/**
  WIP raycasting demo for Pokitto.

  Don't forget to compile with -O3!

  author: Miloslav "drummyfish" Ciz
  license: CC0 1.0
*/

// redefine player's height
#define CAMERA_COLL_HEIGHT_BELOW ((3 * UNITS_PER_SQUARE) / 2)

#include "general.hpp"

#define LEVEL_X_RES 29
#define LEVEL_Y_RES 21

Player player;

#define SPRITE_MAX_DISTANCE 5 * UNITS_PER_SQUARE

#define JUMP_SPEED 500

char floorColor = 0;
Vector2D selectedSquare; ///< Coords of tile selected for editing.

/**
  Represents one terrain change against the implicit terrain.
*/
class Change
{
public:
  Vector2D mCoords;
  Unit mHeight;
  uint8_t mColor;
};

#define MAX_CHANGES 32

Change changes[MAX_CHANGES];

bool editReleased = false;
bool editing = false;
uint16_t changeIndex = 0;

#define HEIGHT_PROFILE_LENGTH 256
const int8_t heightProfile[] = {
9,9,9,10,10,10,11,11,12,13,13,14,14,14,15,15,15,16,16,16,16,16,15,15,15,14,14,
13,13,12,11,10,10,9,9,9,8,8,8,8,8,8,7,7,7,6,5,4,4,3,3,3,3,3,3,4,5,7,8,10,11,12,
12,13,13,13,14,16,19,20,21,21,22,22,22,23,23,23,23,22,22,21,20,19,18,18,17,17,
17,17,16,16,16,16,16,16,16,15,15,15,14,14,13,12,11,10,8,7,6,5,5,5,4,4,4,4,4,5,
5,5,6,6,7,7,7,8,8,8,8,8,8,8,7,7,7,7,6,6,5,4,4,3,2,2,2,1,1,1,1,2,3,5,6,7,9,13,
13,13,18,18,22,22,22,22,22,22,21,21,20,20,19,16,16,16,14,14,14,15,15,15,15,15,
16,17,17,18,18,18,16,16,16,16,15,15,15,14,14,13,12,8,7,7,7,8,9,11,12,12,13,13,
13,12,11,10,10,10,10,11,11,12,13,13,12,12,11,11,10,10,9,9,9,9,9,9,10,10,11,12,
13,13,14,14,14,14,14,13,13,12,11,11,11,11,10,10,10,10};

