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implement basic collision and interpolation #6

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Sara merged 7 commits from collision into main 2023-06-18 11:51:16 +00:00
Conversation 0 Commits 7 Files Changed 2
2 changed files with 32 additions and 19 deletions
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50
src/corelib/world.c
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@ -110,7 +110,7 @@ static inline
short _collision_circle_aabb(const object_t* circle, const object_t* aabb) {
// generate a point on the edge of the rectangle that is closest to the circle
const float bbminx = aabb->collider.aabb.x + aabb->sprite.x, bbmaxx = bbminx + aabb->collider.aabb.w,
bbminy = aabb->collider.aabb.y + aabb->sprite.x, bbmaxy = bbminy + aabb->collider.aabb.h;
bbminy = aabb->collider.aabb.y + aabb->sprite.y, bbmaxy = bbminy + aabb->collider.aabb.h;
const float cx = circle->sprite.x + circle->collider.circle.x,
cy = circle->sprite.y + circle->collider.circle.y;
const float x = fclampf(cx, bbminx, bbmaxx),
@ -141,7 +141,13 @@ short _collision_check(const object_t* a, const object_t* b) {
static inline
short _can_collide(const object_t* object) {
return object->active && object->enabled && object->collider.evt_collision != NULL;
return object->active && object->enabled;
}
void object_broadcast_collision(object_t* this, object_t* other) {
if(this->collider.evt_collision != NULL) {
this->collider.evt_collision(this, other);
}
}
void update_collision() {
@ -153,8 +159,8 @@ void update_collision() {
if(!_can_collide(oobject)) continue;
if(outer != inner && _collision_check(iobject, oobject)) {
oobject->collider.evt_collision(oobject, iobject);
iobject->collider.evt_collision(iobject, oobject);
object_broadcast_collision(oobject, iobject);
object_broadcast_collision(iobject, oobject);
}
}
}
@ -170,35 +176,41 @@ object_t* interpolate_move(object_t* object, float target_x, float target_y, flo
// ensure this object would ever collide
// if it wouldn't collide anyway, just set position
if(_can_collide(object)) {
if(!_can_collide(object)) {
object->sprite.x = target_x;
object->sprite.y = target_y;
return NULL;
}
/*
* 1. check collision with every other object
* 2. move towards target
* 1. move towards target
* 2. check collision with every other object
*/
while(object->sprite.x != target_x || object->sprite.y != target_y) {
for(int i = 0; i < WORLD_NUM_OBJECTS; ++i) {
object_t* other = g_objects + i;
if(!_can_collide(other)) continue;
if(object != other && _collision_check(other, object)) {
other->collider.evt_collision(other, object);
object->collider.evt_collision(object, other);
return other;
}
}
// move towards target, snap to target if distance is too low
float distx = fabsf(object->sprite.x - target_x), disty = fabsf(object->sprite.y - target_y);
const float old_x = object->sprite.x, old_y = object->sprite.y;
const float distx = fabsf(object->sprite.x - target_x), disty = fabsf(object->sprite.y - target_y);
if(distx < fabsf(dx) && disty < fabsf(dy)) {
object->sprite.x += dx; object->sprite.y += dy;
object->sprite.x += dx;
object->sprite.y += dy;
} else {
object->sprite.x = target_x;
object->sprite.y = target_y;
}
// loop over all objects and check collision if applicable
for(int i = 0; i < WORLD_NUM_OBJECTS; ++i) {
// get pointer to other object
object_t* other = g_objects + i;
// check collision, return if found
if(_can_collide(other) && object != other && _collision_check(other, object)) {
object_broadcast_collision(other, object);
object_broadcast_collision(object, other);
object->sprite.x = old_x;
object->sprite.y = old_y;
return other;
}
}
}
// no collision, return nothing

1
src/corelib/world.h
View File

@ -55,6 +55,7 @@ object_t* instantiate_object(const object_t* original);
collider_t collider_default();
void object_draw_sprite(object_t* object);
void object_broadcast_evt_collision(object_t* this, object_t* other);
void update_objects();
void draw_objects();