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Licar/racing.h

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/**
racing module: implements the racing physics and logic.
*/
#ifndef _LCR_RACING_H
#define _LCR_RACING_H
typedef int32_t LCR_GameUnit; ///< abstract game unit
#define LCR_GAME_UNIT 1024 ///< length of map square in LCR_GameUnits
#define LCR_RACING_INPUT_FORW 0x01
#define LCR_RACING_INPUT_RIGHT 0x02
#define LCR_RACING_INPUT_BACK 0x04
#define LCR_RACING_INPUT_LEFT 0x08
#define LCR_RACING_EVENT_CP_TAKEN 0x0001
#define LCR_RACING_EVENT_FINISHED 0x0002
#define LCR_RACING_EVENT_CRASH_SMALL 0x0004
#define LCR_RACING_EVENT_CRASH_BIG 0x0008
#define LCR_PHYSICS_UNIT 4096 ///< len. of square for phys. engine
#define TPE_RESHAPE_TENSION_LIMIT 3
#define TPE_RESHAPE_ITERATIONS 8
#include "map.h"
#include "tinyphysicsengine.h"
// TODO: move some of this to constants?
#define LCR_GRAVITY (LCR_PHYSICS_UNIT / 160)
#define LCR_FAN_FORCE 3
#define LCR_FAN_FORCE_DECREASE 6
#define LCR_CAR_FORWARD_FRICTION (TPE_F / 180)
#define LCR_CAR_AIR_FRICTION 32
#define LCR_CAR_STAND_FRICTION_MULTIPLIER 32
#define LCR_CAR_STEER_FRICTION (TPE_F)
#define LCR_CAR_ELASTICITY (TPE_F / 150)
#define LCR_CAR_ACCELERATION (LCR_PHYSICS_UNIT / 19)
#define LCR_CAR_STEER_SPEED (LCR_GAME_UNIT / 17)
#define LCR_CAR_STEER_MAX (LCR_GAME_UNIT / 2)
#define LCR_CAR_DRIFT_THRESHOLD_1 (LCR_GAME_UNIT / 4)
#define LCR_CAR_DRIFT_THRESHOLD_0 (LCR_GAME_UNIT / 200)
// multipliers (in 8ths) of friction and acceleration on concrete:
#define LCR_CAR_GRASS_FACTOR 5
#define LCR_CAR_DIRT_FACTOR 3
#define LCR_CAR_ICE_FACTOR 1
#define LCR_CAR_DRIFT_FACTOR 2 ///< only affects steering friction
#define LCR_CAR_JOINTS 5
#define LCR_CAR_CONNECTIONS 10
struct
{
TPE_World physicsWorld;
TPE_Body carBody;
TPE_Joint carJoints[LCR_CAR_JOINTS];
TPE_Connection carConnections[LCR_CAR_CONNECTIONS];
uint32_t tick;
uint8_t wheelCollisions; /**< In individual bits records for each car wheel
whether it's currently touching the ground.
Lower bits record current collisions, higher
bits the previous state (for averaging). */
TPE_Vec3 carPositions[2]; ///< Current and previous position in game units.
TPE_Vec3 carRotations[2]; ///< Current and previous rotation in game units.
uint8_t carDrifting; ///< Whether or not the car is currently in drift.
TPE_Unit fanForce; ///< Upwards acceleration caused by a fan.
LCR_GameUnit wheelAngle; ///< Current wheel angle, 0 to LCR_GAME_UNIT.
LCR_GameUnit wheelSteer; ///< Left/right steer with LCR_CAR_STEER_MAX bounds.
LCR_GameUnit carSpeed; /**< Signed speed in game units per tick (negative
if backwards) */
// for fixing physics bugs:
TPE_Vec3 carOKPositions[LCR_CAR_JOINTS];
uint8_t carNotOKCount;
} LCR_racing;
TPE_Vec3 _LCR_TPE_vec3DividePlain(TPE_Vec3 v, TPE_Unit d)
{
v.x /= d; v.y /= d; v.z /= d;
return v;
}
/**
Helper function for _LCR_racingEnvironmentFunction, returns closest point
on a map block placed at coordinate origin.
*/
TPE_Vec3 _LCR_racingBlockEnvFunc(TPE_Vec3 point, const uint8_t *block)
{
TPE_Vec3 v, vBest;
TPE_Unit d, dBest = TPE_INFINITY;
uint8_t bx, by, bz;
LCR_mapBlockGetCoords(block,&bx,&by,&bz);
TPE_Vec3 blockOffset = TPE_vec3(
(((int) bx) - LCR_MAP_SIZE_BLOCKS / 2) * LCR_PHYSICS_UNIT,
(((int) by) - LCR_MAP_SIZE_BLOCKS / 2) * (LCR_PHYSICS_UNIT / 2),
(((int) bz) - LCR_MAP_SIZE_BLOCKS / 2) * LCR_PHYSICS_UNIT);
point = TPE_vec3Minus(point,blockOffset); // shift to origin