const unsigned char imageBackground[] =
{  55, 44 // width, height
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xff,0xff
  ,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xff,0xd2,0xd2,0xd2,0xd2,0xd2,0x69
  ,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xff,0xff,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2
  ,0x69,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xff,0xff,0xff,0xbc,0xbc,0xdb
  ,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b,0x3b,0xdb,0xdb
  ,0xdb,0xdb,0xff,0xff,0xff,0xff,0xbc,0xbc,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2
  ,0xd2,0xd2,0x3b,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xff,0xff,0xff,0xff
  ,0xff,0xbc,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0x3b,0x3b,0x3b
  ,0xdb,0xdb,0xdb,0xdb,0xff,0xff,0xff,0xff,0xff,0xbc,0xdb,0xdb,0xd2,0xd2
  ,0xd2,0xd2,0xd2,0x69,0x3b,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xff,0xff
  ,0xff,0xff,0xff,0xbc,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0x3b
  ,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xff,0xff,0xff,0xbc,0xbc,0xdb,0xdb
  ,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xff,0xff,0xbc,0xbc,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2
  ,0x3b,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xff,0xff,0xff,0xbc,0xdb
  ,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0x3b,0x3b,0xdb,0xdb
  ,0xdb,0xdb,0xff,0xff,0xff,0xff,0xff,0xbc,0xdb,0xdb,0xbc,0xd2,0xd2,0xd2
  ,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xff,0xff,0xff,0xbc
  ,0xff,0xbc,0xdb,0xdb,0xff,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xff,0xff,0xbc,0xff,0xff,0xbc,0xbc,0xff,0xd2
  ,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xff
  ,0xbc,0xbc,0xff,0xff,0xbc,0xff,0xff,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2
  ,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xbc,0xdb,0xff,0xff,0xff,0xff
  ,0xbc,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xff,0xff,0xbc,0xbc,0xd2,0xd2,0xd2,0xd2,0xd2
  ,0xd2,0xd2,0x69,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xff
  ,0xbc,0xbc,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xff,0xbc,0xd2,0xd2,0xd2,0xd2
  ,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xff,0xbc,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xff,0xbc,0xd2
  ,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xbc,0xbc,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2
  ,0x69,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xbc
  ,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0xbc,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2
  ,0xd2,0xd2,0x3b,0x3b,0xbc,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0xbc,0xbc
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2
  ,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0xff,0xbc,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0x3b
  ,0xff,0xbc,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2
  ,0xd2,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0x3b,0xff,0xff,0xbc,0xdb,0xbc,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b
  ,0x3b,0x3b,0xff,0xff,0xbc,0xdb,0xff,0xbc,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0x3b,0x3b,0xff,0xbc,0xbc,0xdb
  ,0xff,0xbc,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2
  ,0x3b,0x3b,0x3b,0x3b,0xff,0xbc,0xbc,0xdb,0xff,0xbc,0xbc,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b,0x3b,0xff,0xbc
  ,0xbc,0xbc,0xff,0xff,0xbc,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2
  ,0xd2,0xd2,0x3b,0x3b,0x3b,0x3b,0xbc,0xbc,0xff,0xbc,0xff,0xff,0xbc,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b,0x3b
  ,0xbc,0xdb,0xff,0xff,0xff,0xff,0xbc,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2
  ,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0x3b,0x3b,0xbc,0xdb,0xff,0xff,0xff,0xbc
  ,0xbc,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b
  ,0x3b,0x3b,0xbc,0xdb,0xff,0xff,0xdb,0xbc,0xbc,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b,0xbc,0xdb,0xff,0xbc
  ,0xdb,0xbc,0xbc,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2
  ,0xd2,0x69,0x3b,0x3b,0xdb,0xdb,0xff,0xdb,0xdb,0xdb,0xbc,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0x3b,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xbc,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2
  ,0xd2,0xd2,0xd2,0x69,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0x3b
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2
  ,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x69,0x3b
  ,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2
  ,0x3b,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xbc,0xd2,0xd2,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b,0x3b,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xbc,0xbc,0xd2,0xd2,0xd2
  ,0xd2,0xd2,0x3b,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xff,0xff,0xbc,0xbc,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b,0x3b
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xff,0xff,0xff,0xbc
  ,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xff,0xff,0xff,0xbc,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b
  ,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xff
  ,0xff,0xff,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xff,0xff,0xff,0xd2,0xd2,0xd2,0xd2
  ,0xd2,0x3b,0x3b,0x3b,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb
  ,0xdb,0xdb,0xff,0xff,0xd2,0xd2,0xd2,0xd2,0xd2,0x69,0x3b,0x3b,0xdb,0xdb
  ,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xdb,0xff,0xff,0xd2,0xd2
  ,0xd2,0xd2,0xd2,0xd2,0x3b,0x3b
};

Unit floorHeightAt(int16_t x, int16_t y)
{
  for (uint16_t i = 0; i < MAX_CHANGES; ++i)
    if (changes[i].mCoords.x == x && changes[i].mCoords.y == y)
      return changes[i].mHeight;

  return (heightProfile[absVal(x) % HEIGHT_PROFILE_LENGTH] +
         heightProfile[absVal(y + 20) % HEIGHT_PROFILE_LENGTH]) *
         UNITS_PER_SQUARE;
}

uint16_t previousColumn = 255;
uint16_t backgroundColumn = 0;

