GMR::Window

January 14, 2026 ยท View on GitHub

GMR Docs > Engine > Utilities > Window

GMR::Window

Window management and display settings.

Table of Contents

Functions

width

Get the logical width of the game screen in UI coordinate space. This is the width you should use for positioning UI elements. The engine uses a 360p baseline, so at 540p this returns 640 (960/1.5).

Returns: Integer - Logical screen width

Example:

screen_w = GMR::Window.width

height

Get the logical height of the game screen in UI coordinate space. This is the height you should use for positioning UI elements. The engine uses a 360p baseline, so this always returns 360.

Returns: Integer - Logical screen height (always 360 due to baseline)

Example:

screen_h = GMR::Window.height

screen_width

Get the actual screen width in pixels. Use this when you need real pixel dimensions (e.g., for shaders).

Returns: Integer - Screen width in pixels

Example:

pixels_w = GMR::Window.screen_width

screen_height

Get the actual screen height in pixels. Use this when you need real pixel dimensions (e.g., for shaders).

Returns: Integer - Screen height in pixels

Example:

pixels_h = GMR::Window.screen_height

actual_width

Get the actual window width in pixels, ignoring virtual resolution.

Returns: Integer - Actual window width

Example:

real_w = GMR::Window.actual_width

actual_height

Get the actual window height in pixels, ignoring virtual resolution.

Returns: Integer - Actual window height

Example:

real_h = GMR::Window.actual_height

set_size

Set the window size. Has no effect in fullscreen mode.

Parameters:

NameTypeDescription
wIntegerWindow width in pixels
hIntegerWindow height in pixels

Returns: Module - self for chaining

Example:

GMR::Window.set_size(1280, 720).set_title("My Game")

set_title

Set the window title bar text.

Parameters:

NameTypeDescription
titleStringThe window title

Returns: Module - self for chaining

Example:

GMR::Window.set_title("My Awesome Game")

toggle_fullscreen

Toggle between fullscreen and windowed mode.

Returns: Boolean - true

Example:

GMR::Window.toggle_fullscreen

fullscreen=

Set fullscreen mode on or off.

Parameters:

NameTypeDescription
fullscreenBooleantrue for fullscreen, false for windowed

Returns: Boolean - The fullscreen state that was set

Example:

GMR::Window.fullscreen = true

fullscreen?

Check if the window is currently in fullscreen mode.

Returns: Boolean - true if fullscreen

Example:

if GMR::Window.fullscreen?
  show_windowed_mode_button
end

set_virtual_resolution

Set a virtual resolution for pixel-perfect rendering. The game renders to this resolution and scales to fit the window with letterboxing.

Parameters:

NameTypeDescription
wIntegerVirtual width in pixels
hIntegerVirtual height in pixels

Returns: Module - self for chaining

Example:

# Render at 320x240 for retro-style game
  GMR::Window.set_virtual_resolution(320, 240).set_filter_point

clear_virtual_resolution

Disable virtual resolution and render directly at window size.

Returns: Module - self for chaining

Example:

GMR::Window.clear_virtual_resolution

virtual_resolution?

Check if virtual resolution is currently enabled.

Returns: Boolean - true if virtual resolution is active

Example:

if GMR::Window.virtual_resolution?
  puts "Using virtual resolution"
end

set_filter_point

Set nearest-neighbor (point) filtering for virtual resolution scaling. Produces crisp, pixelated look. Only works when virtual resolution is enabled.

Returns: Module - self for chaining

Example:

GMR::Window.set_virtual_resolution(320, 240).set_filter_point

set_filter_bilinear

Set bilinear filtering for virtual resolution scaling. Produces smoother, blended scaling. Only works when virtual resolution is enabled.

Returns: Module - self for chaining

Example:

GMR::Window.set_virtual_resolution(320, 240).set_filter_bilinear

use_native_dpr

Enable high-DPI rendering at native device pixel ratio. Results in sharper rendering on retina displays but may impact performance. Only affects web builds. On native platforms this has no effect.

Returns: Module - self for chaining

Example:

GMR::Window.use_native_dpr  # Enable sharp retina rendering

use_css_dpr

Render at CSS pixel resolution (1:1 with layout pixels). Better performance on high-DPI displays but may appear less sharp. This is the default behavior. Only affects web builds.

Returns: Module - self for chaining

Example:

GMR::Window.use_css_dpr  # Default, better performance

device_pixel_ratio

Get the current device pixel ratio. Returns 1.0 on standard displays, 2.0 on retina displays, etc. On native platforms, always returns 1.0.

Returns: Float - Device pixel ratio

Example:

dpr = GMR::Window.device_pixel_ratio  # 2.0 on retina

native_dpr?

Check if native DPR rendering is enabled.

Returns: Boolean - true if rendering at native device pixel ratio

Example:

if GMR::Window.native_dpr?
  puts "Rendering at #{GMR::Window.device_pixel_ratio}x resolution"
end

monitor_count

Get the number of connected monitors.

Returns: Integer - Number of monitors

Example:

count = GMR::Window.monitor_count

monitor_width

Get the width of a specific monitor.

Parameters:

NameTypeDescription
indexIntegerMonitor index (0-based)

Returns: Integer - Monitor width in pixels

Example:

w = GMR::Window.monitor_width(0)  # Primary monitor

monitor_height

Get the height of a specific monitor.

Parameters:

NameTypeDescription
indexIntegerMonitor index (0-based)

Returns: Integer - Monitor height in pixels

Example:

h = GMR::Window.monitor_height(0)

monitor_refresh_rate

Get the refresh rate of a specific monitor.

Parameters:

NameTypeDescription
indexIntegerMonitor index (0-based)

Returns: Integer - Refresh rate in Hz

Example:

hz = GMR::Window.monitor_refresh_rate(0)

monitor_name

Time and frame rate utilities. Provides delta time for frame-independent movement, elapsed time tracking, and FPS management.

Parameters:

NameTypeDescription
indexIntegerMonitor index (0-based)

Returns: String - Monitor name

Example:

# Debug overlay with FPS and timing info
  class DebugOverlay
    def draw
      y = 10
      color = [0, 255, 0]

      # Show current FPS
      fps = GMR::Time.fps
      fps_color = fps < 30 ? [255, 0, 0] : fps < 55 ? [255, 255, 0] : [0, 255, 0]
      GMR::Graphics.draw_text("FPS: #{fps}", 10, y, 16, fps_color)
      y += 20

      # Show frame time
      frame_ms = (GMR::Time.delta * 1000).round(2)
      GMR::Graphics.draw_text("Frame: #{frame_ms}ms", 10, y, 16, color)
      y += 20

      # Show total elapsed time
      elapsed = GMR::Time.elapsed
      minutes = (elapsed / 60).to_i
      seconds = (elapsed % 60).to_i
      GMR::Graphics.draw_text("Time: #{minutes}:#{seconds.to_s.rjust(2, '0')}", 10, y, 16, color)
    end
  end

set_vsync(arg1)

TODO: Add documentation

Parameters:

NameTypeDescription
arg1Boolean

Returns: unknown

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