uint8_t transform =
LCR_mapBlockOppositeTransform(LCR_mapBlockGetTransform(block));
LCR_TRANSFORM_COORDS(transform,point.x,point.y,point.z,LCR_PHYSICS_UNIT,
(LCR_PHYSICS_UNIT / 2))
point = TPE_vec3Minus(point,
TPE_vec3(LCR_PHYSICS_UNIT / 2,LCR_PHYSICS_UNIT / 4,LCR_PHYSICS_UNIT / 2));
switch (block[0])
{
case LCR_BLOCK_FULL:
case LCR_BLOCK_BOTTOM:
case LCR_BLOCK_BOTTOM_ACCEL:
case LCR_BLOCK_LEFT:
case LCR_BLOCK_BOTTOM_LEFT:
case LCR_BLOCK_BOTTOM_LEFT_FRONT:
case LCR_BLOCK_FULL_ACCEL:
case LCR_BLOCK_FULL_FAN:
{
TPE_Vec3
offset = TPE_vec3(0,0,0),
size = TPE_vec3(LCR_PHYSICS_UNIT / 2,LCR_PHYSICS_UNIT / 4,
LCR_PHYSICS_UNIT / 2);
if (block[0] == LCR_BLOCK_BOTTOM ||
block[0] == LCR_BLOCK_BOTTOM_ACCEL ||
block[0] == LCR_BLOCK_BOTTOM_LEFT ||
block[0] == LCR_BLOCK_BOTTOM_LEFT_FRONT)
{
offset.y -= LCR_PHYSICS_UNIT / 8;
size.y = LCR_PHYSICS_UNIT / 8;
}
if (block[0] == LCR_BLOCK_LEFT ||
block[0] == LCR_BLOCK_BOTTOM_LEFT ||
block[0] == LCR_BLOCK_BOTTOM_LEFT_FRONT)
{
offset.x -= LCR_PHYSICS_UNIT / 4;
size.x = LCR_PHYSICS_UNIT / 4;
}
if (block[0] == LCR_BLOCK_BOTTOM_LEFT_FRONT)
{
offset.z -= LCR_PHYSICS_UNIT / 4;
size.z = LCR_PHYSICS_UNIT / 4;
}
point = TPE_envAABox(point,offset,size);
break;
}
#define _CHECK_NEXT(check)\
v = check;\
d = TPE_dist(point,v);\
if (d < dBest) {\
vBest = v;\
dBest = d;}\
if (dBest == 0) {\
point = vBest;\
break;}
case LCR_BLOCK_RAMP_CURVED_WALL:
_CHECK_NEXT(TPE_envAABox(point,TPE_vec3(5 * LCR_PHYSICS_UNIT / 12,0,0),
TPE_vec3(LCR_PHYSICS_UNIT / 12,LCR_PHYSICS_UNIT / 4,LCR_PHYSICS_UNIT
/ 2)));
// fall through
case LCR_BLOCK_RAMP_CURVED_PLAT:
_CHECK_NEXT(TPE_envAABox(point,TPE_vec3(0,0,5 * LCR_PHYSICS_UNIT / 12),
TPE_vec3(LCR_PHYSICS_UNIT / 2,LCR_PHYSICS_UNIT / 4,LCR_PHYSICS_UNIT / 12
)));
// fall through
case LCR_BLOCK_RAMP_CURVED:
{
TPE_Unit sides[6];
TPE_Unit rampShift = block[0] != LCR_BLOCK_RAMP_CURVED ?
LCR_PHYSICS_UNIT / 6 : 0;
sides[0] = -1 * LCR_PHYSICS_UNIT / 8 - rampShift;
sides[1] = -1 * LCR_PHYSICS_UNIT / 4;
sides[2] = LCR_PHYSICS_UNIT / 2 - rampShift;
sides[3] = -1 * LCR_PHYSICS_UNIT / 4;
sides[4] = LCR_PHYSICS_UNIT / 2 - rampShift;
sides[5] = LCR_PHYSICS_UNIT / 4;
_CHECK_NEXT(TPE_envAATriPrism(point,
TPE_vec3(0,0,0),sides,LCR_PHYSICS_UNIT,2))
sides[0] = -1 * LCR_PHYSICS_UNIT / 2;
sides[1] = -1 * LCR_PHYSICS_UNIT / 4;
sides[2] = LCR_PHYSICS_UNIT / 2 - rampShift;
sides[3] = -1 * LCR_PHYSICS_UNIT / 4;
sides[4] = LCR_PHYSICS_UNIT / 2 - rampShift;
sides[5] = LCR_PHYSICS_UNIT / 8;
_CHECK_NEXT(TPE_envAATriPrism(point,TPE_vec3(0,0,0),sides,LCR_PHYSICS_UNIT
,2));
point = vBest;
break;
}
case LCR_BLOCK_CORNER_CONVEX:
case LCR_BLOCK_CORNER_CONCAVE:
{
TPE_Unit sides[6];
sides[0] = -1 * LCR_PHYSICS_UNIT / 2;
sides[1] = LCR_PHYSICS_UNIT / 2;
sides[2] = -1 * LCR_PHYSICS_UNIT / 2;
sides[3] = -1 * LCR_PHYSICS_UNIT / 2;
sides[4] = LCR_PHYSICS_UNIT / 5;
sides[5] = -1 * LCR_PHYSICS_UNIT / 5;
if (block[0] == LCR_BLOCK_CORNER_CONCAVE)
{
sides[4] *= -1;
sides[5] *= -1;
}
_CHECK_NEXT(TPE_envAATriPrism(point,TPE_vec3(0,0,0),sides,
LCR_PHYSICS_UNIT / 2,1));
sides[2] = sides[4];
sides[3] = sides[5];
sides[4] = LCR_PHYSICS_UNIT / 2;
sides[5] = LCR_PHYSICS_UNIT / 2;
_CHECK_NEXT(TPE_envAATriPrism(point,TPE_vec3(0,0,0),sides,
LCR_PHYSICS_UNIT / 2,1));
point = vBest;
break;
}
#undef _CHECK_NEXT
case LCR_BLOCK_RAMP_CORNER:
{
TPE_Unit sides[6];
sides[0] = -1 * LCR_PHYSICS_UNIT / 2;
sides[1] = -1 * LCR_PHYSICS_UNIT / 4;
sides[2] = LCR_PHYSICS_UNIT / 2;
sides[3] = -1 * LCR_PHYSICS_UNIT / 4;