/**
  Function for drawing a single pixel (like fragment shader).
*/
inline void pixelFunc(PixelInfo pixel)
{
  uint8_t c = 0;

  int16_t intensity = 0;

  if (pixel.isWall)
  {
    c = pixel.hit.square.x != selectedSquare.x || pixel.hit.square.y != selectedSquare.y || (editing && pokitto.frameCount % 2) == 0 ? 50 : 30;
    
    intensity = pixel.depth / (UNITS_PER_SQUARE * 3);
    intensity += pixel.hit.direction % 2 == 0 ? 2 : 0;
  }
  else if (pixel.isFloor)
  {
    c = floorColor;

    if (!pixel.isHorizon)
      intensity = pixel.depth / (UNITS_PER_SQUARE * 3);
  }
  else
  {
    if (previousColumn == pixel.position.x)
    {
      c = imageBackground[2 + backgroundColumn * 22 + min(pixel.position.y,43) / 2];
    }
    else
    {
      backgroundColumn = absVal(pixel.position.x / 2 + (110 * player.mCamera.direction) / UNITS_PER_SQUARE) % 55;
      previousColumn = pixel.position.x;
    }
  }

  if (intensity != 0)
    c = addIntensity(c,intensity);

  uint8_t *buf = pokitto.display.screenbuffer;

  buf += pixel.position.x * SUBSAMPLE;
  buf += pixel.position.y * SCREEN_WIDTH;

  for (uint8_t i = 0; i < SUBSAMPLE - 1; ++i)
    *buf++ = c;

  *buf = c;
}

void draw()
{
  RayConstraints c;

  c.maxHits = 6;
  c.maxSteps = 20;
  c.computeTextureCoords = 0;

  render(player.mCamera,floorHeightAt,0,0,pixelFunc,c);
/*
pokitto.display.setColor(rgbToIndex(7,7,3));
pokitto.display.setCursor(1,1);
pokitto.display.print(player.mCamera.position.x);
pokitto.display.print(" ");
pokitto.display.print(player.mCamera.position.y);
pokitto.display.print(" ");
pokitto.display.print(player.mCamera.direction);
*/
}

int main()
{
  initGeneral();

  floorColor = rgbToIndex(4,2,0);

  player.setPositionSquare(4,5);

  for (uint16_t i = 0; i < MAX_CHANGES; ++i)
  {
    changes[i].mCoords.x = 0;
    changes[i].mCoords.y = 0;
    changes[i].mHeight = floorHeightAt(0,0);
  }

  uint32_t previousTime = 0;
  uint32_t dt;

  while (pokitto.isRunning())
  {
    if (pokitto.update())
    {
      draw();

      uint32_t timeNow = pokitto.getTime();
      dt = timeNow - previousTime;
      previousTime = timeNow;

      int16_t horizontalStep = (dt * PLAYER_SPEED * (player.mRunning ? 2 : 1)) / 1000;
      int16_t rotationStep = (dt * PLAYER_ROTATION_SPEED) / 1000;

      Vector2D d = angleToDirection(player.mCamera.direction);

      Vector2D facingOffset;

      if (player.mCamera.direction > (4 * UNITS_PER_SQUARE / 12) &&
        player.mCamera.direction <= (8 * UNITS_PER_SQUARE / 12))
        facingOffset.x = -1;
      else if (player.mCamera.direction < (2 * UNITS_PER_SQUARE / 12) ||
        player.mCamera.direction >= (10 * UNITS_PER_SQUARE / 12))
        facingOffset.x = 1;
      else
        facingOffset.x = 0;

      if (player.mCamera.direction > (UNITS_PER_SQUARE / 12) &&
        player.mCamera.direction <= (5 * UNITS_PER_SQUARE / 12))
        facingOffset.y = -1;
      else if (player.mCamera.direction > (6 * UNITS_PER_SQUARE / 12) &&
        player.mCamera.direction <= (11 * UNITS_PER_SQUARE / 12))
        facingOffset.y = 1;
      else
        facingOffset.y = 0;

      selectedSquare.x = divRoundDown(player.mCamera.position.x,UNITS_PER_SQUARE) + facingOffset.x;
      selectedSquare.y = divRoundDown(player.mCamera.position.y,UNITS_PER_SQUARE) + facingOffset.y;

