feat(udpscope): BSP pane tree with split, close and hit-testing

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-08-27 19:42:09 +02:00
parent c1029a25df
commit 0e5d103e73
4 changed files with 443 additions and 0 deletions
@@ -0,0 +1,169 @@
+#include "PaneTree.h"
+
+#include <gtest/gtest.h>
+
+using namespace udpscope;
+
+namespace {
+
+const Rect kScreen{0.0, 0.0, 1000.0, 600.0};
+
+std::vector<PaneTree::Placed> leavesOf(const PaneTree& tree, const Rect& area) {
+    std::vector<PaneTree::Placed>   leaves;
+    std::vector<PaneTree::Splitter> splitters;
+    tree.layout(area, leaves, splitters);
+    return leaves;
+}
+
+} /* namespace */
+
+TEST(PaneTree, StartsAsOneEmptyLeafFillingTheArea) {
+    PaneTree tree;
+    EXPECT_EQ(tree.leafCount(), 1u);
+
+    const auto leaves = leavesOf(tree, kScreen);
+    ASSERT_EQ(leaves.size(), 1u);
+    EXPECT_DOUBLE_EQ(leaves[0].rect.w, 1000.0);
+    EXPECT_DOUBLE_EQ(leaves[0].rect.h, 600.0);
+    EXPECT_TRUE(leaves[0].leaf->signals.empty());
+}
+
+TEST(PaneTree, SplittingIntoColumnsHalvesTheWidth) {
+    PaneTree tree;
+    tree.splitLeaf(tree.root(), Orient::Columns);
+
+    const auto leaves = leavesOf(tree, kScreen);
+    ASSERT_EQ(leaves.size(), 2u);
+    EXPECT_DOUBLE_EQ(leaves[0].rect.w, 500.0);
+    EXPECT_DOUBLE_EQ(leaves[1].rect.w, 500.0);
+    EXPECT_DOUBLE_EQ(leaves[0].rect.h, 600.0);
+    EXPECT_DOUBLE_EQ(leaves[1].rect.x, 500.0);
+}
+
+TEST(PaneTree, SplittingIntoRowsHalvesTheHeight) {
+    PaneTree tree;
+    tree.splitLeaf(tree.root(), Orient::Rows);
+
+    const auto leaves = leavesOf(tree, kScreen);
+    ASSERT_EQ(leaves.size(), 2u);
+    EXPECT_DOUBLE_EQ(leaves[0].rect.h, 300.0);
+    EXPECT_DOUBLE_EQ(leaves[1].rect.y, 300.0);
+    EXPECT_DOUBLE_EQ(leaves[0].rect.w, 1000.0);
+}
+
+// The pane being split keeps its content; the new pane is the empty one.
+TEST(PaneTree, SplitKeepsTheOriginalContentInTheFirstChild) {
+    PaneTree tree;
+    tree.root()->signals.push_back(Assignment{"Voltage", Color{}, 1.5f, VScale{}});
+    tree.splitLeaf(tree.root(), Orient::Columns);
+
+    const auto leaves = leavesOf(tree, kScreen);
+    ASSERT_EQ(leaves.size(), 2u);
+    ASSERT_EQ(leaves[0].leaf->signals.size(), 1u);
+    EXPECT_EQ(leaves[0].leaf->signals[0].signalName, "Voltage");
+    EXPECT_TRUE(leaves[1].leaf->signals.empty());
+}
+
+TEST(PaneTree, ClosingALeafGivesItsSpaceToTheSibling) {
+    PaneTree tree;
+    tree.splitLeaf(tree.root(), Orient::Columns);
+    auto leaves = leavesOf(tree, kScreen);
+    ASSERT_EQ(leaves.size(), 2u);
+    leaves[1].leaf->signals.push_back(Assignment{"Keep", Color{}, 1.5f, VScale{}});
+
+    tree.closeLeaf(leaves[0].leaf);
+
+    EXPECT_EQ(tree.leafCount(), 1u);
+    leaves = leavesOf(tree, kScreen);
+    ASSERT_EQ(leaves.size(), 1u);
+    EXPECT_DOUBLE_EQ(leaves[0].rect.w, 1000.0);
+    ASSERT_EQ(leaves[0].leaf->signals.size(), 1u);
+    EXPECT_EQ(leaves[0].leaf->signals[0].signalName, "Keep");
+}
+
+TEST(PaneTree, RefusesToCloseTheLastLeaf) {
+    PaneTree tree;
+    tree.closeLeaf(tree.root());
+    EXPECT_EQ(tree.leafCount(), 1u);
+}
+
+// A pane in the middle of a 3x3 touches no window edge. It must still be
+// splittable, which is why handles are inset inside the pane rather than
+// keyed on the window border.
