perf(heightmap): Update terrain tiles only if the terrain draw origin has really changed (TheSuperHackers#2677)

Author: xezon

Core/GameEngineDevice/Include/W3DDevice/GameClient/WorldHeightMap.h

@@ -108,6 +108,15 @@ class WorldHeightMap : public RefCountClass,
 #define NO_EVAL_TILING_MODES
 
 public:
+
+	struct DrawArea
+	{
+		Int originX;
+		Int originY;
+		Int sizeX;
+		Int sizeY;
+	};
+
 #ifdef EVAL_TILING_MODES
 	enum {TILE_4x4, TILE_6x6, TILE_8x8} m_tileMode;
 #endif
@@ -260,6 +269,8 @@ class WorldHeightMap : public RefCountClass,
 
 	void getUVForBlend(Int edgeClass, Region2D *range);
 
+	DrawArea createDrawArea(Int xOrg, Int yOrg);
+	Bool setDrawArea(const DrawArea& drawArea);
 	Bool setDrawOrg(Int xOrg, Int yOrg);
 
 	static void freeListOfMapObjects();

Core/GameEngineDevice/Source/W3DDevice/GameClient/HeightMap.cpp

@@ -1183,15 +1183,13 @@ void HeightMapRenderObjClass::oversizeTerrain(Int tilesToOversize)
 	}
 	Int dx = width-m_map->getDrawWidth();
 	Int dy = height-m_map->getDrawHeight();
- 	m_map->setDrawWidth(width);
+	m_map->setDrawWidth(width);
 	m_map->setDrawHeight(height);
 	dx /= 2;
 	dy /= 2;
 	Int newOrgX = m_map->getDrawOrgX()-dx;
-	Int newOrgy = m_map->getDrawOrgY()-dy;
-	if (newOrgX<0) newOrgX=0;
-	if (newOrgy<0) newOrgy=0;
-	m_map->setDrawOrg(newOrgX,newOrgy);
+	Int newOrgY = m_map->getDrawOrgY()-dy;
+	m_map->setDrawOrg(newOrgX,newOrgY);
 	m_originX = 0;
 	m_originY = 0;
 	if (m_shroud)
@@ -1742,26 +1740,29 @@ void HeightMapRenderObjClass::updateCenter(CameraClass *camera , RefRenderObjLis
 	newOrgX = (visMaxX+visMinX)/2 - m_x/2.0;
 	newOrgY = (visMaxY+visMinY)/2 - m_y/2.0;
 
+	WorldHeightMap::DrawArea newDrawArea = m_map->createDrawArea(newOrgX, newOrgY);
+
 	m_updating = true;
 	if (m_needFullUpdate)
 	{
 		m_needFullUpdate = false;
-		m_map->setDrawOrg(newOrgX, newOrgY);
+		m_map->setDrawArea(newDrawArea);
 		updateBlock(0, 0, m_x-1, m_y-1, m_map, pLightsIterator);
 		m_updating = false;
 		return;
 	}
 	else
 	{
 		constexpr const Int cellOffset = 1;
-		Int deltaX = newOrgX - m_map->getDrawOrgX();
-		Int deltaY = newOrgY - m_map->getDrawOrgY();
+		const Int deltaX = newDrawArea.originX - m_map->getDrawOrgX();
+		const Int deltaY = newDrawArea.originY - m_map->getDrawOrgY();
 
 		if (IABS(deltaX) > m_x/2 || IABS(deltaY)>m_x/2) {
-			m_map->setDrawOrg(newOrgX, newOrgY);
-			m_originY = 0;
-			m_originX = 0;
-			updateBlock(0, 0, m_x-1, m_y-1, m_map, pLightsIterator);
+			if (m_map->setDrawArea(newDrawArea)) {
+				m_originY = 0;
+				m_originX = 0;
+				updateBlock(0, 0, m_x-1, m_y-1, m_map, pLightsIterator);
+			}
 			m_updating = false;
 			return;
 		}
@@ -1770,7 +1771,6 @@ void HeightMapRenderObjClass::updateCenter(CameraClass *camera , RefRenderObjLis
 			if (m_map->setDrawOrg(m_map->getDrawOrgX(), newOrgY)) {
 				Int minY = 0;
 				Int maxY = 0;
-				deltaY -= newOrgY - m_map->getDrawOrgY();
 				m_originY += deltaY;
 				if (m_originY >= m_y-1) m_originY -= m_y-1;
 				if (deltaY<0) {
@@ -1806,7 +1806,6 @@ void HeightMapRenderObjClass::updateCenter(CameraClass *camera , RefRenderObjLis
 			if (m_map->setDrawOrg(newOrgX, m_map->getDrawOrgY())) {
 				Int minX = 0;
 				Int maxX = 0;
-				deltaX -= newOrgX - m_map->getDrawOrgX();
 				m_originX += deltaX;
 				if (m_originX >= m_x-1) m_originX -= m_x-1;
 				if (deltaX<0) {

