Question: Why is GameMaker so laggy?

Answer

Lag in GameMaker can be attributed to a variety of factors, often related to the design and complexity of the game being developed, as well as the performance of the hardware it is running on. Here are some common reasons and solutions for lag in GameMaker:

1. Unoptimized Code: If your code is not optimized, GameMaker games can become slow, especially if you have complex loops or algorithms that run every step.

   // Example of unoptimized code that checks collision in a non-efficient way
   for (var i = 0; i < instance_number(obj_enemy); i++) {
       var inst = instance_find(obj_enemy, i);
       if (place_meeting(x, y, inst)) {
           // Collision response
       }
   }

   To optimize this, consider using spatial grids, quad trees, or built-in functions like instance_place() that are more efficient.

2. Too Many Objects: Creating an excessive number of objects can cause slowdowns due to the processing required to handle them all. Try to minimize the active instances in your game at any time.

3. Graphics Overload: High-resolution sprites and backgrounds, especially when not properly sized or optimized, can lead to a high draw call count which causes lag.

   • Use smaller texture pages and clean, scaled graphics.
   • Use sprite culling to avoid rendering off-screen instances.

4. Inefficient Event Usage: Using Step events for actions that don't need to be checked or updated every frame can lead to unnecessary calculations.

   • Move code to Begin Step or End Step events where appropriate.
   • Use alarms or custom variables to create timers instead of checking conditions each step.

5. Physics Engine Overload: If you're using the built-in physics engine, having too many physics calculations or complex shapes can slow down the game.

   • Simplify collision masks.
   • Deactivate physics on objects that don’t require it.

6. Large Rooms or Levels: Very large rooms with many elements can be taxing on performance.

   • Split large levels into smaller sections.
   • Implement object activation/deactivation based on proximity to the player's view.

7. Shader Complexity: Complex shaders can cause a significant drop in frames per second (FPS) if they're not well-optimized or are being run on lower-end hardware.

8. Not Utilizing Built-in Functions: GameMaker provides many built-in functions that are highly optimized. Not using them can result in slower performance.

9. Poor Resource Management: Loading and unloading resources improperly can cause memory leaks and increase the CPU's workload.

   • Use sprite_delete(), texture_delete(), and similar functions to manage resource lifecycles.

10. Hardware Limitations: The computer or device's GPU and CPU may not be powerful enough to run the game smoothly.

11. GameMaker Version: Always ensure that you're using the latest version of GameMaker, as updates typically include performance improvements and bug fixes.

If your GameMaker project is experiencing lag, it’s a good idea to profile your game using the built-in debugger tools. This will help you identify bottlenecks in your game's performance and guide you towards the specific issues that need addressing.