1 files changed, 45 insertions, 11 deletions

diff --git a/src/magicplatform.cpp b/src/magicplatform.cpp
index e9fa940..ae6631d 100644
--- a/src/magicplatform.cpp
+++ b/src/magicplatform.cpp
@@ -33,6 +33,11 @@ class daEnMagicPlatform_c : public dEn_c {
 		void deleteTiles();
 		void updateTilePositions();
 
+		void checkVisibility();
+		void setVisible(bool shown);
+
+		bool isVisible;
+
 		int srcX, srcY;
 		int width, height;
 };
@@ -79,8 +84,8 @@ static void PhysCB3(daEnMagicPlatform_c *one, dStageActor_c *two, bool unkMaybeN
 	if (two->stageActorType != 1)
 		return;
 
-	// if left/right
-	if (one->moveDirection <= 1)
+	// if up/down
+	if (one->moveDirection > 1)
 		return;
 
 	if (unkMaybeNotBool) {
@@ -157,6 +162,8 @@ int daEnMagicPlatform_c::onDelete() {
 int daEnMagicPlatform_c::onExecute() {
 	handleMovement();
 
+	checkVisibility();
+
 	updateTilePositions();
 	physics.update();
 
@@ -308,8 +315,6 @@ void daEnMagicPlatform_c::findSourceArea() {
 
 
 void daEnMagicPlatform_c::createTiles() {
-	TileRenderer::List *list = dBgGm_c::instance->getTileRendererList(0);
-
 	rendererCount = width * height;
 	renderers = new TileRenderer[rendererCount];
 
@@ -326,7 +331,6 @@ void daEnMagicPlatform_c::createTiles() {
 				TileRenderer *r = &renderers[rendererID];
 				r->tileNumber = *pExistingTile;
 				r->z = pos.z;
-				list->add(r);
 			}
 
 			worldX += 16;
@@ -340,12 +344,7 @@ void daEnMagicPlatform_c::createTiles() {
 
 void daEnMagicPlatform_c::deleteTiles() {
 	if (renderers != 0) {
-		TileRenderer::List *list = dBgGm_c::instance->getTileRendererList(0);
-
-		for (int i = 0; i < rendererCount; i++) {
-			if (renderers[i].isInList())
-				list->remove(&renderers[i]);
-		}
+		setVisible(false);
 
 		delete[] renderers;
 		renderers = 0;
@@ -377,3 +376,38 @@ void daEnMagicPlatform_c::updateTilePositions() {
 
 
 
+void daEnMagicPlatform_c::checkVisibility() {
+	float effectiveLeft = pos.x, effectiveRight = pos.x + (width * 16.0f);
+	float effectiveBottom = pos.y - (height * 16.0f), effectiveTop = pos.y;
+
+	ClassWithCameraInfo *cwci = ClassWithCameraInfo::instance;
+
+	float screenRight = cwci->screenLeft + cwci->screenWidth;
+	float screenBottom = cwci->screenTop - cwci->screenHeight;
+
+	bool isOut = (effectiveLeft > screenRight) ||
+		(effectiveRight < cwci->screenLeft) ||
+		(effectiveTop < screenBottom) ||
+		(effectiveBottom > cwci->screenTop);
+
+	setVisible(!isOut);
+}
+
+void daEnMagicPlatform_c::setVisible(bool shown) {
+	if (isVisible == shown)
+		return;
+	isVisible = shown;
+
+	TileRenderer::List *list = dBgGm_c::instance->getTileRendererList(0);
+
+	for (int i = 0; i < rendererCount; i++) {
+		if (shown) {
+			if (!renderers[i].isInList() && renderers[i].tileNumber > 0)
+				list->add(&renderers[i]);
+		} else {
+			if (renderers[i].isInList())
+				list->remove(&renderers[i]);
+		}
+	}
+}
+