sides[4] = LCR_PHYSICS_UNIT / 2;
sides[5] = LCR_PHYSICS_UNIT / 4;
if (point.x > LCR_PHYSICS_UNIT / 2)
{
sides[4] *= -1;
point = TPE_envAATriPrism(point,TPE_vec3(0,0,0),
sides,LCR_PHYSICS_UNIT,2);
}
else if (point.z < -1 * LCR_PHYSICS_UNIT / 2)
point = TPE_envAATriPrism(point,TPE_vec3(0,0,0),
sides,LCR_PHYSICS_UNIT,0);
else if (point.y < -1 * LCR_PHYSICS_UNIT / 4)
{
sides[1] *= 2;
sides[3] *= 2;
sides[5] *= 2;
point = TPE_envAATriPrism(point,
TPE_vec3(0,0,0),sides,LCR_PHYSICS_UNIT / 2,1);
}
else
{
point = TPE_envHalfPlane(point,TPE_vec3(LCR_PHYSICS_UNIT / 2,
LCR_PHYSICS_UNIT / 4,-1 * LCR_PHYSICS_UNIT / 2),
TPE_vec3(-1 * LCR_PHYSICS_UNIT,2 * LCR_PHYSICS_UNIT,LCR_PHYSICS_UNIT));
#define LINESNAP(a,b,c,d,e,f)\
point = TPE_envLineSegment(point,\
TPE_vec3(a * LCR_PHYSICS_UNIT / 2,b * LCR_PHYSICS_UNIT / 4,\
c * LCR_PHYSICS_UNIT / 2),TPE_vec3(d * LCR_PHYSICS_UNIT / 2,\
e * LCR_PHYSICS_UNIT / 4,f * LCR_PHYSICS_UNIT / 2));
if (point.y < -1 * LCR_PHYSICS_UNIT / 4)
LINESNAP(-1,-1,-1,1,-1,1)
else if (point.x > LCR_PHYSICS_UNIT / 2)
LINESNAP(1,1,-1,1,-1,1)
else if (point.z < -1 * LCR_PHYSICS_UNIT / 2)
LINESNAP(-1,-1,-1,1,1,-1)
#undef LINESNAP
}
break;
}
case LCR_BLOCK_RAMP:
case LCR_BLOCK_RAMP_34:
case LCR_BLOCK_RAMP_12:
case LCR_BLOCK_RAMP_14:
case LCR_BLOCK_RAMP_STEEP:
case LCR_BLOCK_RAMP_ACCEL:
case LCR_BLOCK_RAMP_FAN:
{
uint8_t front, top;
LCR_rampGetDimensions(block[0],&top,&front);
front = 6 - front;
TPE_Unit sides[6];
sides[0] =
-1 * LCR_PHYSICS_UNIT / 2 + (LCR_PHYSICS_UNIT / 6) * ((int) front);
sides[1] = -1 * LCR_PHYSICS_UNIT / 4;
sides[2] = LCR_PHYSICS_UNIT / 2;
sides[3] = -1 * LCR_PHYSICS_UNIT / 4;
sides[4] = LCR_PHYSICS_UNIT / 2;
sides[5] = -1 * LCR_PHYSICS_UNIT / 4 +
((int) top) * (LCR_PHYSICS_UNIT / 8);
point = TPE_envAATriPrism(point,TPE_vec3(0,0,0),sides,LCR_PHYSICS_UNIT,2);
break;
}
case LCR_BLOCK_HILL:
{
point = (point.y > -1 * LCR_PHYSICS_UNIT / 4 && point.z
< LCR_PHYSICS_UNIT / 4) ?
TPE_envCylinder(point,
TPE_vec3(0,-1 * LCR_PHYSICS_UNIT / 2,LCR_PHYSICS_UNIT / 4),
TPE_vec3(LCR_PHYSICS_UNIT / 2,0,0),
LCR_PHYSICS_UNIT / 2 + LCR_PHYSICS_UNIT / 4) :
TPE_envAABox(point,TPE_vec3(0,0,0),
TPE_vec3(LCR_PHYSICS_UNIT / 2,LCR_PHYSICS_UNIT / 4,
LCR_PHYSICS_UNIT / 2));
if (point.y < -1 * LCR_PHYSICS_UNIT / 4) // for some reason happens somet.
point.y = -1 * LCR_PHYSICS_UNIT / 4;
break;
}
case LCR_BLOCK_BUMP:
point = TPE_envCone(point,TPE_vec3(0,-1 * LCR_PHYSICS_UNIT / 4 ,0),
TPE_vec3(0,LCR_PHYSICS_UNIT / 6,0),(5 * LCR_PHYSICS_UNIT) / 12);
break;
case LCR_BLOCK_CORNER:
case LCR_BLOCK_CORNER_12:
{
TPE_Unit sides[6];
sides[0] = -1 * LCR_PHYSICS_UNIT / 2;
sides[1] = LCR_PHYSICS_UNIT / 2;
sides[2] = -1 * LCR_PHYSICS_UNIT / 2;
sides[3] = -1 * LCR_PHYSICS_UNIT / 2;
sides[4] = block[0] == LCR_BLOCK_CORNER ? LCR_PHYSICS_UNIT / 2 : 0;
sides[5] = LCR_PHYSICS_UNIT / 2;
point = TPE_envAATriPrism(point,TPE_vec3(0,0,0),sides,
LCR_PHYSICS_UNIT / 2,1);
break;
}
default:
point = TPE_vec3(0,0,LCR_MAP_SIZE_BLOCKS * LCR_PHYSICS_UNIT);
break;
}
point = TPE_vec3Plus(point,
TPE_vec3(LCR_PHYSICS_UNIT / 2,LCR_PHYSICS_UNIT / 4,LCR_PHYSICS_UNIT / 2));
transform = LCR_mapBlockOppositeTransform(transform);
LCR_TRANSFORM_COORDS(transform,point.x,point.y,point.z,LCR_PHYSICS_UNIT,
(LCR_PHYSICS_UNIT / 2))
point = TPE_vec3Plus(point,blockOffset); // shift back
return point;
}
/**
For tinyphysicsengine, function that defines the shape of physics world,
returns closest point to any given point in space.
