Add the Ellipses implementation. See : ocornut/imgui#2743

VideosWorks · Aug 29, 2019 · b52adc9 · b52adc9
1 parent f45395e
commit b52adc9
Showing 1 changed file with 45 additions and 0 deletions.
diff --git a/Sources/src/3rdparty/imgui/imgui_draw.cpp b/Sources/src/3rdparty/imgui/imgui_draw.cpp
@@ -899,6 +899,29 @@ void ImDrawList::PathArcTo(const ImVec2& centre, float radius, float a_min, floa
     }
 }
 
+void ImDrawList::PathEllipticalArcTo(const ImVec2& center, float radius_x, float radius_y, float rot, float a_min, float a_max, int num_segments)
+{
+    _Path.reserve(_Path.Size + (num_segments + 1));
+
+    const float cos_rot = ImCos(rot);
+    const float sin_rot = ImSin(rot);
+    for (int i = 0; i <= num_segments; i++)
+    for(int i = 0; i <= num_segments; i++)
+    {
+        //const float a = a_min + ((float)i / (float)num_segments) * (a_max - a_min);
+        float a = a_min + ((float)i / (float)num_segments) * (a_max - a_min);
+        ImVec2 point(center.x + ImCos(a) * radius_x, center.y + ImSin(a) * radius_y);
+        point.x -= center.x;
+        point.y -= center.y;
+        const float rel_x = (point.x * cos_rot) - (point.y * sin_rot);
+        const float rel_y = (point.x * sin_rot) + (point.y * cos_rot);
+        point.x = rel_x + center.x;
+        point.y = rel_y + center.y;
+        _Path.push_back(point);
+    }
+}
+
+
 static void PathBezierToCasteljau(ImVector<ImVec2>* path, float x1, float y1, float x2, float y2, float x3, float y3, float x4, float y4, float tess_tol, int level)
 {
     float dx = x4 - x1;
@@ -1094,6 +1117,28 @@ void ImDrawList::AddCircleFilled(const ImVec2& centre, float radius, ImU32 col,
     PathFillConvex(col);
 }
 
+void ImDrawList::AddEllipse(const ImVec2& center, float radius_x, float radius_y, ImU32 col, float rot, int num_segments, float thickness)
+{
+    if ((col & IM_COL32_A_MASK) == 0 || num_segments <= 2)
+        return;
+
+    // Because we are filling a closed shape we remove 1 from the count of segments/points
+    const float a_max = IM_PI * 2.0f * ((float)num_segments - 1.0f) / (float)num_segments;
+    PathEllipticalArcTo(center, radius_x, radius_y, rot, 0.0f, a_max, num_segments - 1);
+    PathStroke(col, true, thickness);
+}
+
+void ImDrawList::AddEllipseFilled(const ImVec2& center, float radius_x, float radius_y, ImU32 col, float rot, int num_segments)
+{
+    if((col & IM_COL32_A_MASK) == 0 || num_segments <= 2)
+        return;
+
+    // Because we are filling a closed shape we remove 1 from the count of segments/points
+    const float a_max = IM_PI * 2.0f * ((float)num_segments - 1.0f) / (float)num_segments;
+    PathEllipticalArcTo(center, radius_x, radius_y, rot, 0.0f, a_max, num_segments - 1);
+    PathFillConvex(col);
+}
+
 void ImDrawList::AddBezierCurve(const ImVec2& pos0, const ImVec2& cp0, const ImVec2& cp1, const ImVec2& pos1, ImU32 col, float thickness, int num_segments)
 {
     if ((col & IM_COL32_A_MASK) == 0)