/// <summary>Get the height of the lowest ground position we can stand at at the given XZ coordinates, in some given Y range.</summary>
/// <returns>The resulting height, or WorldPhysics.MaximumHeight if it did not fit</returns>
public static int LowestValidGroundHeight(ref CharacterPhysicsInfo info, WorldPhysics world, int x, int z, int startY, int endY, bool staticOnly = false)
{
int startX = x + info.startX;
int endX = x + info.endX;
if (endY > WorldPhysics.MaximumHeight)
{
endY = WorldPhysics.MaximumHeight;
}
// Repeatedly test the walkable height upwards, until it returns somewhere we are confirmed to fit
int tryingHeight = startY;
int resultingHeight;
do
{
resultingHeight = world.GetGroundHeightInXRange(startX, endX, z, tryingHeight, tryingHeight + info.height, info.owner, staticOnly);
if (resultingHeight <= startY)
{
return(startY);
}
if (resultingHeight == tryingHeight)
{
break;
}
tryingHeight = resultingHeight;
}while(resultingHeight < endY);
if (resultingHeight == tryingHeight && resultingHeight >= startY && resultingHeight < endY)
{
return(resultingHeight);
}
return(WorldPhysics.MaximumHeight); // <- Failed
}
public static void TryMoveVertical(ref CharacterPhysicsInfo info, WorldPhysics world, int deltaY, ref Position position, bool staticOnly = false)
{
//
// Move on Y axis first...
//
if (deltaY < 0)
{
int groundHeight = GroundHeight(ref info, world, position, staticOnly);
if (position.Y > groundHeight) // Don't move down further if already below ground
{
int newY = position.Y + deltaY;
if (newY < groundHeight) // Don't go below ground
{
position.Y = groundHeight;
}
else
{
position.Y = newY;
}
}
}
else if (deltaY > 0)
{
int startY = position.Y + info.height;
int endY = startY + deltaY;
endY = world.GetCeilingHeightInXRange(position.X + info.startX, position.X + info.endX, position.Z, startY, endY, info.owner, staticOnly);
position.Y = endY - info.height;
}
}
/// <summary>Get the height of the topmost ground at a given position. Used for generating navigation data. (Eventually replace with a multi-layer heightmap.)</summary>
public static int TopmostGroundHeight(ref CharacterPhysicsInfo info, WorldPhysics world, int x, int z, bool staticOnly = false)
{
int startX = x + info.startX;
int endX = x + info.endX;
// Hack: If we slip in just under the ceiling, we can get the result for the next-highest floor
// This is a hack because it depends on knowledge of what GetGroundHeightInXRange is doing
int minCeiling = WorldPhysics.MaximumHeight + info.height;
if (world.levelCeiling != null)
{
for (int xx = startX; xx < endX; xx++)
{
int c = world.levelCeiling[xx, z];
if (c == 0)
{
continue;
}
if (c < minCeiling)
{
minCeiling = c;
}
}
}
return(world.GetGroundHeightInXRange(startX, endX, z, minCeiling - info.height, minCeiling, info.owner, staticOnly));
}
public static int GroundHeight(ref CharacterPhysicsInfo info, WorldPhysics world, Position position, bool staticOnly = false)
{
int startX = position.X + info.startX;
int endX = position.X + info.endX;
return(world.GetGroundHeightInXRange(startX, endX, position.Z, position.Y, position.Y + info.height, info.owner, staticOnly));
}
private static bool MoveStep(ref CharacterPhysicsInfo info, WorldPhysics world, int deltaX, int deltaZ, ref bool groundSnap, ref Position position, bool staticOnly = false)
{
int groundHeight = GroundHeight(ref info, world, new Position(position.X + deltaX, position.Y, position.Z + deltaZ), staticOnly);
// NOTE: This ensures that we cannot get kicked up later on in the method, when we set to groundHeight
if (position.Y + info.stairStepMaxHeight < groundHeight)
{
return(false); // Cannot move up that high
}
position.X += deltaX;
position.Z += deltaZ;
if (position.Y < groundHeight)
{
// TODO: BUG: We need to know if we're going to hit the ceiling by moving upwards here!
// Do not go below ground
position.Y = groundHeight;
}
else if (groundSnap)
{
if (position.Y < groundHeight + info.stairStepMaxHeight)
{
// Snap to the ground if we are nearby
position.Y = groundHeight;
}
else
{
// We came "off" the ground, stop trying to snap to it
groundSnap = false;
}
}
return(true);
}
public static bool TryMoveHorizontalDidHitWall(ref CharacterPhysicsInfo info, WorldPhysics world, int deltaX, int deltaZ, bool groundSnap, ref Position position, bool staticOnly = false)
{
bool hitWall = false;
//
// Sweep on XZ plane (slow but safe)...
