Bullet Trail Effect

bullet_effect_trail.dnh

task ManageEffectTrail(){
	// CreateShotA1(ObjMove_GetX(objEnemy),ObjMove_GetY(objEnemy), 2, 80, SHOT_RING_RED, 0);

	let num = 20;
	let delay = 1;

	let textures = [];
	let tex_objs = [];
	ascent(i in 0..num){
		textures = textures ~ ["EffectBuffer"~itoa(i)];
		CreateRenderTarget(textures[i]);
		tex_objs = tex_objs ~ [ makeTextureObject(textures[i]) ];
	}

	function makeTextureObject(texture){
		let obj = ObjPrim_Create(OBJ_SPRITE_2D);
		ObjRender_SetPosition(obj, 0, 0, 0);
		ObjPrim_SetTexture(obj, texture);
		ObjSprite2D_SetSourceRect(obj, 32, 16, 32+384, 16+448);
		ObjSprite2D_SetDestRect(obj, 0, 0, 384, 448);
		Obj_SetRenderPriorityI(obj, 49);
		return obj;
	}

	let c = 0;
	loop{ // exit condition?
		RenderToTextureA1(textures[c], 50, 50, true);

		ascent(i in 0..num){
			// Obj_SetRenderPriorityI( tex_objs[(c - i) % num], 49 - i );
			ObjRender_SetAlpha( tex_objs[(c - i) % num], 255 - 255*(i+1)/(num+1) );
		}
		
		c = (c + 1) % num;
		loop(delay){yield;}
	}

	ascent(i in 0..length(tex_objs)){ Obj_Delete(tex_objs[i]); }
}