      Vector2D moveOffset;
 
      moveOffset.x = 0;
      moveOffset.y = 0;

      d.x = (d.x * horizontalStep) / UNITS_PER_SQUARE;
      d.y = (d.y * horizontalStep) / UNITS_PER_SQUARE;

      if (d.x == 0 && d.y == 0)
      {
        d.x = d.x > 0 ? horizontalStep : -1 * horizontalStep;
        d.y = d.y > 0 ? horizontalStep : -1 * horizontalStep;
      }

      bool aButton = pokitto.aBtn();

      if (pokitto.cBtn())
      {
        if (editReleased)
        {
          editing = !editing;

          changeIndex = (changeIndex + 1) % MAX_CHANGES;

          for (uint16_t i = 0; i < MAX_CHANGES; ++i)
            if (changes[i].mCoords.x == selectedSquare.x &&
                changes[i].mCoords.y == selectedSquare.y)
            {
              changeIndex = i;
              break;
            }

          changes[changeIndex].mHeight = floorHeightAt(selectedSquare.x,selectedSquare.y);
          changes[changeIndex].mCoords.x = selectedSquare.x;
          changes[changeIndex].mCoords.y = selectedSquare.y;
          editReleased = false;
        }
      }
      else
        editReleased = true;

      if (pokitto.upBtn())
      {
        if (editing)
        {
          changes[changeIndex].mHeight += 100;
        }
        else if (aButton)
          player.mCamera.shear = min(player.mCamera.shear + 10,60);
        else
          moveOffset = d;
      }
      else if (pokitto.downBtn())
      {
        if (editing)
        {
          changes[changeIndex].mHeight -= 100;
        }
        else if (aButton)
          player.mCamera.shear = max(player.mCamera.shear - 10,-60);
        else
        {
          moveOffset.x = -1 * d.x;
          moveOffset.y = -1 * d.y;
        }
      }
      else
        player.mCamera.shear /= 2;
      
      if (!aButton)  
        player.mCamera.shear /= 2;

      int addition = 0;

      if (pokitto.rightBtn())
        addition = 1;      
      else if (pokitto.leftBtn())
        addition = -1;

      if (aButton)
      {
        d = angleToDirection(player.mCamera.direction + UNITS_PER_SQUARE / 4);
        d.x = (d.x * horizontalStep * addition) / UNITS_PER_SQUARE;
        d.y = (d.y * horizontalStep * addition) / UNITS_PER_SQUARE;

        moveOffset = d;
      }
      else
        player.mCamera.direction = wrap(player.mCamera.direction + addition * rotationStep,UNITS_PER_SQUARE);
    
      Unit prevHeight = player.mCamera.height;

      moveCameraWithCollision(&player.mCamera,moveOffset,player.mVericalSpeed,
        floorHeightAt, 0, 1);

      Unit heightDiff = player.mCamera.height - prevHeight;

      if (heightDiff == 0)
        player.mVericalSpeed = 0; // hit floor/ceiling

      if (player.mVericalSpeed == 0 && pokitto.bBtn())
      {
        int16_t camX = divRoundDown(player.mCamera.position.x,UNITS_PER_SQUARE);
        int16_t camY = divRoundDown(player.mCamera.position.y,UNITS_PER_SQUARE);

        if (player.mCamera.height - CAMERA_COLL_HEIGHT_BELOW -
          floorHeightAt(camX,camY) < 2)
          player.mVericalSpeed = JUMP_SPEED; // jump
      } 

      player.mVericalSpeed -= (dt * GRAVITY_ACCELERATION) / 1000; // gravity
    }
  }

  return 0;
}