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Tilemaps can now load their own physics engines from map properties. The gravity for the arcade simulation is acting a little funny when populated from the map properties.

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This commit is contained in:
Andrew Kesterson
2026-06-02 17:11:16 -04:00
parent 9fed59c4c8
commit 652ee4cdf3
7 changed files with 221 additions and 76 deletions
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50
src/physics.c
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@@ -47,14 +47,20 @@ akerr_ErrorContext AKERR_NOIGNORE *akgl_physics_arcade_gravity(akgl_PhysicsBacke
PREPARE_ERROR(e);
FAIL_ZERO_RETURN(e, self, AKERR_NULLPOINTER, "self");
FAIL_ZERO_RETURN(e, actor, AKERR_NULLPOINTER, "actor");
// Assume the X origin is - (screen left)
actor->ex -= (self->gravity_x * dt);
// Assume Y origin is + (down screen)
actor->ey += (self->gravity_y * dt);
// Assume Z origin is - (behind the camera)
actor->ez -= (self->gravity_z * dt);
if ( self->gravity_x != 0 ) {
// Assume the X origin is - (screen left)
actor->ex -= (self->gravity_x * dt);
}
if ( self->gravity_y != 0 ) {
// Assume Y origin is + (down screen)
actor->ey += (self->gravity_y * dt);
}
if ( self->gravity_z != 0 ) {
// Assume Z origin is - (behind the camera)
actor->ez -= (self->gravity_z * dt);
}
SUCCEED_RETURN(e);
}
@@ -186,9 +192,15 @@ akerr_ErrorContext AKERR_NOIGNORE *akgl_physics_simulate(akgl_PhysicsBackend *se
PASS(e, self->gravity(self, actor, dt));
// Counteract velocity with atmospheric drag
actor->ex -= actor->ex * self->drag_x * dt;
actor->ey -= actor->ey * self->drag_y * dt;
actor->ez -= actor->ez * self->drag_z * dt;
if ( self->drag_x != 0 ) {
actor->ex -= actor->ex * self->drag_x * dt;
}
if ( self->drag_y != 0 ) {
actor->ey -= actor->ey * self->drag_y * dt;
}
if ( self->drag_z != 0 ) {
actor->ez -= actor->ez * self->drag_z * dt;
}
actor->vx = actor->ex + actor->tx;
actor->vy = actor->ey + actor->ty;
@@ -204,3 +216,21 @@ akerr_ErrorContext AKERR_NOIGNORE *akgl_physics_simulate(akgl_PhysicsBackend *se
self->gravity_time = curtime;
SUCCEED_RETURN(e);
}
akerr_ErrorContext AKERR_NOIGNORE *akgl_physics_factory(akgl_PhysicsBackend *self, akgl_String *type)
{
uint32_t hashval;
PREPARE_ERROR(e);
FAIL_ZERO_RETURN(e, self, AKERR_NULLPOINTER, "self");
FAIL_ZERO_RETURN(e, type, AKERR_NULLPOINTER, "type");
if ( strncmp(type->data, "null", 4) == 0) {
PASS(e, akgl_physics_init_null(self));
SUCCEED_RETURN(e);
}
if ( strncmp(type->data, "arcade", 6) == 0) {
PASS(e, akgl_physics_init_arcade(self));
SUCCEED_RETURN(e);
}
FAIL_RETURN(e, AKERR_KEY, "Invalid physics engine %s", type->data);
}