Core/GameEngineDevice/Source/W3DDevice/GameClient/WorldHeightMap.cpp

@@ -2201,43 +2201,52 @@ TerrainTextureClass *WorldHeightMap::getFlatTexture(Int xCell, Int yCell, Int ce
 }
 
 
-Bool WorldHeightMap::setDrawOrg(Int xOrg, Int yOrg)
+WorldHeightMap::DrawArea WorldHeightMap::createDrawArea(Int xOrg, Int yOrg)
 {
-	Int newX, newY;
-	Int newWidth, newHeight;
-	newX = xOrg;
-	newY = yOrg;
-	newWidth = m_drawWidthX;
-	newHeight = m_drawHeightY;
+	DrawArea area;
+	area.sizeX = m_drawWidthX;
+	area.sizeY = m_drawHeightY;
+
 	if (TheGlobalData && TheGlobalData->m_stretchTerrain) {
-		newWidth=STRETCH_DRAW_WIDTH;
-		newHeight=STRETCH_DRAW_HEIGHT;
+		area.sizeX = STRETCH_DRAW_WIDTH;
+		area.sizeY = STRETCH_DRAW_HEIGHT;
 	}
 	if (TheGlobalData && TheGlobalData->m_drawEntireTerrain) {
-		newWidth=m_width;
-		newHeight=m_height;
-	}
-	if (newWidth > m_width) newWidth = m_width;
-	if (newHeight > m_height) newHeight = m_height;
-	if (newX > m_width - newWidth) newX = m_width-newWidth;
-	if (newX<0) newX=0;
-	if (newY > m_height - newHeight) newY = m_height - newHeight;
-	if (newY<0) newY=0;
-	Bool anythingDifferent = (m_drawOriginX!=newX) ||
-										 (m_drawOriginY!=newY) ||
-										 (m_drawWidthX!=newWidth) ||
-										 (m_drawHeightY!=newHeight) ;
+		area.sizeX = m_width;
+		area.sizeY = m_height;
+	}
+	area.sizeX = std::min(area.sizeX, m_width);
+	area.sizeY = std::min(area.sizeY, m_height);
+	area.originX = clamp(0, xOrg, m_width - area.sizeX);
+	area.originY = clamp(0, yOrg, m_height - area.sizeY);
+
+	return area;
+}
+
+Bool WorldHeightMap::setDrawArea(const DrawArea& area)
+{
+	Bool anythingDifferent =
+		m_drawOriginX != area.originX ||
+		m_drawOriginY != area.originY ||
+		m_drawWidthX != area.sizeX ||
+		m_drawHeightY != area.sizeY;
 
 	if (anythingDifferent) {
-		m_drawOriginX=newX;
-		m_drawOriginY=newY;
-		m_drawWidthX=newWidth;
-		m_drawHeightY=newHeight;
-		return(true);
+		m_drawOriginX = area.originX;
+		m_drawOriginY = area.originY;
+		m_drawWidthX = area.sizeX;
+		m_drawHeightY = area.sizeY;
+		return true;
 	}
-	return(false);
+	return false;
+}
+
+Bool WorldHeightMap::setDrawOrg(Int xOrg, Int yOrg)
+{
+	return setDrawArea(createDrawArea(xOrg, yOrg));
 }
 
+
 /** Gets global texture class. */
 Int WorldHeightMap::getTextureClass(Int xIndex, Int yIndex, Bool baseClass)
 {