*/
TPE_Vec3 _LCR_racingEnvironmentFunction(TPE_Vec3 point, TPE_Unit maxDist)
{
// start with the map outside walls:
TPE_ENV_START(TPE_envAABoxInside(point,TPE_vec3(0,0,0),TPE_vec3(
LCR_PHYSICS_UNIT * LCR_MAP_SIZE_BLOCKS,
(LCR_PHYSICS_UNIT * LCR_MAP_SIZE_BLOCKS) / 2,
LCR_PHYSICS_UNIT * LCR_MAP_SIZE_BLOCKS)),point)
// without this check we might try to get block outside the map
if (_pBest.x == point.x && _pBest.y == point.y && _pBest.z == point.z)
return _pBest;
if (maxDist <= LCR_PHYSICS_UNIT / 4) // considering half of square height
{
/* Here we only check the 8 closest blocks => relatively fast. */
TPE_Vec3 pointShifted = TPE_vec3Plus(point,TPE_vec3(
(LCR_MAP_SIZE_BLOCKS / 2) * LCR_PHYSICS_UNIT,
(LCR_MAP_SIZE_BLOCKS / 4) * LCR_PHYSICS_UNIT,
(LCR_MAP_SIZE_BLOCKS / 2) * LCR_PHYSICS_UNIT));
uint8_t coords[6]; // x_low, x_high, y_low, y_high, z_low, z_high
coords[0] = (pointShifted.x / LCR_PHYSICS_UNIT);
coords[1] = (pointShifted.x % LCR_PHYSICS_UNIT < LCR_PHYSICS_UNIT / 2);
coords[2] = (pointShifted.y / (LCR_PHYSICS_UNIT / 2));
coords[3] =
(pointShifted.y % (LCR_PHYSICS_UNIT / 2) < LCR_PHYSICS_UNIT / 4);
coords[4] = (pointShifted.z / LCR_PHYSICS_UNIT);
coords[5] = (pointShifted.z % LCR_PHYSICS_UNIT < LCR_PHYSICS_UNIT / 2);
for (int i = 0; i < 6; i += 2)
if (coords[i + 1])
{
coords[i + 1] = coords[i];
coords[i] = coords[i] > 0 ? coords[i] - 1 : 0;
}
else
coords[i + 1] = coords[i] < 63 ? coords[i] + 1 : 63;
int start = 0, end = LCR_currentMap.blockCount - 1;
for (uint8_t i = 0; i < 8; ++i)
{
/* Black magic: here we make it so that we the lowest coord numbers
(0,0,0), then the highest (1,1,1), then second lowest (1,0,0), then
second highest (0,1,1) etc. This way we are narrowing the range (start,
end) for the binary search. */
int blockNum = LCR_mapGetBlockAtFast(
coords[0] + ((i ^ (i >> 1)) & 0x01),
coords[2] + ((i ^ (i >> 2)) & 0x01),
coords[4] + (i & 0x01),start,end);
if (blockNum >= 0) // is there a block at the coords?
{
TPE_ENV_NEXT(_LCR_racingBlockEnvFunc(point, // check it
LCR_currentMap.blocks + blockNum * LCR_BLOCK_SIZE),point)
// narrow the search range:
if (i % 2 == 0 && blockNum > start)
start = blockNum;
if (i % 2 && blockNum < end)
end = blockNum;
}
}
}
else
{
LCR_LOG1("collision checking all blocks (shouldn't happen often!)");
const uint8_t *block = LCR_currentMap.blocks;
// Full check of all map blocks, slow, shouldn't happen often!
for (int j = 0; j < LCR_currentMap.blockCount; ++j)
{
TPE_ENV_NEXT(_LCR_racingBlockEnvFunc(point,block),point)
block += LCR_BLOCK_SIZE;
}
}
TPE_ENV_END
}
LCR_GameUnit LCR_racingGetCarSpeedUnsigned(void)
{
return LCR_racing.carSpeed >= 0 ? LCR_racing.carSpeed :
(-1 * LCR_racing.carSpeed);
}
LCR_GameUnit LCR_racingGetCarSpeedSigned(void)
{
return LCR_racing.carSpeed;
}
uint8_t _LCR_racingCollisionHandler(uint16_t b1, uint16_t j1, uint16_t b2,
uint16_t j2, TPE_Vec3 p)
{
// check which wheels are touching the ground.
if (j1 < 4) // wheel joint?
LCR_racing.wheelCollisions |= 0x01 << j1;
return 1;
}
LCR_GameUnit _LCR_racingSmoothRot(LCR_GameUnit angleNew, LCR_GameUnit angleOld)
{
/* We'll smooth small rotations by averaging the last two angles; bigger
rotations won't be smoothed -- firstly this removes lag for fast rotations
and also deals with the issue of averaging e.g. 1 and 359 degrees. */
LCR_GameUnit diff = angleNew - angleOld;
if (diff > LCR_GAME_UNIT / 8 || diff < -1 * LCR_GAME_UNIT / 8)
return angleNew;
return angleOld + diff / 2;
}
TPE_Vec3 _LCR_racingGetWheelCenterPoint(void)
{
return _LCR_TPE_vec3DividePlain(
TPE_vec3Plus(
TPE_vec3Plus(
LCR_racing.carBody.joints[0].position,
LCR_racing.carBody.joints[1].position),
TPE_vec3Plus(
LCR_racing.carBody.joints[2].position,
LCR_racing.carBody.joints[3].position)),4);
}
void _LCR_racingUpdateCarPosRot(void)
{
TPE_Vec3 tmpVec = LCR_racing.carPositions[0];
LCR_racing.carPositions[0] = _LCR_TPE_vec3DividePlain(
TPE_vec3TimesPlain(_LCR_racingGetWheelCenterPoint(),LCR_GAME_UNIT),
LCR_PHYSICS_UNIT);
LCR_racing.carPositions[0] = // smooth the position
TPE_vec3KeepWithinBox(LCR_racing.carPositions[1],LCR_racing.carPositions[0],
TPE_vec3(
LCR_PHYSICS_UNIT / 64, // TODO: constant
LCR_PHYSICS_UNIT / 64,
LCR_PHYSICS_UNIT / 64));
LCR_racing.carPositions[1] = tmpVec;
tmpVec = _LCR_TPE_vec3DividePlain(TPE_vec3TimesPlain(TPE_bodyGetRotation(
&(LCR_racing.carBody),0,2,1),LCR_GAME_UNIT),TPE_F);
LCR_racing.carRotations[1] = LCR_racing.carRotations[0];
LCR_racing.carRotations[0] = tmpVec;
}
/**
Initializes new run.
