fix blueprint rotation bug

src/test/BlueprintTest.cpp

@@ -7,12 +7,14 @@
 #include <QPoint>
 
 #include "Blueprint.h"
+#include "BuildingsConfig.h"
 #include "BuildingSystem.h"
 #include "BuildingType.h"
 #include "ConfigLoader.h"
 #include "EntityId.h"
 #include "Rotation.h"
 #include "Simulation.h"
+#include "SurfaceMask.h"
 
 // ---------------------------------------------------------------------------
 // Helpers that mirror the production implementations under test.
@@ -87,21 +89,51 @@ static Blueprint buildBlueprint(const std::vector<BuildingSpec>& specs)
 }
 
 // Apply one CW/CCW rotation to every building in the constellation, mirroring
-// the Q / E handling in GameWorldView::keyPressEvent.
+// the corrected Q / E handling in GameWorldView::keyPressEvent.
-static void applyRotationCW(Blueprint& bp)
+// Each building's anchor is recomputed from the rotated body cells so that
+// multi-tile footprints stay correctly aligned after rotation.
+static void applyRotationCW(Blueprint& bp, const GameConfig& cfg)
 {
     for (BlueprintBuilding& bb : bp.buildings)
     {
-        bb.offset   = rotateCW(bb.offset);
+        const BuildingDef* def = nullptr;
+        for (const BuildingDef& d : cfg.buildings.buildings)
+        {
+            if (d.type == bb.type) { def = &d; break; }
+        }
+        if (!def) { continue; }
+        const ParsedSurfaceMask mask = parseSurfaceMask(def->surfaceMask, bb.rotation);
+        int minX = INT_MAX, minY = INT_MAX;
+        for (const QPoint& cell : mask.bodyCells)
+        {
+            const QPoint abs = bb.offset + cell;
+            minX = std::min(minX, -abs.y());
+            minY = std::min(minY,  abs.x());
+        }
+        bb.offset   = QPoint(minX, minY);
         bb.rotation = rotCW(bb.rotation);
     }
 }
 
-static void applyRotationCCW(Blueprint& bp)
+static void applyRotationCCW(Blueprint& bp, const GameConfig& cfg)
 {
     for (BlueprintBuilding& bb : bp.buildings)
     {
-        bb.offset   = rotateCCW(bb.offset);
+        const BuildingDef* def = nullptr;
+        for (const BuildingDef& d : cfg.buildings.buildings)
+        {
+            if (d.type == bb.type) { def = &d; break; }
+        }
+        if (!def) { continue; }
+        const ParsedSurfaceMask mask = parseSurfaceMask(def->surfaceMask, bb.rotation);
+        int minX = INT_MAX, minY = INT_MAX;
+        for (const QPoint& cell : mask.bodyCells)
+        {
+            const QPoint abs = bb.offset + cell;
+            minX = std::min(minX,  abs.y());
+            minY = std::min(minY, -abs.x());
+        }
+        bb.offset   = QPoint(minX, minY);
         bb.rotation = rotCCW(bb.rotation);
     }
 }
@@ -249,6 +281,7 @@ TEST_CASE("Blueprint: non-axis-aligned offset rotates correctly", "[blueprint]")
 
 TEST_CASE("Blueprint: CW constellation rotation updates offset and building rotation", "[blueprint]")
 {
+    const GameConfig cfg = loadConfig();
     // Building one tile to the right, facing East.
     Blueprint bp;
     bp.name = "test";
@@ -258,7 +291,7 @@ TEST_CASE("Blueprint: CW constellation rotation updates offset and building rota
     bb.offset   = QPoint(1, 0);
     bp.buildings.push_back(bb);
 
-    applyRotationCW(bp);
+    applyRotationCW(bp, cfg);
 
     // Offset: right → down.
     REQUIRE(bp.buildings[0].offset == QPoint(0, 1));
@@ -268,6 +301,7 @@ TEST_CASE("Blueprint: CW constellation rotation updates offset and building rota
 
 TEST_CASE("Blueprint: CCW constellation rotation updates offset and building rotation", "[blueprint]")
 {
+    const GameConfig cfg = loadConfig();
     Blueprint bp;
     bp.name = "test";
     BlueprintBuilding bb;
@@ -276,7 +310,7 @@ TEST_CASE("Blueprint: CCW constellation rotation updates offset and building rot
     bb.offset   = QPoint(1, 0);
     bp.buildings.push_back(bb);
 
