Merge pull request #477 from GeneralsOnlineDevelopmentTeam/seer/fix/partition-cell-coords

x64-dev · web-flow · commit 97b7d3abe6c9 · 2026-05-07T17:43:08.000-04:00
bugfix(partitioning): Correct cell world coordinate calculation for overlap checks
diff --git a/Generals/Code/GameEngine/Source/GameLogic/Object/PartitionManager.cpp b/Generals/Code/GameEngine/Source/GameLogic/Object/PartitionManager.cpp
@@ -1887,13 +1887,19 @@ void PartitionData::doCircleFillPrecise(Real centerX, Real centerY, Real radius)
 	ThePartitionManager->worldToCell(centerX + radius, centerY + radius, &maxCellX, &maxCellY);
 
 	Real cellSize = ThePartitionManager->getCellSize();
+	Real halfCellSize = cellSize * 0.5f;
 
 	for (Int x = minCellX; x <= maxCellX; ++x)
 	{
 		for (Int y = minCellY; y <= maxCellY; ++y)
 		{
-			Real cellWorldX = x * cellSize;
-			Real cellWorldY = y * cellSize;
+			// getCellCenterPos returns the world-space center of the cell, accounting for
+			// m_worldExtents.lo offset. Subtracting halfCellSize gives the lower-left corner,
+			// which is what doesCircleOverlapCell expects.
+			Real cellWorldX, cellWorldY;
+			ThePartitionManager->getCellCenterPos(x, y, cellWorldX, cellWorldY);
+			cellWorldX -= halfCellSize;
+			cellWorldY -= halfCellSize;
 
 			if (doesCircleOverlapCell(centerX, centerY, radius, cellWorldX, cellWorldY, cellSize))
 			{
diff --git a/GeneralsMD/Code/GameEngine/Source/GameLogic/Object/PartitionManager.cpp b/GeneralsMD/Code/GameEngine/Source/GameLogic/Object/PartitionManager.cpp
@@ -1891,13 +1891,19 @@ void PartitionData::doCircleFillPrecise(Real centerX, Real centerY, Real radius)
 	ThePartitionManager->worldToCell(centerX + radius, centerY + radius, &maxCellX, &maxCellY);
 
 	Real cellSize = ThePartitionManager->getCellSize();
+	Real halfCellSize = cellSize * 0.5f;
 
 	for (Int x = minCellX; x <= maxCellX; ++x)
 	{
 		for (Int y = minCellY; y <= maxCellY; ++y)
 		{
-			Real cellWorldX = x * cellSize;
-			Real cellWorldY = y * cellSize;
+			// getCellCenterPos returns the world-space center of the cell, accounting for
+			// m_worldExtents.lo offset. Subtracting halfCellSize gives the lower-left corner,
+			// which is what doesCircleOverlapCell expects.
+			Real cellWorldX, cellWorldY;
+			ThePartitionManager->getCellCenterPos(x, y, cellWorldX, cellWorldY);
+			cellWorldX -= halfCellSize;
+			cellWorldY -= halfCellSize;
 
 			if (doesCircleOverlapCell(centerX, centerY, radius, cellWorldX, cellWorldY, cellSize))
 			{

Original file line number	Diff line number	Diff line change
`@@ -1887,13 +1887,19 @@ void PartitionData::doCircleFillPrecise(Real centerX, Real centerY, Real radius)`
`1887`	`1887`	`ThePartitionManager->worldToCell(centerX + radius, centerY + radius, &maxCellX, &maxCellY);`
`1888`	`1888`
`1889`	`1889`	`Real cellSize = ThePartitionManager->getCellSize();`
	`1890`	`+ Real halfCellSize = cellSize * 0.5f;`
`1890`	`1891`
`1891`	`1892`	`for (Int x = minCellX; x <= maxCellX; ++x)`
`1892`	`1893`	`{`
`1893`	`1894`	`for (Int y = minCellY; y <= maxCellY; ++y)`
`1894`	`1895`	`{`
`1895`		`- Real cellWorldX = x * cellSize;`
`1896`		`- Real cellWorldY = y * cellSize;`
	`1896`	`+ // getCellCenterPos returns the world-space center of the cell, accounting for`
	`1897`	`+ // m_worldExtents.lo offset. Subtracting halfCellSize gives the lower-left corner,`
	`1898`	`+ // which is what doesCircleOverlapCell expects.`
	`1899`	`+ Real cellWorldX, cellWorldY;`
	`1900`	`+ ThePartitionManager->getCellCenterPos(x, y, cellWorldX, cellWorldY);`
	`1901`	`+ cellWorldX -= halfCellSize;`
	`1902`	`+ cellWorldY -= halfCellSize;`
`1897`	`1903`
`1898`	`1904`	`if (doesCircleOverlapCell(centerX, centerY, radius, cellWorldX, cellWorldY, cellSize))`
`1899`	`1905`	`{`
Original file line number	Diff line number	Diff line change
`@@ -1891,13 +1891,19 @@ void PartitionData::doCircleFillPrecise(Real centerX, Real centerY, Real radius)`
`1891`	`1891`	`ThePartitionManager->worldToCell(centerX + radius, centerY + radius, &maxCellX, &maxCellY);`
`1892`	`1892`
`1893`	`1893`	`Real cellSize = ThePartitionManager->getCellSize();`
	`1894`	`+ Real halfCellSize = cellSize * 0.5f;`
`1894`	`1895`
`1895`	`1896`	`for (Int x = minCellX; x <= maxCellX; ++x)`
`1896`	`1897`	`{`
`1897`	`1898`	`for (Int y = minCellY; y <= maxCellY; ++y)`
`1898`	`1899`	`{`
`1899`		`- Real cellWorldX = x * cellSize;`
`1900`		`- Real cellWorldY = y * cellSize;`
	`1900`	`+ // getCellCenterPos returns the world-space center of the cell, accounting for`
	`1901`	`+ // m_worldExtents.lo offset. Subtracting halfCellSize gives the lower-left corner,`
	`1902`	`+ // which is what doesCircleOverlapCell expects.`
	`1903`	`+ Real cellWorldX, cellWorldY;`
	`1904`	`+ ThePartitionManager->getCellCenterPos(x, y, cellWorldX, cellWorldY);`
	`1905`	`+ cellWorldX -= halfCellSize;`
	`1906`	`+ cellWorldY -= halfCellSize;`
`1901`	`1907`
`1902`	`1908`	`if (doesCircleOverlapCell(centerX, centerY, radius, cellWorldX, cellWorldY, cellSize))`
`1903`	`1909`	`{`