*/
void LCR_racingRestart(void)
{
LCR_LOG0("restarting race");
LCR_racing.tick = 0;
LCR_racing.fanForce = 0;
TPE_bodyActivate(&(LCR_racing.carBody));
LCR_racing.wheelCollisions = 0;
LCR_racing.wheelAngle = 0;
LCR_racing.wheelSteer = 0;
LCR_racing.carSpeed = 0;
LCR_racing.carDrifting = 0;
// make the car body:
TPE_makeCenterRectFull(LCR_racing.carJoints,
LCR_racing.carConnections,
LCR_PHYSICS_UNIT / 2,
(LCR_PHYSICS_UNIT * 3) / 4,
LCR_PHYSICS_UNIT / 8);
LCR_racing.carJoints[4].position.y += LCR_PHYSICS_UNIT / 6;
LCR_racing.carJoints[4].sizeDivided *= 3;
LCR_racing.carJoints[4].sizeDivided /= 2;
TPE_bodyInit(&(LCR_racing.carBody),LCR_racing.carJoints,LCR_CAR_JOINTS,
LCR_racing.carConnections,LCR_CAR_CONNECTIONS,TPE_F);
LCR_racing.carBody.friction = LCR_CAR_FORWARD_FRICTION;
LCR_racing.carBody.elasticity = LCR_CAR_ELASTICITY;
LCR_racing.carBody.flags |= TPE_BODY_FLAG_ALWAYS_ACTIVE;
/* We disable bounding sphere checks because that would lead to calling env.
function with large min. distance which would lead to slow iteration over
all map blocks. */
LCR_racing.carBody.flags |= TPE_BODY_FLAG_NO_BSPHERE;
TPE_bodyMoveTo(&(LCR_racing.carBody),TPE_vec3(
(((TPE_Unit) LCR_currentMap.startPos[0]) - LCR_MAP_SIZE_BLOCKS / 2)
* LCR_PHYSICS_UNIT + LCR_PHYSICS_UNIT / 2,
(((TPE_Unit) LCR_currentMap.startPos[1]) - LCR_MAP_SIZE_BLOCKS / 2)
* LCR_PHYSICS_UNIT / 2 + LCR_PHYSICS_UNIT / 4,
(((TPE_Unit) LCR_currentMap.startPos[2]) - LCR_MAP_SIZE_BLOCKS / 2)
* LCR_PHYSICS_UNIT + LCR_PHYSICS_UNIT / 2));
if (LCR_currentMap.startPos[3])
{
uint8_t trans = LCR_currentMap.startPos[3];
if (trans & LCR_BLOCK_TRANSFORM_FLIP_V)
TPE_bodyRotateByAxis(&(LCR_racing.carBody),
TPE_vec3(TPE_FRACTIONS_PER_UNIT / 2,0,0));
trans &=
LCR_BLOCK_TRANSFORM_ROT_90 |
LCR_BLOCK_TRANSFORM_ROT_180 |
LCR_BLOCK_TRANSFORM_ROT_270;
TPE_bodyRotateByAxis(&(LCR_racing.carBody),
TPE_vec3(0,(trans == LCR_BLOCK_TRANSFORM_ROT_90) ?
3 * TPE_F / 4 : (trans == LCR_BLOCK_TRANSFORM_ROT_180) ?
TPE_F / 2 : (TPE_F / 4),0));
}
for (int i = 0; i < LCR_CAR_JOINTS; ++i)
LCR_racing.carOKPositions[i] = TPE_vec3(0,0,0);
LCR_racing.carNotOKCount = 0;
LCR_racing.carPositions[0] = TPE_vec3(0,0,0);
LCR_racing.carPositions[1] = LCR_racing.carPositions[0];
LCR_racing.carRotations[0] = TPE_vec3(0,0,0);
LCR_racing.carRotations[1] = LCR_racing.carRotations[0];
_LCR_racingUpdateCarPosRot();
LCR_racing.carPositions[1] = LCR_racing.carPositions[0];
LCR_racing.carRotations[1] = LCR_racing.carRotations[0];
}
/**
Initializes the racing module, only call once.
*/
void LCR_racingInit(void)
{
LCR_LOG0("initializing racing engine");
TPE_worldInit(&(LCR_racing.physicsWorld),
&(LCR_racing.carBody),1,_LCR_racingEnvironmentFunction);
LCR_racing.physicsWorld.collisionCallback = _LCR_racingCollisionHandler;
}
/**
Gets current car transformation intended for rendering, i.e. potentially with
smoothing and interpolation applied to the underlying internal state in the
physics engine.
*/
void LCR_racingGetCarTransform(LCR_GameUnit position[3],
LCR_GameUnit rotation[3], LCR_GameUnit interpolationParam)
{
LCR_LOG2("getting car transform");
TPE_Vec3 v;
#if LCR_SETTING_SMOOTH_ANIMATIONS
v = TPE_vec3Plus(LCR_racing.carPositions[1], // LERP previous and current pos
_LCR_TPE_vec3DividePlain(
TPE_vec3TimesPlain(TPE_vec3Minus(
LCR_racing.carPositions[0],LCR_racing.carPositions[1]),
interpolationParam),LCR_GAME_UNIT));
position[0] = v.x;
position[1] = v.y;
position[2] = v.z;
rotation[0] = _LCR_racingSmoothRot(LCR_racing.carRotations[0].x,
LCR_racing.carRotations[1].x);
rotation[1] = _LCR_racingSmoothRot(LCR_racing.carRotations[0].y,
LCR_racing.carRotations[1].y);
rotation[2] = _LCR_racingSmoothRot(LCR_racing.carRotations[0].z,
LCR_racing.carRotations[1].z);
#else
position[0] = LCR_racing.carPositions[0].x;
position[1] = LCR_racing.carPositions[0].y;
position[2] = LCR_racing.carPositions[0].z;
rotation[0] = LCR_racing.carRotations[0].x;
rotation[1] = LCR_racing.carRotations[0].y;
rotation[2] = LCR_racing.carRotations[0].z;
#endif
}
void _LCR_drawPhysicsDebugPixel(uint16_t x, uint16_t y, uint8_t color)
{
if (x > 1 && x < LCR_EFFECTIVE_RESOLUTION_X - 2 &&
y > 1 && y < LCR_EFFECTIVE_RESOLUTION_Y - 2)
{
uint16_t c = 0x8101 | (0x8f1f << (2 * color));
for (int j = -1; j <= 2; ++j)
for (int i = -1; i <= 2; ++i)
LCR_drawPixelXYUnsafe(x + i,y + j,c);
}
}
int LCR_racingCarWheelTouchesGround(int wheel)
{
return ((LCR_racing.wheelCollisions & (LCR_racing.wheelCollisions >> 4))
>> wheel) & 0x01;
}
LCR_GameUnit LCR_racingGetWheelRotation(void)
{
return LCR_racing.wheelAngle;
}
LCR_GameUnit LCR_racingGetWheelSteer(void)
{
return LCR_racing.wheelSteer;
}
TPE_Unit _LCR_applyMaterialFactor(TPE_Unit value, uint8_t mat)
{
switch (mat)
{
case LCR_BLOCK_MATERIAL_GRASS:
value *= LCR_CAR_GRASS_FACTOR;
break;
case LCR_BLOCK_MATERIAL_DIRT:
value *= LCR_CAR_DIRT_FACTOR;
break;
case LCR_BLOCK_MATERIAL_ICE:
value *= LCR_CAR_ICE_FACTOR;
break;
default: value *= 8; break;
}
return value / 8;
}
void _LCR_racingWheelAccelerate(unsigned int wheel, TPE_Vec3 dir,
uint8_t material, uint8_t accelerator)
{
TPE_Unit acc =
_LCR_applyMaterialFactor(LCR_CAR_ACCELERATION,material);
acc = acc / (1 + (LCR_racingGetCarSpeedUnsigned() / LCR_CAR_AIR_FRICTION));
if (accelerator)
acc *= 2; // TODO: constant?
