修复频谱图bug

render_2D/plottable/Spectrum.cpp

@@ -490,7 +490,7 @@ void Spectrum_Control::paint_partition(Painter& painter, int partition_index) {
     const auto& partition = output.partitions[static_cast<std::size_t>(partition_index)];
     const auto view = render_state_view();
     const auto& state = render_properties(view);
-    painter.clip(partition.clip);
+    const auto clip = painter.scoped_clip(partition.clip);
     paint_curve(painter, partition.maximum, state.max_pen, state.max_brush);
     paint_curve(painter, partition.minimum, state.min_pen, state.min_brush);
     paint_curve(painter, partition.current, state.current_pen, state.current_brush);

render_2D/render/Blend2D_Cache.cpp

@@ -222,11 +222,22 @@ Painter::~Painter() {
         context_.end();
 }
 
-void Painter::clip(RectF value) {
+Painter::Clip_Scope::Clip_Scope(Painter& painter, RectF value) {
     value = value.normalized();
-    if (!active_ || value.empty())
+    if (!painter.active_ || value.empty())
         return;
-    context_.clip_to_rect(BLRect(value.x, value.y, value.width, value.height));
+    painter.context_.save();
+    painter.context_.clip_to_rect(BLRect(value.x, value.y, value.width, value.height));
+    painter_ = &painter;
+}
+
+Painter::Clip_Scope::~Clip_Scope() {
+    if (painter_)
+        painter_->context_.restore();
+}
+
+Painter::Clip_Scope Painter::scoped_clip(RectF value) {
+    return Clip_Scope(*this, value);
 }
 
 void Painter::composite(const Blend2D_Color_Cache& source) {

render_2D/render/Blend2D_Cache.h

@@ -28,13 +28,22 @@ private:
 
 class Painter {
 public:
+    class Clip_Scope {
+    public:
+        Clip_Scope(Painter& painter, RectF rect);
+        ~Clip_Scope();
+        Clip_Scope(const Clip_Scope&) = delete;
+        Clip_Scope& operator=(const Clip_Scope&) = delete;
+    private:
+        Painter* painter_{};
+    };
     Painter(Blend2D_Color_Cache& cache, Size size);
     ~Painter();
     Painter(const Painter&) = delete;
     Painter& operator=(const Painter&) = delete;
 
     [[nodiscard]] explicit operator bool() const noexcept { return active_; }
-    void clip(RectF rect);
+    [[nodiscard]] Clip_Scope scoped_clip(RectF rect);
     void composite(const Blend2D_Color_Cache& source);
     void line(PointF first, PointF second, const Pen& pen);
     void polyline(std::span<const PointF> points, const Pen& pen);

render_2D/tests/render_2D_Integration_Tests.cpp

@@ -86,6 +86,28 @@ TEST(Renderive_Core2, EveryCurveInterpolationModeHasDistinctSamplingSemantics) {
     EXPECT_LE(clipped.front().x, 0.0);
     EXPECT_GE(clipped.back().x, 100.0);
 }
+TEST(Renderive_Core2, PainterScopedClipRestoresPreviousClip) {
+    detail::Blend2D_Color_Cache cache;
+    {
+        detail::Painter painter(cache, {8, 2});
+        {
+            const auto clip = painter.scoped_clip({0.0, 0.0, 4.0, 2.0});
+            painter.rect({0.0, 0.0, 8.0, 2.0}, Pen{.style = Line_Style::None},
+                         Brush{Color::red(), Brush_Style::Solid});
+        }
+        {
+            const auto clip = painter.scoped_clip({4.0, 0.0, 4.0, 2.0});
+            painter.rect({0.0, 0.0, 8.0, 2.0}, Pen{.style = Line_Style::None},
+                         Brush{Color::green(), Brush_Style::Solid});
+        }
+    }
+    const Image_View view = cache.view();
+    ASSERT_EQ(view.width, 8);
+    ASSERT_EQ(view.height, 2);
+    const auto* row = reinterpret_cast<const Pixel*>(view.data);
+    EXPECT_EQ(row[1], pack_rgba(255, 0, 0));
+    EXPECT_EQ(row[6], pack_rgba(0, 255, 0));
+}
 TEST(Renderive_Core2, BicubicHeatmapUsesRealCubicResampling) {
     const std::array<Pixel, 16> source{
         pack_rgba(255, 0, 0), pack_rgba(0, 0, 0), pack_rgba(255, 255, 255), pack_rgba(0, 0, 255),