GMS2: Large Sprites Break Tileset_get_texture

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GMS2: Large Sprites Break `tileset_get_texture`

Introduction

Hey guys! Today, we're diving deep into a quirky issue in GameMaker Studio 2 (GMS2) that can drive you nuts if you're not prepared: very large animated sprites messing with the tileset_get_texture function. Imagine spending hours crafting beautiful sprites, only to find out they're causing texture glitches. Sounds frustrating, right? Well, buckle up, because we're going to explore what causes this problem, how to reproduce it, and potential workarounds to keep your game development smooth. Whether you're a seasoned developer or just starting, understanding these nuances can save you a ton of headache.

Understanding the Issue

So, what's the deal? The problem arises when you introduce very large sprite sheets into your project. Specifically, the tileset_get_texture function, which is often used in shaders to set the stage texture, starts behaving unexpectedly. Instead of pulling the correct texture data, it seems to grab the wrong stuff, leading to visual anomalies in your game. This issue appears to be specific to GMS2, as it doesn't manifest in GameMaker: Studio 1.x (GMRT). It’s like the function gets overwhelmed by the sheer size of the sprite sheets and starts mixing things up. For example, if you're using tileset_get_texture to create a rim lighting effect, you might notice that the lighting is completely off, creating an unintended and unpleasant visual effect. This can be particularly jarring if you have carefully designed your lighting to enhance the atmosphere of your game. The inconsistency between GMS2 and GMRT suggests that there might be differences in how the texture management is handled internally, with GMS2 struggling more with larger assets. Therefore, it's crucial to be aware of this limitation and plan your asset creation accordingly.

The Technical Details

Description

When you add two very large sprite sheets to your project, the tileset_get_texture function used in a shader to set the stage texture seems to be using incorrect texture data on GMS2 only (Seems fine in GMRT).

It's assumed the issue happens in obj_light_manager create event line 59.

Steps to Reproduce

  1. Run the project and GMS2 target and see issue where rimlighting texture is incorrect.
  2. Delete the assets spr_explosion and spr_explosion_blurred_edges OR run the project on GMRT target and rim lighting works as expected.

Environment

  • GameMaker Version: IDE v2024.1400.2.936 Runtime v2024.1400.2.921
  • Operating System: Windows 10.0.26100.0
  • Platforms Affected: GX.games, Windows

Diving Deeper: Reproducing the Bug with Large Animated Sprites

To really get a handle on this tileset_get_texture issue, let's break down the steps to reproduce it. This way, you can see firsthand what's going on and better understand how to avoid it in your own projects. First, you need a GameMaker Studio 2 (GMS2) project where you're using shaders and the tileset_get_texture function to, say, create a cool rim lighting effect. Now, introduce two massive animated sprites. These aren't your typical small sprites; we're talking about large sprite sheets with lots of frames, like detailed explosions or complex character animations. Once these sprites are in your project, run it, specifically targeting the GMS2 environment. What you'll likely see is that the rim lighting texture, or whatever texture you're manipulating with the shader, looks totally off. It's as if the texture data is being pulled from the wrong place, resulting in visual glitches. A quick way to verify that the large sprites are the culprit is to remove them from the project. If you delete spr_explosion and spr_explosion_blurred_edges, or similar large sprites, and run the project again, the rim lighting should magically start working as expected. Alternatively, you can run the same project in GameMaker: Studio 1.x (GMRT). You should find that the issue doesn't occur there, further pinpointing the problem to how GMS2 handles these large assets. By following these steps, you can reliably reproduce the bug and confirm that it's indeed related to the presence of large animated sprites.