LCR_racing.carBody.joints[wheel].velocity[0] += (dir.x * acc) / TPE_F;
LCR_racing.carBody.joints[wheel].velocity[1] += (dir.y * acc) / TPE_F;
LCR_racing.carBody.joints[wheel].velocity[2] += (dir.z * acc) / TPE_F;
}
int _LCR_racingCarShapeOK(void)
{
int r = 1;
for (int i = 0; i < LCR_racing.carBody.jointCount; ++i)
r &= TPE_connectionTension(TPE_dist(
LCR_racing.carBody.joints[
LCR_racing.carBody.connections[i].joint1].position,
LCR_racing.carBody.joints[
LCR_racing.carBody.connections[i].joint2].position),
LCR_racing.carBody.connections[i].length) < TPE_F / 16; // TODO: const
return r;
}
/**
Updates the racing physics world, call every LCR_RACING_TICK_MS milliseconds.
Returns a set of events (logically ORed) that occured during this step.
*/
uint32_t LCR_racingStep(unsigned int input)
{
LCR_LOG2("racing step start");
uint32_t result = 0;
TPE_Vec3 carForw, carRight, carUp, carVel;
uint8_t groundMat = LCR_BLOCK_MATERIAL_CONCRETE; // material under wheels
uint8_t onAccel = 0; // standing on accelerator?
int groundBlockIndex = -1;
carForw = TPE_vec3Normalized(TPE_vec3Plus(
TPE_vec3Minus(LCR_racing.carBody.joints[0].position,
LCR_racing.carBody.joints[2].position),
TPE_vec3Minus(LCR_racing.carBody.joints[1].position,
LCR_racing.carBody.joints[3].position)));
carRight = TPE_vec3Normalized(TPE_vec3Plus(
TPE_vec3Minus(LCR_racing.carBody.joints[0].position,
LCR_racing.carBody.joints[1].position),
TPE_vec3Minus(LCR_racing.carBody.joints[2].position,
LCR_racing.carBody.joints[3].position)));
carUp = TPE_vec3Cross(carForw,carRight);
carVel = TPE_vec3(
LCR_racing.carBody.joints[4].velocity[0],
LCR_racing.carBody.joints[4].velocity[1],
LCR_racing.carBody.joints[4].velocity[2]);
if ((LCR_racing.wheelCollisions & 0x0f) != 0x0f) // EXPERIMENTAL: don't apply gravity with all wheels on ground
TPE_bodyApplyGravity(&(LCR_racing.carBody),LCR_GRAVITY);
if (LCR_racing.wheelCollisions) // at least one wheel on ground?
{
TPE_Unit upDot = TPE_vec3Dot(carUp,TPE_vec3(0,TPE_F,0));
if (upDot > TPE_F / 8 || upDot < -1 * TPE_F / 8) // TODO: consts
{
uint8_t
gx = (LCR_racing.carPositions[0].x + (LCR_MAP_SIZE_BLOCKS / 2) *
LCR_GAME_UNIT) / LCR_GAME_UNIT,
gy = (LCR_racing.carPositions[0].y + (LCR_MAP_SIZE_BLOCKS / 2) *
(LCR_GAME_UNIT / 2)) / (LCR_GAME_UNIT / 2),
gz = (LCR_racing.carPositions[0].z + (LCR_MAP_SIZE_BLOCKS / 2) *
LCR_GAME_UNIT) / LCR_GAME_UNIT;
TPE_Unit yMod = (LCR_racing.carPositions[0].y + LCR_MAP_SIZE_BLOCKS *
LCR_GAME_UNIT / 2) % (LCR_GAME_UNIT / 2);
if (upDot > 0 && yMod < LCR_GAME_UNIT / 2) // TODO: const
groundBlockIndex = LCR_mapGetBlockAt(gx,gy - 1,gz);
else if (upDot < 0 && yMod > LCR_GAME_UNIT / 2)
groundBlockIndex = LCR_mapGetBlockAt(gx,gy + 1,gz);
if (groundBlockIndex == -1)
groundBlockIndex = LCR_mapGetBlockAt(gx,gy,gz);
}
if (groundBlockIndex != -1)
{
uint8_t b = LCR_currentMap.blocks[groundBlockIndex * LCR_BLOCK_SIZE];
onAccel = LCR_mapBlockIsAccelerator(b);
if (LCR_mapBlockIsFan(b))
LCR_racing.fanForce = LCR_GRAVITY * LCR_FAN_FORCE;
groundMat = LCR_mapBlockGetMaterial(
LCR_currentMap.blocks + groundBlockIndex * LCR_BLOCK_SIZE);
}
}
LCR_racing.carBody.friction =
_LCR_applyMaterialFactor(LCR_CAR_FORWARD_FRICTION,groundMat);
if (onAccel)
input |= LCR_RACING_INPUT_FORW; // accelerator enforces this
if(!(input & (LCR_RACING_INPUT_FORW | LCR_RACING_INPUT_BACK)))
LCR_racing.carBody.friction *= LCR_CAR_STAND_FRICTION_MULTIPLIER;
else if (
((input & LCR_RACING_INPUT_FORW) && (LCR_racing.carSpeed < 0)) ||
((input & LCR_RACING_INPUT_BACK) && (LCR_racing.carSpeed > 0)))
LCR_racing.carBody.friction *= 2 * LCR_CAR_STAND_FRICTION_MULTIPLIER;
if (input)
{
unsigned char steering = 0;
if ((input & LCR_RACING_INPUT_BACK) &&
(LCR_racing.wheelCollisions & 0x0f) == 0x00) // in air?