+TEST(PaneTree, AnInteriorPaneIsStillSplittable) {
+    PaneTree tree;
+    tree.splitLeaf(tree.root(), Orient::Rows);          // top / bottom
+    auto leaves = leavesOf(tree, kScreen);
+    tree.splitLeaf(leaves[1].leaf, Orient::Rows);       // 3 rows
+    leaves = leavesOf(tree, kScreen);
+    ASSERT_EQ(leaves.size(), 3u);
+
+    PaneNode* middle = leaves[1].leaf;
+    tree.splitLeaf(middle, Orient::Columns);
+    leaves = leavesOf(tree, kScreen);
+    tree.splitLeaf(leaves[2].leaf, Orient::Columns);
+
+    EXPECT_EQ(tree.leafCount(), 5u);
+}
+
+TEST(PaneTree, LayoutReportsOneSplitterPerSplitNode) {
+    PaneTree tree;
+    tree.splitLeaf(tree.root(), Orient::Columns);
+    auto leaves = leavesOf(tree, kScreen);
+    tree.splitLeaf(leaves[0].leaf, Orient::Rows);
+
+    std::vector<PaneTree::Placed>   out;
+    std::vector<PaneTree::Splitter> splitters;
+    tree.layout(kScreen, out, splitters);
+
+    EXPECT_EQ(out.size(), 3u);
+    EXPECT_EQ(splitters.size(), 2u);
+}
+
+TEST(PaneTree, RatioSurvivesALayoutRoundTrip) {
+    PaneTree tree;
+    tree.splitLeaf(tree.root(), Orient::Columns);
+    tree.setRatio(tree.root(), 0.25);
+
+    const auto leaves = leavesOf(tree, kScreen);
+    ASSERT_EQ(leaves.size(), 2u);
+    EXPECT_DOUBLE_EQ(leaves[0].rect.w, 250.0);
+    EXPECT_DOUBLE_EQ(leaves[1].rect.w, 750.0);
+}
+
+TEST(PaneTree, RatioIsClampedSoNeitherPaneGoesBelowTheMinimum) {
+    PaneTree tree;
+    tree.splitLeaf(tree.root(), Orient::Columns);
+    tree.setRatio(tree.root(), 0.001);
+
+    const auto leaves = leavesOf(tree, kScreen);
+    EXPECT_GE(leaves[0].rect.w, kMinPaneSize);
+    EXPECT_GE(leaves[1].rect.w, kMinPaneSize);
+}
+
+TEST(PaneTree, HitTestFindsTheSplitterBetweenTwoPanes) {
+    PaneTree tree;
+    tree.splitLeaf(tree.root(), Orient::Columns);
+
+    std::vector<PaneTree::Placed>   leaves;
+    std::vector<PaneTree::Splitter> splitters;
+    tree.layout(kScreen, leaves, splitters);
+    ASSERT_EQ(splitters.size(), 1u);
+
+    const PaneTree::Splitter* hit = tree.hitTestSplitter(splitters, 500.0, 300.0);
+    ASSERT_NE(hit, nullptr);
+    EXPECT_EQ(hit->orient, Orient::Columns);
+
+    EXPECT_EQ(tree.hitTestSplitter(splitters, 100.0, 300.0), nullptr);
+}
+
+TEST(PaneTree, HitTestFindsInsetSplitHandlesAndTheCloseButton) {
+    const Rect pane{0.0, 0.0, 400.0, 300.0};
+
+    EXPECT_EQ(PaneTree::hitTestHandle(pane, 8.0, 150.0),  Handle::Left);
+    EXPECT_EQ(PaneTree::hitTestHandle(pane, 392.0, 150.0), Handle::Right);
+    EXPECT_EQ(PaneTree::hitTestHandle(pane, 200.0, 8.0),   Handle::Top);
+    EXPECT_EQ(PaneTree::hitTestHandle(pane, 200.0, 292.0), Handle::Bottom);
+    EXPECT_EQ(PaneTree::hitTestHandle(pane, 392.0, 8.0),   Handle::Close);
+    EXPECT_EQ(PaneTree::hitTestHandle(pane, 200.0, 150.0), Handle::None);
+}