//
while (deltaX > 0)
{
deltaX--;
if (!MoveStep(ref info, world, 1, 0, ref groundSnap, ref position, staticOnly))
{
hitWall = true;
goto doneX;
}
}
while (deltaX < 0)
{
deltaX++;
if (!MoveStep(ref info, world, -1, 0, ref groundSnap, ref position, staticOnly))
{
hitWall = true;
goto doneX;
}
}
doneX:
while (deltaZ > 0)
{
deltaZ--;
if (!MoveStep(ref info, world, 0, 1, ref groundSnap, ref position, staticOnly))
{
hitWall = true;
goto doneZ;
}
}
while (deltaZ < 0)
{
deltaZ++;
if (!MoveStep(ref info, world, 0, -1, ref groundSnap, ref position, staticOnly))
{
hitWall = true;
goto doneZ;
}
}
doneZ:
return(hitWall);
}
/// <summary>Get the height of the level walkable heightmap at this position, if it is flat, otherwise WorldPhysics.MaximumHeight</summary>
public static int LevelOnlyFlatGround(ref CharacterPhysicsInfo info, WorldPhysics world, int x, int z)
{
if (world.levelHeightmap == null)
{
return(WorldPhysics.MaximumHeight);
}
int startX = x + info.startX;
int endX = x + info.endX;
int h = world.levelHeightmap[startX, z];
for (int xx = startX + 1; xx < endX; xx++)
{
int c = world.levelHeightmap[xx, z];
if (c != h)
{
return(WorldPhysics.MaximumHeight);
}
}
return(h);
}
/// <summary>Determine whether a position is on (or inside) the ground at a given position.</summary>
public static bool OnGround(ref CharacterPhysicsInfo info, WorldPhysics world, Position position)
{
return(position.Y <= GroundHeight(ref info, world, position));
}
public static bool DoLemmingsMotion(ref CharacterPhysicsInfo info, WorldPhysics world, int inputX, int inputZ, int deltaX, int deltaZ, bool groundSnap, bool wallSlide, ref Position position)
{
Debug.Assert(Math.Abs(inputX) <= 1 && Math.Abs(inputZ) <= 1);
bool resultX = true, resultZ = true;
// WARNING: Delicate copy-paste code ahead (for each direction: X+, X-, Z+, Z-)
while (deltaX > 0)
{
if (MoveStep(ref info, world, 1, 0, ref groundSnap, ref position))
{
deltaX--;
}
else if (wallSlide) // Move failed, try wall-slide
{
if (inputX > 0 && inputZ <= 0 && MoveStep(ref info, world, 1, -1, ref groundSnap, ref position))
{
deltaX--;
if (deltaZ < 0)
{
deltaZ++;
}
else if (deltaX > 0)
{
deltaX--;
}
}
else if (inputX > 0 && inputZ >= 0 && MoveStep(ref info, world, 1, 1, ref groundSnap, ref position))
{
deltaX--;
if (deltaZ > 0)
{
deltaZ--;
}
else if (deltaX > 0)
{
deltaX--;
}
}
else
{
resultX = false;
goto doneX; // Failed to move on the X axis
}
}
else
{
resultX = false;
goto doneX; // Failed to move on the X axis
}
}
while (deltaX < 0)
{
if (MoveStep(ref info, world, -1, 0, ref groundSnap, ref position))
{
deltaX++;
}
else if (wallSlide) // Move failed, try wall-slide
{
if (inputX < 0 && inputZ <= 0 && MoveStep(ref info, world, -1, -1, ref groundSnap, ref position))
{
deltaX++;
if (deltaZ < 0)
{
deltaZ++;
}
else if (deltaX < 0)
{
deltaX++;
}
}
else if (inputX < 0 && inputZ >= 0 && MoveStep(ref info, world, -1, 1, ref groundSnap, ref position))
{
deltaX++;
if (deltaZ > 0)
{
deltaZ--;
}
else if (deltaX < 0)
{
deltaX++;
}
}
else
{
resultX = false;
goto doneX; // Failed to move on the X axis
}
}
else
{
resultX = false;
goto doneX; // Failed to move on the X axis
}
}
doneX:
while (deltaZ > 0)
{
if (MoveStep(ref info, world, 0, 1, ref groundSnap, ref position))
{
deltaZ--;
}
else if (wallSlide) // Move failed, try wall-slide
{
if (inputZ > 0 && inputX <= 0 && MoveStep(ref info, world, -1, 1, ref groundSnap, ref position))
{
deltaZ--;
if (deltaX < 0)
{
deltaX++;
}
else if (deltaZ > 0)
{
deltaZ--;
}
}
else if (inputZ > 0 && inputX >= 0 && MoveStep(ref info, world, 1, 1, ref groundSnap, ref position))
{
deltaZ--;
if (deltaX > 0)
{
deltaX--;
}
else if (deltaZ > 0)
{
deltaZ--;
}
}
else
{
resultZ = false;
goto doneZ; // Failed to move on the Z axis
}
}
else
{
resultZ = false;
goto doneZ; // Failed to move on the Z axis
}
}
while (deltaZ < 0)
{
if (MoveStep(ref info, world, 0, -1, ref groundSnap, ref position))
{
deltaZ++;
}
else if (wallSlide) // Move failed, try wall-slide
{
if (inputZ < 0 && inputX <= 0 && MoveStep(ref info, world, -1, -1, ref groundSnap, ref position))
{
deltaZ++;
if (deltaX < 0)
{
deltaX++;
}
else if (deltaZ < 0)
{
deltaZ++;
}
}
else if (inputZ < 0 && inputX >= 0 && MoveStep(ref info, world, 1, -1, ref groundSnap, ref position))
{
deltaZ++;
if (deltaX > 0)
{
deltaX--;
}
else if (deltaZ < 0)
{
deltaZ++;
}
}
else
{
resultZ = false;
goto doneZ; // Failed to move on the Z axis
}
}
else
{
resultZ = false;
goto doneZ; // Failed to move on the Z axis
}
}
doneZ:
return((resultX && inputX != 0) || (resultZ && inputZ != 0) || (inputX == 0 && inputZ == 0));
}
public static void TryMove(ref CharacterPhysicsInfo info, WorldPhysics world, Position delta, bool groundSnap, ref Position position, bool staticOnly = false)
{
TryMoveVertical(ref info, world, delta.Y, ref position, staticOnly);
TryMoveHorizontalDidHitWall(ref info, world, delta.X, delta.Z, groundSnap, ref position, staticOnly);
}