{
LCR_LOG2("air brake");
for (int i = 0; i < LCR_CAR_JOINTS - 1; ++i)
for (int j = 0; j < 3; ++j)
LCR_racing.carBody.joints[i].velocity[j] =
LCR_racing.carBody.joints[LCR_CAR_JOINTS - 1].velocity[j];
}
// TODO: magic constants
if (input & (LCR_RACING_INPUT_FORW | LCR_RACING_INPUT_BACK))
{
LCR_GameUnit rotateBy =
(LCR_racing.wheelCollisions & 0x0f) ? // on ground slow down wheel rot.
(LCR_racingGetCarSpeedUnsigned() / 8) : LCR_GAME_UNIT / 32;
if (!(input & LCR_RACING_INPUT_BACK))
rotateBy *= -1;
LCR_racing.wheelAngle =
(LCR_racing.wheelAngle + rotateBy) % LCR_GAME_UNIT;
if (LCR_racing.wheelAngle < 0)
LCR_racing.wheelAngle += LCR_GAME_UNIT;
}
if (input & LCR_RACING_INPUT_RIGHT)
{
steering = 2;
LCR_racing.wheelSteer = TPE_min(
LCR_racing.wheelSteer + LCR_CAR_STEER_SPEED,
LCR_CAR_STEER_MAX);
}
else if (input & LCR_RACING_INPUT_LEFT)
{
steering = 1;
LCR_racing.wheelSteer = TPE_max(
LCR_racing.wheelSteer - LCR_CAR_STEER_SPEED,
-1 * LCR_CAR_STEER_MAX);
}
if ((LCR_racing.wheelCollisions & 0x0c)) // back wheel on ground?
{
if (input & LCR_RACING_INPUT_FORW)
{
_LCR_racingWheelAccelerate(0,carForw,groundMat,onAccel);
_LCR_racingWheelAccelerate(1,carForw,groundMat,onAccel);
}
else if (input & LCR_RACING_INPUT_BACK)
{
_LCR_racingWheelAccelerate(0,TPE_vec3TimesPlain(carForw,-1),groundMat,onAccel);
_LCR_racingWheelAccelerate(1,TPE_vec3TimesPlain(carForw,-1),groundMat,onAccel);
}
}
TPE_Unit driftFriction = 0; // average wheel friction (absolute value)
for (int i = 0; i < 4; ++i)
if (LCR_racing.wheelCollisions & (0x01 << i)) // wheel on ground?
{
TPE_Vec3 jv = TPE_vec3( // joint velocity
LCR_racing.carBody.joints[i].velocity[0],
LCR_racing.carBody.joints[i].velocity[1],
LCR_racing.carBody.joints[i].velocity[2]);
TPE_Vec3 ja = carRight; // wheel axis of rotation
if (i >= 2 && steering)
{
// for front wheels with turning we tilt the wheel axis 45 degrees
TPE_Unit steer =
(LCR_racing.wheelSteer * TPE_F) / LCR_GAME_UNIT;
ja = TPE_vec3Normalized(
TPE_vec3Plus(TPE_vec3Times(carForw,steer),carRight));
}
/* friction is in the direction if the axis and its magnitude is
determined by the dot product (angle) of the axis and velocity */
TPE_Vec3 fric = TPE_vec3Times(ja,(TPE_vec3Dot(ja,jv) *
_LCR_applyMaterialFactor(
LCR_racing.carDrifting ?
(LCR_CAR_STEER_FRICTION * LCR_CAR_DRIFT_FACTOR) / 8 :
LCR_CAR_STEER_FRICTION,groundMat)) / TPE_F);
driftFriction += TPE_vec3Len(fric);
jv = TPE_vec3Minus(jv,fric); // subtract the friction
LCR_racing.carBody.joints[i].velocity[0] = jv.x;
LCR_racing.carBody.joints[i].velocity[1] = jv.y;
LCR_racing.carBody.joints[i].velocity[2] = jv.z;
}
driftFriction /= 4;
if ((!LCR_racing.carDrifting) &&
driftFriction > LCR_CAR_DRIFT_THRESHOLD_1)
{
LCR_LOG1("drift start");
LCR_racing.carDrifting = 1;
}
else if (LCR_racing.carDrifting &&
driftFriction < LCR_CAR_DRIFT_THRESHOLD_0)
{
LCR_LOG1("drift end");
LCR_racing.carDrifting = 0;
}
/* The following fixes "sticking to a wall" issue by adding a small spin
to the car when trying to steer at very small velocity. */
if (steering &&
(input & (LCR_RACING_INPUT_FORW | LCR_RACING_INPUT_BACK)) &&
(LCR_racing.wheelCollisions & 0x0f) &&
LCR_racingGetCarSpeedUnsigned() < (LCR_GAME_UNIT / 25))
{
LCR_LOG2("spinning car a bit");
TPE_bodySpin(&LCR_racing.carBody,TPE_vec3(0,
steering == ((input & LCR_RACING_INPUT_LEFT) != 0) ?