-    applyRotationCCW(bp);
+    applyRotationCCW(bp, cfg);
 
     // Offset: right → up.
     REQUIRE(bp.buildings[0].offset == QPoint(0, -1));
@@ -286,6 +320,7 @@ TEST_CASE("Blueprint: CCW constellation rotation updates offset and building rot
 
 TEST_CASE("Blueprint: four CW rotations restore offset and building rotation", "[blueprint]")
 {
+    const GameConfig cfg = loadConfig();
     Blueprint bp;
     bp.name = "test";
     BlueprintBuilding bb;
@@ -297,7 +332,7 @@ TEST_CASE("Blueprint: four CW rotations restore offset and building rotation", "
     const QPoint   originalOffset   = bb.offset;
     const Rotation originalRotation = bb.rotation;
 
-    for (int i = 0; i < 4; ++i) { applyRotationCW(bp); }
+    for (int i = 0; i < 4; ++i) { applyRotationCW(bp, cfg); }
 
     REQUIRE(bp.buildings[0].offset   == originalOffset);
     REQUIRE(bp.buildings[0].rotation == originalRotation);
@@ -305,6 +340,7 @@ TEST_CASE("Blueprint: four CW rotations restore offset and building rotation", "
 
 TEST_CASE("Blueprint: multi-building constellation rotates symmetrically CW", "[blueprint]")
 {
+    const GameConfig cfg = loadConfig();
     // Two buildings left and right of center; after CW they should be above and below.
     Blueprint bp;
     bp.name = "test";
@@ -315,7 +351,7 @@ TEST_CASE("Blueprint: multi-building constellation rotates symmetrically CW", "[
     right.offset = QPoint( 1, 0);
     bp.buildings = { left, right };
 
-    applyRotationCW(bp);
+    applyRotationCW(bp, cfg);
 
     // left  (-1, 0) → CW → (0, -1)  (above center)
     // right ( 1, 0) → CW → (0,  1)  (below center)
@@ -325,6 +361,80 @@ TEST_CASE("Blueprint: multi-building constellation rotates symmetrically CW", "[
     REQUIRE(bp.buildings[1].rotation == Rotation::South);
 }
 
