Bullet system added

1 files changed, 165 insertions, 0 deletions

diff --git a/src/bullets.c b/src/bullets.c
new file mode 100644
index 0000000..10116c2
--- /dev/null
+++ b/src/bullets.c
@@ -0,0 +1,165 @@
+#include "bullets.h"
+#include "game.h"
+
+Bullet createBullet(Entity entity, Vector3 direction, Vector3 offset, float damage) {
+	Bullet bullet = (Bullet){
+		.hit = false,
+		.ray = (Ray){
+			.position = Vector3Add(entity.position, offset),
+			.direction = direction,
+		},
+		.fromId = entity.id,
+		.fromFingerprint = entity.fingerprint,
+		.damage = damage
+	};
+
+	return bullet;
+}
+
+void initBullets(Bullets * bullets) {
+	bullets->bullets = NULL;
+	bullets->bulletsCount = 0;
+}
+
+void freeBullets(Bullets * bullets) {
+	if (bullets->bullets != NULL)
+		KF_FREE(bullets->bullets);
+}
+
+KfError addBullet(Bullets * bullets, Bullet bullet) {
+	// Not allocated yet.
+	if (bullets->bullets == NULL) {
+		bullets->bullets = (Bullet*)KF_CALLOC(1, sizeof(Bullet));
+
+		if (bullets->bullets == NULL) {
+			ALLOCATION_ERROR;
+			return KFERROR;
+		}
+
+		bullets->bulletsCount = 1;
+		bullets->bullets[0] = bullet;
+		return KFSUCCESS;
+	}
+
+	++bullets->bulletsCount;
+
+	// Reallocate.
+	bullets->bullets = (Bullet*)KF_REALLOCARRAY(
+		bullets->bullets, 
+		bullets->bulletsCount,
+		sizeof(Bullet)
+	);
+
+	if (bullets->bullets == NULL) {
+		ALLOCATION_ERROR;
+		return KFERROR;
+	}
+	
+	bullets->bullets[bullets->bulletsCount - 1] = bullet;
+	return KFSUCCESS;
+}
+
+KfError popBackBullets(Bullets * bullets) {
+	if (bullets->bullets == NULL)
+		return KFSUCCESS;
+
+	// At one.
+	if (bullets->bulletsCount == 1) {
+		KF_FREE(bullets->bullets);
+		bullets->bullets = NULL;
+		bullets->bulletsCount = 0;
+		return KFSUCCESS;
+	}
+
+	--bullets->bulletsCount;
+
+	// Reallocate.
+	bullets->bullets = (Bullet*)KF_REALLOCARRAY(
+		bullets->bullets, 
+		bullets->bulletsCount,
+		sizeof(Bullet)
+	);
+
+	if (bullets->bullets == NULL) {
+		ALLOCATION_ERROR;
+		return KFERROR;
+	}
+
+	return KFSUCCESS;
+}
+
+void updateBullets(Game * game, Bullets * bullets) {
+	int i;
+	Bullet * last = NULL;
+
+	if (bullets->bullets == NULL)
+		return;
+
+	// Update each bullet.
+	for (i = 0; i < bullets->bulletsCount; ++i)
+		updateBullet(game, &bullets->bullets[i]);
+
+	// Remove end if hit or out of bounds.
+	last = &bullets->bullets[bullets->bulletsCount - 1];
+
+	if (last->hit)
+		popBackBullets(bullets);
+	else if (Vector3Length(last->ray.position) >= GAME_BOUNDS)
+		popBackBullets(bullets);
+}
+
+void updateBullet(Game * game, Bullet * bullet) {
+	int i, j;
+	RayCollision collision;
+	Ray ray;
+	Entity * currentEntity;
+
+	// Already hit.
+	if (bullet->hit)
+		return;
+
+	// Set direction.
+	ray.direction = bullet->ray.direction;
+
+	// Check collision.
+	for (i = 0; i < game->world.entitiesCount; ++i) {
+		currentEntity = &game->world.entities[i];
+
+		// This was the entity that shot it.
+		if (currentEntity->fingerprint == bullet->fromFingerprint)
+			continue;
+		else if (currentEntity->model == NULL) // Null model indeed.
+			continue;
+
+		// Set position relative to entity.
+		ray.position = Vector3Subtract(bullet->ray.position, currentEntity->position);
+
+		// Loop through meshes.
+		for (j = 0; j < currentEntity->model->meshCount; ++j) {
+			collision = GetRayCollisionMesh(
+				ray,
+				currentEntity->model->meshes[j],
+				currentEntity->model->transform
+			);
+
+			// Did hit.
+			if (!collision.hit)
+				continue;
+
+			currentEntity->health -= bullet->damage;
+			bullet->hit = true;
+			goto afterCollisionCheck;
+		}
+	}
+
+afterCollisionCheck:
+
+	// Update position.
+	bullet->ray.position = Vector3Add(
+		bullet->ray.position,
+		bullet->ray.direction
+	);
+
+	// Debug ray (:
+	//DrawRay(bullet->ray, BLUE);
+}