TPE_F / 32 : -1 * TPE_F / 32,0));
}
}
if ((!(input & LCR_RACING_INPUT_LEFT)) &&
(!(input & LCR_RACING_INPUT_RIGHT)))
LCR_racing.wheelSteer /= 2;
LCR_racing.wheelCollisions <<= 4;
if (LCR_racing.fanForce)
{
TPE_bodyAccelerate(&(LCR_racing.carBody),TPE_vec3(0,LCR_racing.fanForce,0));
LCR_racing.fanForce -= LCR_GRAVITY / LCR_FAN_FORCE_DECREASE;
if (LCR_racing.fanForce < 0)
LCR_racing.fanForce = 0;
}
LCR_LOG2("gonna step physics engine");
TPE_worldStep(&(LCR_racing.physicsWorld));
LCR_LOG2("stepping physics engine done");
LCR_racing.carSpeed = (TPE_vec3Len(carVel) * LCR_GAME_UNIT)
/ LCR_PHYSICS_UNIT;
if (TPE_vec3Dot(carVel,carForw) < 0)
LCR_racing.carSpeed *= -1;
_LCR_racingUpdateCarPosRot();
TPE_Unit angle = TPE_vec3Dot(carUp,TPE_vec3Normalized(TPE_vec3Minus(
LCR_racing.carBody.joints[4].position,
LCR_racing.carBody.joints[0].position)));
if (angle < TPE_F / 64) // TODO: magic constant
{
LCR_LOG2("roof squeezed, applying anti force")
TPE_Vec3 tmpVec = TPE_vec3Times(carUp,LCR_PHYSICS_UNIT / 16); // TODO: 16 magic con.
angle = TPE_F - 4 * angle; // 4 comes from above TPE_F / 4
tmpVec = TPE_vec3Times(tmpVec,angle);
if (angle <= 0)
{
LCR_LOG1("roof flipped over, fixing")
LCR_racing.carBody.joints[4].position = _LCR_racingGetWheelCenterPoint();
angle = 0;
}
// accelerate roof and wheels away from each other
for (int i = 0; i < LCR_CAR_JOINTS; ++i)
{
LCR_racing.carBody.joints[i].velocity[0] += (i == 4 ? 1 : -1) * tmpVec.x;
LCR_racing.carBody.joints[i].velocity[1] += (i == 4 ? 1 : -1) * tmpVec.y;
LCR_racing.carBody.joints[i].velocity[2] += (i == 4 ? 1 : -1) * tmpVec.z;
}
}
// now make a special test for a "pinch" front collision
TPE_Vec3 frontWheelMiddle = TPE_vec3Plus(
LCR_racing.carBody.joints[0].position,
LCR_racing.carBody.joints[1].position);
frontWheelMiddle.x /= 2;
frontWheelMiddle.y /= 2;
frontWheelMiddle.z /= 2;
frontWheelMiddle = TPE_vec3Minus(frontWheelMiddle,
_LCR_racingEnvironmentFunction(frontWheelMiddle,LCR_PHYSICS_UNIT / 4));
uint8_t frontCollision =
carForw.y < TPE_FRACTIONS_PER_UNIT / 4 && // only when car is horizontal
carForw.y > -1 * TPE_FRACTIONS_PER_UNIT / 4 &&
frontWheelMiddle.x == 0 && frontWheelMiddle.y == 0 &&
frontWheelMiddle.z == 0;
if (frontCollision)
{
// stop the car immediately
LCR_LOG1("car front pierced");
LCR_racing.carNotOKCount +=
(LCR_racing.carNotOKCount < 20 ? 15 : 0); // TODO: consts
}
if ((LCR_racing.carBody.flags & TPE_BODY_FLAG_UNRESOLVED) || frontCollision ||
!_LCR_racingCarShapeOK())
{
// car not OK
if (LCR_racing.carNotOKCount > 10) // TODO: constant
{
LCR_LOG1("car not OK (short), fixing");
for (int i = 0; i < LCR_CAR_JOINTS; ++i)
{
if (LCR_racing.carNotOKCount < 20) // TODO: const
{
// for a while try to smoothly iterate towards previous OK position
LCR_racing.carBody.joints[i].position =
TPE_vec3Plus(LCR_racing.carBody.joints[i].position,
LCR_racing.carOKPositions[i]);
LCR_racing.carBody.joints[i].position.x /= 2;
LCR_racing.carBody.joints[i].position.y /= 2;
LCR_racing.carBody.joints[i].position.z /= 2;
for (int j = 0; j < 3; ++j) // lower speed a bit
LCR_racing.carBody.joints[i].velocity[j] =
(7 * ((int) LCR_racing.carBody.joints[i].velocity[j])) / 8;
}
else // hard set the pos (iteration may be infinite due to sim.)
{
LCR_LOG1("car not OK (long), teleporting");
LCR_racing.carBody.joints[i].position = LCR_racing.carOKPositions[i];
}
}
}
LCR_racing.carNotOKCount += LCR_racing.carNotOKCount < 255 ? 1 : 0;
}
else
{
// car OK
LCR_racing.carNotOKCount = 0;
for (int i = 0; i < LCR_CAR_JOINTS; ++i)
LCR_racing.carOKPositions[i] = LCR_racing.carBody.joints[i].position;
}
LCR_racing.tick++;
LCR_LOG2("racing step end");
return result;
}
void LCR_physicsDebugDraw(LCR_GameUnit camPos[3], LCR_GameUnit camRot[2],
LCR_GameUnit camFov)
{
#if LCR_SETTING_DEBUG_PHYSICS_DRAW
LCR_LOG2("drawing physics debug overlay");
TPE_Vec3 cPos, cRot, cView;
cPos.x = (camPos[0] * LCR_PHYSICS_UNIT) / LCR_GAME_UNIT;
cPos.y = (camPos[1] * LCR_PHYSICS_UNIT) / LCR_GAME_UNIT;
cPos.z = (camPos[2] * LCR_PHYSICS_UNIT) / LCR_GAME_UNIT;
cRot.x = (camRot[0] * TPE_F) / LCR_GAME_UNIT;
cRot.y = (camRot[1] * TPE_F) / LCR_GAME_UNIT;
cRot.z = 0;
cView.x = LCR_EFFECTIVE_RESOLUTION_X;
cView.y = LCR_EFFECTIVE_RESOLUTION_Y;
cView.z = (camFov * TPE_F) / LCR_GAME_UNIT;
TPE_worldDebugDraw(&(LCR_racing.physicsWorld),_LCR_drawPhysicsDebugPixel,
cPos,cRot,cView,16,LCR_PHYSICS_UNIT / 4,LCR_racing.tick * 4);
#endif
}
#endif // guard
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