How to Make a Top Down Shooter in GameMaker Studio 2! (Part 1: Movement and Collision)

Summary of "How to Make a Top Down Shooter in GameMaker Studio 2! (Part 1: Movement and Collision)"

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Overview

• This video is the first episode in a 13-part beginner-friendly series teaching how to create a top-down shooter game using GameMaker Studio 2.
• The series aims to improve viewers’ game development skills with in-depth explanations.
• Videos are released twice a week, with early access and project files available on Patreon.
• The creator is also working on two personal games, including an Action RPG titled Star-Crossed Starcade Special.

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Key Technological Concepts & Product Features Covered

1. Project Setup and Asset Management

• Starting a new GameMaker Studio 2 project.
• Cleaning up default folders to reduce visual clutter.
• Creating and editing sprites (player and walls) using the built-in image editor.
• Setting sprite origin points (center for player, top-left for walls) to simplify positioning and scaling.
• Understanding and adjusting collision masks for sprites.

2. Room and Viewport Configuration

• Setting room size to 640x360 pixels (16:9 aspect ratio) for pixel-perfect scaling.
• Adjusting grid size to 16x16 pixels to align objects and sprites.
• Configuring viewports and cameras for pixel-perfect display and scaling the viewport to double size for better visibility on 1080p monitors.
• Explaining the difference between room size and camera/viewport size.

3. Player Object Creation

• Creating a player object and assigning the player sprite.
• Placing player instances in the room using instance layers.
• Explaining how multiple instances of the same object can exist in a room.

4. Player Movement Implementation

• Using the Create event to initialize movement variables:
  • moveDirection (360-degree movement direction)
  • moveSpeed (default speed set to 2 pixels/frame)
  • xSpeed and ySpeed for directional movement components.
• Using the Step event (runs every frame) to:
  • Read keyboard inputs (WASD or arrow keys) using keyboard_check() function.
  • Calculate horizontal and vertical input directions (rightKey - leftKey, downKey - upKey).
  • Use point_direction() function to convert input into a 360-degree movement direction.
  • Use point_distance() to determine input magnitude (input level).
  • Clamp input level to avoid faster diagonal movement (normalizing diagonal speed).
  • Calculate xSpeed and ySpeed using lengthdir_x() and lengthdir_y() functions based on speed and direction.
  • Update player position by adding xSpeed and ySpeed to coordinates.
• Explanation of why consistent movement speed in all directions is important for gameplay fairness and player experience, especially in action games and for controller support.

5. Collision Handling

• Creating two types of wall sprites and objects:
  • Yellow walls (generic walls, e.g., pits or water that block players/enemies but not projectiles).
  • Red solid walls (block everything including projectiles).
• Setting wall sprite origins to top-left for easy placement.
• Player object handles collision detection using place_meeting() function:
  • Separately checking X and Y movement for collisions.
  • If collision detected on X or Y axis, respective speed is set to zero to prevent movement into walls.
• Introducing GameMaker’s parenting system:
  • Making solid wall a child of the generic wall object.
  • Allows collision checks against the parent to include all child objects, reducing redundant collision checks and improving performance.
  • Explains how this system helps differentiate between collision types (e.g., bullets ignoring pits but colliding with solid walls).

6. Known Limitations and Future Improvements

• Noted that current collision handling can cause small gaps due to speed and collision precision.
• More precise collision handling (e.g., sub-pixel or loop-based collision resolution) will be covered in future episodes once foundational knowledge is solidified.

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Additional Notes

• The video encourages beginners to watch the creator’s RPG series for foundational knowledge on GameMaker functions and concepts.
• The tutorial balances simplicity with enough complexity to prepare for controller input and more advanced game mechanics.
• The creator promotes Patreon for early access, project files, and community support.
• Plans for a live stream and additional creative development on the project post-series are mentioned.
• The creator is actively developing and releasing their own games, with links and social media for follow-up.

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Main Speaker / Source

• The tutorial is presented by an experienced GameMaker Studio 2 developer and YouTuber (name not explicitly mentioned in subtitles but known from context as "Nixionic").
• The speaker provides clear, step-by-step instructions with explanations of functions, variables, and game design considerations.