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#include "../include/playerObject.h"
void initializePlayerObject (playerObject *object) {
// Initialize the point and velocity of a player object
object->vel = createVelocity(0, 0);
object->pt = createPoint(15 << FIX_SHIFT, 0 << FIX_SHIFT);
}
playerObject createPlayerObject (OBJ_ATTR *obj_buffer, OBJ_AFFINE *affine_buffer, int pallete_bank, int tile_id) {
// Create a player object from data
obj_affine_identity(affine_buffer);
playerObject temp;
initializePlayerObject(&temp);
temp.rotation = 0;
temp.obj = obj_buffer;
temp.affine = affine_buffer;
temp.pallete_bank = pallete_bank;
temp.tile_id = tile_id;
temp.isJumping = 0;
obj_set_attr(temp.obj,
ATTR0_SQUARE | ATTR0_AFF | ATTR0_AFF_DBL_BIT, // Set attribute 1 to be a square using affine and double size
ATTR1_SIZE_16 | ATTR1_AFF_ID(0), // Set size to 16 x 16
ATTR2_PALBANK(pallete_bank) | tile_id // Which pallete to use, as we are in
// 16-color mode
);
obj_set_pos(temp.obj, temp.pt.x >> FIX_SHIFT, temp.pt.y >> FIX_SHIFT);
return temp;
}
void applyGravity (playerObject *object) {
// Apply a gravity constant to a player
object->vel.dy += float_to_fixed(GRAVITY);
// This is a weird convention to have gravity in the positive direction,
// but I don't want to deal with coordinate changing. Too lazy
}
void scalePlayer (playerObject *object, u32 scaleX, u32 scaleY) {
// Scale the player's sprite
// Maximum 0.5
object->affine->pa = scaleX; object->affine->pb = 0 ;
object->affine->pc = 0 ; object->affine->pd = scaleY;
}
void rotatePlayer (playerObject *object) {
// Rotate the player's sprite
int sinAlpha = lu_sin(object->rotation >> 4) >> 4;
int cosAlpha = lu_cos(object->rotation >> 4) >> 4;
object->affine->pa = cosAlpha; object->affine->pb =-sinAlpha;
object->affine->pc = sinAlpha; object->affine->pd = cosAlpha;
}
void rotateToNearest90Degrees(playerObject *object) {
// Round a rotation to the nearest 90 degree equivalent of "binary radians"
// (Where 2pi = 0xFFFF and 0pi = 0)
u32 rotation = object->rotation;
u32 twoPi = 0xFFFF << 4;
u32 pi = 0x8000 << 4;
u32 halfPi = 0x4000 << 4;
u32 quarterPi = 0x2000 << 4;
if (rotation > quarterPi && rotation < 3 * quarterPi) {
object->rotation = halfPi;
}
else if (rotation > 3 * quarterPi && rotation < (pi + quarterPi)) {
object->rotation = pi;
}
else if (rotation > (pi + quarterPi) && rotation < (pi + 3*quarterPi)) {
object->rotation = pi + halfPi;
}
else if (rotation < quarterPi || rotation > (twoPi - quarterPi)) {
object->rotation = 0;
}
}
void updatePlayer (playerObject *object, u32 GROUND_LEVEL) {
// Update the position of a player object
updatePoint(&object->pt, &object->vel);
if (object->pt.y >> FIX_SHIFT >= GROUND_LEVEL) {
// Only apply gravity if player is not touching the ground
object->isJumping = 0;
object->pt.y = GROUND_LEVEL << FIX_SHIFT; // Don't go through ground
object->vel.dy = 0;
rotateToNearest90Degrees(object);
}
else {
object->isJumping = 1;
applyGravity(object);
object->rotation += 100 << 8;
}
rotatePlayer(object);
// Update the player object's attributes' position and subtract 8 pixels in
// both axes because the sprite is using the DBL_BIT for attr0
obj_set_pos(object->obj, (object->pt.x >> FIX_SHIFT) - 8, (object->pt.y >> FIX_SHIFT) - 9);
// Update the player's second attribute (tile and pallete bank)
object->obj->attr2 = ATTR2_BUILD(object->tile_id, object->pallete_bank, 0);
}
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