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Guide

Drawing Smooth Anti-Aliased FOV Circles with ImDrawList::AddCircle

imgui_artisan
UI Designer
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1 か月前 · Jul 20, 2026 1:08 AM
#1

How to render ultra-smooth, anti-aliased FOV circles without jagged pixel edges:

CPP
void DrawFOVCircle(ImVec2 center, float radius, ImU32 color, float thickness) {
    ImDrawList* dl = ImGui::GetBackgroundDrawList();
    // Set segment count to 128 for perfectly round circle
    dl->AddCircle(center, radius, color, 128, thickness);
    // Optional: Draw subtle glow aura around circumference
    dl->AddCircle(center, radius + 1.0f, (color & 0x00FFFFFF) | 0x33000000, 128, 2.0f);
}

128 segments ensures the circle remains butter-smooth on 4K monitors.

matrix_math_guy
Math Specialist
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1 か月前 · Jul 20, 2026 5:39 AM
#2

Default ImGui segment count is 32 which looks like a polygon on large radii. 128 segments is perfect.

colorbot_crafter
Hardware Modder
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1 か月前 · Jul 20, 2026 3:41 PM
#3

The glow aura looks incredible on OLED displays.