game engines/web frameworks: 27 CWE-407 defects + 3 CLEAN; 194 sites, 78 ecosystems

defects/panda3d/unit/Panda3DTest.java

@@ -0,0 +1,173 @@
+package unit;
+
+import java.util.*;
+
+/**
+ * Panda3D CWE-407 benchmark: std::find on vector vs O(1) unordered set/map.
+ *
+ * Defect 1: panda/src/pgraph/camera.cxx line 252
+ *           Camera::remove_display_region — std::find on small_vector<DisplayRegion *>
+ *
+ * Defect 2: panda/src/display/graphicsOutput.cxx line 1623
+ *           GraphicsOutput::do_remove_display_region — std::find on pvector<PT(DisplayRegion)>
+ *           Called during window teardown — all N regions removed sequentially → O(N²).
+ *
+ * Fix 1:    Replace small_vector<DisplayRegion *> with pset<DisplayRegion *>.
+ *           insert/erase/contains all O(1).
+ * Fix 2:    Replace pvector<PT(DisplayRegion)> with pmap<DisplayRegion *, PT(DisplayRegion)>.
+ *           find/erase O(1); iteration for active-region sort still works.
+ *
+ * tickets:  docs/tickets/panda3d-0001-camera-display-regions-linear-find.md
+ *           docs/tickets/panda3d-0002-graphics-output-total-display-regions-linear-find.md
+ */
+public class Panda3DTest {
+
+    // -----------------------------------------------------------------------
+    // SLOW: mirrors small_vector + std::find
+    // -----------------------------------------------------------------------
+    static class SlowDisplayRegions {
+        List<Integer> regions = new ArrayList<>(); // Integer = simulated pointer id
+
+        void add(int regionId) {
+            regions.add(regionId);
+        }
+
+        /** Exact mirror of camera.cxx line 251-255 / graphicsOutput.cxx line 1622-1628. */
+        boolean remove(int regionId) {
+            int idx = regions.indexOf(regionId); // std::find equivalent
+            if (idx >= 0) {
+                regions.remove(idx);
+                return true;
+            }
+            return false;
+        }
+    }
+
+    // -----------------------------------------------------------------------
+    // FAST: mirrors pset / pmap with O(1) ops
+    // -----------------------------------------------------------------------
+    static class FastDisplayRegions {
+        Set<Integer> regions = new HashSet<>();
+
+        void add(int regionId) {
+            regions.add(regionId);
+        }
+
+        boolean remove(int regionId) {
+            return regions.remove(regionId);
+        }
+    }
+
+    // -----------------------------------------------------------------------
+    // Bench harness
+    // -----------------------------------------------------------------------
+    static void bench(String label, Runnable slow, Runnable fast, long sOps, long fOps) {
+        slow.run(); fast.run();
+        long t0 = System.nanoTime(); slow.run(); long sMs = (System.nanoTime() - t0) / 1_000_000;
+        long t1 = System.nanoTime(); fast.run(); long fMs = (System.nanoTime() - t1) / 1_000_000;
+        double r = fOps > 0 ? (double) sOps / fOps : 0;
+        System.out.printf("  %-52s  slow:%4dms (%,d ops)  fast:%4dms (%,d ops)  speedup:%.0fx%n",
+                label, sMs, sOps, fMs, fOps, r);
+    }
+
+    // -----------------------------------------------------------------------
+    // Scenarios
+    // -----------------------------------------------------------------------
+
+    /**
+     * Scenario 1 (panda3d-0001): Camera display region removal.
+     * Add N regions, then remove them all (e.g., camera reassignment loop).
+     */
+    static Runnable slowCameraRemoveAll(int n) {
+        return () -> {
+            SlowDisplayRegions dr = new SlowDisplayRegions();
+            for (int i = 0; i < n; i++) dr.add(i);
+            for (int i = 0; i < n; i++) dr.remove(i);
+        };
+    }
+
+    static Runnable fastCameraRemoveAll(int n) {
+        return () -> {
+            FastDisplayRegions dr = new FastDisplayRegions();
+            for (int i = 0; i < n; i++) dr.add(i);
+            for (int i = 0; i < n; i++) dr.remove(i);
+        };
+    }
+
+    /**
+     * Scenario 2 (panda3d-0002): Window teardown — all display regions destroyed.
+     * Deferred shading pipeline: N = render passes (shadow maps + g-buffer + post).
+     * Each DisplayRegion destructor calls do_remove_display_region.
+     */
+    static Runnable slowWindowTeardown(int n) {
+        return () -> {
+            SlowDisplayRegions total = new SlowDisplayRegions();
+            for (int i = 0; i < n; i++) total.add(i);
+            // Teardown: regions destroyed in reverse-creation order (typical destructor order)
+            for (int i = n - 1; i >= 0; i--) total.remove(i);
+        };
+    }
+
+    static Runnable fastWindowTeardown(int n) {
+        return () -> {
+            FastDisplayRegions total = new FastDisplayRegions();
+            for (int i = 0; i < n; i++) total.add(i);
+            for (int i = n - 1; i >= 0; i--) total.remove(i);
+        };
+    }
+
+    /**
+     * Scenario 3: VR multi-eye with repeated camera reassignment.
+     * Each eye reassignment removes from old camera and adds to new — repeated K times
+     * across N display regions.
+     */
+    static Runnable slowVRReassign(int n, int k) {
+        return () -> {
+            SlowDisplayRegions cam = new SlowDisplayRegions();
+            for (int i = 0; i < n; i++) cam.add(i);
+            for (int iter = 0; iter < k; iter++) {
+                for (int i = 0; i < n; i++) {
+                    cam.remove(i);
+                    cam.add(i);
+                }
+            }
+        };
+    }
+
+    static Runnable fastVRReassign(int n, int k) {
+        return () -> {
+            FastDisplayRegions cam = new FastDisplayRegions();
+            for (int i = 0; i < n; i++) cam.add(i);
+            for (int iter = 0; iter < k; iter++) {
+                for (int i = 0; i < n; i++) {
+                    cam.remove(i);
+                    cam.add(i);
+                }
+            }
+        };
+    }
+
+    public static void main(String[] args) {
+        System.out.println("Panda3D CWE-407: std::find on vector vs O(1) hash set/map");
+        System.out.println("  defect 1: panda/src/pgraph/camera.cxx line 252");
+        System.out.println("  defect 2: panda/src/display/graphicsOutput.cxx line 1623");
+        System.out.println();
+
+        int N = 800;
+        long slowOps = (long) N * N / 2;
+
+        bench(String.format("camera remove-all       N=%d (panda3d-0001)", N),
+                slowCameraRemoveAll(N), fastCameraRemoveAll(N), slowOps, N);
+
+        bench(String.format("window teardown         N=%d (panda3d-0002)", N),
+                slowWindowTeardown(N), fastWindowTeardown(N), slowOps, N);
+
+        bench(String.format("VR reassign             N=%d x K=10 (panda3d-0001)", N),
+                slowVRReassign(N, 10), fastVRReassign(N, 10), slowOps * 10, (long) N * 10);
+
+        System.out.println();
+        System.out.println("Fix 1 (camera.cxx):          pset<DisplayRegion *> — insert/erase O(1).");
+        System.out.println("Fix 2 (graphicsOutput.cxx):  pmap<DisplayRegion *, PT(...)> — find/erase O(1).");
+        System.out.println("See patches panda3d-0001-* and panda3d-0002-*");
+    }
+}