+// ---------------------------------------------------------------------------
+// Regression: multi-tile building rotation (the anchor-offset-only bug)
+// ---------------------------------------------------------------------------
+
+TEST_CASE("Blueprint: CW rotation keeps belt adjacent to miner output port", "[blueprint]")
+{
+    const GameConfig cfg = loadConfig();
+
+    // East miner: anchor (0,0), body cells (0,0),(1,0),(0,1).
+    // Output port indicator '>' at (1,1) → port tile (1,1), direction East.
+    // Belt placed at (1,1) — the port exit tile.
+    // Constellation body cells: {(0,0),(1,0),(0,1),(1,1)}.
+    // Integer center: ((0+1)/2, (0+1)/2) = (0,0).
+    // Miner offset (0,0), belt offset (1,1).
+    Blueprint bp;
+    bp.name = "test";
+    BlueprintBuilding miner;
+    miner.type     = BuildingType::Miner;
+    miner.rotation = Rotation::East;
+    miner.offset   = QPoint(0, 0);
+    BlueprintBuilding belt;
+    belt.type     = BuildingType::Belt;
+    belt.rotation = Rotation::East;
+    belt.offset   = QPoint(1, 1);   // port exit tile of East miner relative to its anchor
+    bp.buildings  = { miner, belt };
+
+    applyRotationCW(bp, cfg);
+
+    // Miner body cells (0,0),(1,0),(0,1) rotated CW: (0,0),(0,1),(-1,0).
+    // New miner anchor = min(-1..0, 0..1) = (-1, 0).
+    REQUIRE(bp.buildings[0].offset   == QPoint(-1, 0));
+    REQUIRE(bp.buildings[0].rotation == Rotation::South);
+
+    // Belt body cell (1,1) rotated CW: (-1, 1). New belt anchor = (-1, 1).
+    REQUIRE(bp.buildings[1].offset   == QPoint(-1, 1));
+    REQUIRE(bp.buildings[1].rotation == Rotation::South);
+
+    // South miner port tile relative to its anchor is (0,1) (the 'v' indicator in ["AA","vA"]).
+    // Miner anchor in constellation = (-1,0). Port exit = (-1,0)+(0,1) = (-1,1) = belt anchor. ✓
+    REQUIRE(bp.buildings[1].offset == bp.buildings[0].offset + QPoint(0, 1));
+}
+
+TEST_CASE("Blueprint: CCW rotation keeps belt adjacent to miner output port", "[blueprint]")
+{
+    const GameConfig cfg = loadConfig();
+
+    Blueprint bp;
+    bp.name = "test";
+    BlueprintBuilding miner;
+    miner.type     = BuildingType::Miner;
+    miner.rotation = Rotation::East;
+    miner.offset   = QPoint(0, 0);
+    BlueprintBuilding belt;
+    belt.type     = BuildingType::Belt;
+    belt.rotation = Rotation::East;
+    belt.offset   = QPoint(1, 1);
+    bp.buildings  = { miner, belt };
+
+    applyRotationCCW(bp, cfg);
+
+    // Miner body cells (0,0),(1,0),(0,1) rotated CCW: (0,0),(0,-1),(1,0).
+    // New miner anchor = min(0..1, -1..0) = (0, -1).
+    REQUIRE(bp.buildings[0].offset   == QPoint(0, -1));
+    REQUIRE(bp.buildings[0].rotation == Rotation::North);
+
+    // Belt body cell (1,1) rotated CCW: (1,-1). New belt anchor = (1,-1).
+    REQUIRE(bp.buildings[1].offset   == QPoint(1, -1));
+    REQUIRE(bp.buildings[1].rotation == Rotation::North);
+
+    // North miner port tile relative to its anchor is (1,0) (the '^' indicator in ["A^","AA"]).
+    // Miner anchor in constellation = (0,-1). Port exit = (0,-1)+(1,0) = (1,-1) = belt anchor. ✓
+    REQUIRE(bp.buildings[1].offset == bp.buildings[0].offset + QPoint(1, 0));
+}
+
 // ---------------------------------------------------------------------------
 // Simulation-level: blueprint placement places buildings at correct tiles
 // ---------------------------------------------------------------------------

src/ui/GameWorldView.cpp

@@ -2,6 +2,7 @@
 
 #include <algorithm>
 #include <cctype>
+#include <climits>
 #include <cmath>
 #include <map>
 #include <string>
@@ -936,7 +937,17 @@ void GameWorldView::keyPressEvent(QKeyEvent* event)
         {
             for (BlueprintBuilding& bb : m_blueprintMode->buildings)
             {
-                bb.offset   = QPoint(-bb.offset.y(), bb.offset.x());
+                const BuildingDef* def = findBuildingDef(bb.type);
+                if (!def) { continue; }
+                const ParsedSurfaceMask mask = parseSurfaceMask(def->surfaceMask, bb.rotation);
+                int minX = INT_MAX, minY = INT_MAX;
+                for (const QPoint& cell : mask.bodyCells)
+                {
+                    const QPoint abs = bb.offset + cell;
+                    minX = std::min(minX, -abs.y());
+                    minY = std::min(minY,  abs.x());
+                }
+                bb.offset   = QPoint(minX, minY);
                 bb.rotation = rotateClockwise(bb.rotation);
             }
         }
@@ -951,7 +962,17 @@ void GameWorldView::keyPressEvent(QKeyEvent* event)
         {
             for (BlueprintBuilding& bb : m_blueprintMode->buildings)
             {
-                bb.offset   = QPoint(bb.offset.y(), -bb.offset.x());
+                const BuildingDef* def = findBuildingDef(bb.type);
+                if (!def) { continue; }
+                const ParsedSurfaceMask mask = parseSurfaceMask(def->surfaceMask, bb.rotation);
+                int minX = INT_MAX, minY = INT_MAX;
+                for (const QPoint& cell : mask.bodyCells)
+                {
+                    const QPoint abs = bb.offset + cell;
+                    minX = std::min(minX,  abs.y());
+                    minY = std::min(minY, -abs.x());
+                }
+                bb.offset   = QPoint(minX, minY);
                 bb.rotation = rotateCounterClockwise(bb.rotation);
             }
         }