another url to understand the issue).

The reason I am opening this issue over here is to make sure that this is the intended behaviour and/or not in the scope of this library. If that's the case then sorry for wasting your time and feel free to close the issue.

Screenshots/Video/Steps to reproduce
Following is the patch you can apply to this repository to re-produce the issue. After applying this patch, please run example_win32_directx11 example.

index a7407d66..2e5c70e5 100644
--- a/backends/imgui_impl_dx11.cpp
+++ b/backends/imgui_impl_dx11.cpp
@@ -352,7 +352,7 @@ static void ImGui_ImplDX11_CreateFontsTexture()
     {
         D3D11_SAMPLER_DESC desc;
         ZeroMemory(&desc, sizeof(desc));
-        desc.Filter = D3D11_FILTER_MIN_MAG_MIP_LINEAR;
+        desc.Filter = D3D11_FILTER_MIN_MAG_MIP_POINT;
         desc.AddressU = D3D11_TEXTURE_ADDRESS_WRAP;
         desc.AddressV = D3D11_TEXTURE_ADDRESS_WRAP;
         desc.AddressW = D3D11_TEXTURE_ADDRESS_WRAP;
diff --git a/examples/example_win32_directx11/main.cpp b/examples/example_win32_directx11/main.cpp
index 8dc486a4..b163fcdf 100644
--- a/examples/example_win32_directx11/main.cpp
+++ b/examples/example_win32_directx11/main.cpp
@@ -107,7 +107,13 @@ int main(int, char**)
         {
             static float f = 0.0f;
             static int counter = 0;
-
+            float x = 0.0f;
+            float y = 619.500f;
+            float w = 351.0f;
+            float h = 248.0f;
+            ImVec2 p = ImVec2(x, y);
+            ImVec2 q = ImVec2(x + w, y + h);
+            ImGui::GetBackgroundDrawList()->AddRect(p, q, 0xFFFFFFFF);
             ImGui::Begin("Hello, world!");                          // Create a window called "Hello, world!" and append into it.

             ImGui::Text("This is some useful text.");               // Display some text (you can use a format strings too)

==when using D3D11_FILTER_MIN_MAG_MIP_LINEAR==

==when using D3D11_FILTER_MIN_MAG_MIP_POINT==

[ocornut]

Our texture-based path for anti-aliasing (#3245) indeed do requires linear sampling.

Before building the atlas:

io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines;

Would lift that constraint.

I am now going to add extra comments to clarify that requirement.
EDIT There are comments e.g.

bool        AntiAliasedLinesUseTex;     // Enable anti-aliased lines/borders using textures where possible. Require backend to render with bilinear filtering. Latched at the beginning of the frame (copied to ImDrawList).

But certainly more would be good.

Thank you.

[ocornut]

Pushed f7f3047

[zaafar]

nice! it's amazing to see those comments. thank you for the amazing lib and amazing support. :)
Also, i validate that by using that flag the issue is gone.