Why Large Sprites Cause Problems

The million-dollar question is, why do large sprites cause problems with tileset_get_texture in GMS2? The exact reason isn't always clear-cut, but we can make some educated guesses based on how game engines handle textures and memory. When you load a large sprite into GameMaker, it's essentially loading a big chunk of image data into memory. This data needs to be managed efficiently to ensure that the game runs smoothly, especially on lower-end devices. One possibility is that GMS2's texture management system struggles when dealing with extremely large textures. The tileset_get_texture function might be trying to access data that's either not properly loaded or is being overwritten due to memory constraints. Another factor could be related to texture page swapping. GameMaker divides textures into pages to optimize memory usage. When a sprite is too large, it might span multiple texture pages, and the tileset_get_texture function could be failing to correctly handle these page boundaries, leading to incorrect texture sampling. Additionally, there might be underlying differences in how GMS2 and GMRT handle texture compression and caching. GMS2 might be using more aggressive compression techniques that, while saving memory, introduce artifacts or cause issues with texture access when dealing with very large sprites. Finally, shader compilation and optimization could also play a role. The shader code that uses tileset_get_texture might be compiled differently in GMS2 compared to GMRT, leading to different performance characteristics and potential bugs when handling large texture data. Understanding these potential causes can help you make informed decisions about how to structure your assets and optimize your game for better performance and stability.

Potential Workarounds for Large Sprite Issues

Okay, so you're stuck with large sprites and need a fix. What can you do? Don't worry, there are several workarounds you can try to mitigate the issues caused by large sprites and the tileset_get_texture function in GMS2. One of the most straightforward solutions is to split your large sprites into smaller chunks. Instead of having one massive sprite sheet, break it down into multiple smaller sheets. This reduces the memory overhead for each individual texture and can help GMS2 manage the data more efficiently. When drawing the sprite, you'll need to adjust your code to handle the different sprite sheets, but it's often a worthwhile trade-off. Another approach is to optimize your sprite sheets as much as possible. Ensure that you're using the most efficient image format (e.g., PNG with minimal color depth) and that you're not including unnecessary empty space around your sprites. Compressing your sprites can also reduce their memory footprint, but be careful with lossy compression formats like JPEG, as they can introduce artifacts that degrade the visual quality. If you're using the tileset_get_texture function in a shader, consider simplifying your shader code. Complex shaders can exacerbate the issues caused by large textures, so try to reduce the number of calculations and texture lookups. You might also experiment with different texture filtering modes to see if they improve performance. Furthermore, consider using texture arrays if your game engine supports them. Texture arrays allow you to store multiple textures in a single array, which can be more efficient than using individual textures. Finally, keep an eye on GameMaker Studio 2 updates. YoYo Games is constantly working to improve the engine, and they may release fixes that address the issues with large sprites and texture management. By trying these workarounds, you can often find a solution that allows you to use large sprites without sacrificing performance or visual quality.

Practical Tips for Managing Large Sprites in GMS2

Dealing with large sprites in GameMaker Studio 2 (GMS2) requires a strategic approach to ensure smooth performance and prevent issues like the tileset_get_texture bug. Here are some practical tips to help you manage these assets effectively. First and foremost, optimize your workflow for creating and importing sprites. Use external image editing tools like Photoshop or GIMP to prepare your sprites before importing them into GMS2. Make sure to remove any unnecessary layers, reduce the color depth to the minimum required for your visual style, and crop the images to eliminate excess transparent pixels. This can significantly reduce the file size of your sprites. When organizing your project, consider using sprite collections to group related sprites together. This can help you keep your asset library organized and make it easier to find and manage your sprites. Additionally, take advantage of GMS2's built-in texture groups to control how your textures are packed and optimized. Experiment with different texture group settings to find the best balance between memory usage and performance for your project. Another important tip is to profile your game regularly to identify performance bottlenecks. Use GMS2's profiler to monitor CPU and GPU usage, and pay attention to the memory footprint of your textures. If you notice that your game is running slowly or that memory usage is too high, try reducing the size or number of large sprites in your project. Finally, stay informed about the latest updates and best practices for GMS2. YoYo Games often releases updates with performance improvements and bug fixes, so make sure to keep your IDE and runtime up to date. By following these practical tips, you can effectively manage large sprites in GMS2 and create visually stunning games without sacrificing performance.

Conclusion

In conclusion, while large animated sprites can indeed cause headaches with functions like tileset_get_texture in GameMaker Studio 2, understanding the root causes and applying practical workarounds can help you overcome these challenges. By splitting large sprites, optimizing your sprite sheets, simplifying shader code, and staying informed about engine updates, you can effectively manage your assets and maintain a smooth development process. Remember, a strategic approach to asset management is key to creating visually impressive and performant games. Happy game making, guys!