Mednafen

Virtual Boy Documentation

Last updated December 31, 2010
Valid as of 0.9.16-WIP

Table of Contents:


Introduction

Virtual Boy ROM images must each have an extension of ".vb" or ".vboy" to be recognized as such. Mednafen versions prior to 0.9.13 allowed ".bin" as well, but this conflicts with the Sega Megadrive emulation module.

Due to how the left+right views are transformed into a single image, enabling most of the image filter effects(bilinear interpolation, OpenGL pixel shaders, special scalers, etc.) is not recommended. However, they will work properly with the "cscope" and "sidebyside" 3D modes, and may work tolerably with the "anaglyph" 3D mode. This limitation may be corrected in the future by refactoring the 3D mode mixing out to the driver side, post individual filtering for each left/right view; however, this would significantly negatively impact performance.

To use the "hli" mode with a "Line Interlaced 3D" monitor, you'll want to set "vb.yscale(fs)" to 1, "vb.liprescale" appropriately, and "vb.xscale(fs)" to 2 multiplied by the value of "vb.liprescale".

NOTE: The "hli" and "vli" modes will not work properly in windowed video output mode; you may need to adjust the window's position to get the lines to line up correctly for the 3D effect to work.


Settings Reference

Caution: Any settings that change emulation behavior as seen from the emulated game are shown with the setting name bolded in the table. One should be conscious of these settings if one has changed them from the default values when using network play or movies, as they can cause desychronizations if not set the same among hosts(or between the recording emulator and the playing emulator).

Setting:Value Type:Possible Values:Default Value:Description:
vb.3dmodeenumanaglyph
cscope
sidebyside
vli
hli
anaglyph3D mode.

  • anaglyph - Anaglyph
    Used in conjuction with classic dual-lens-color glasses.

  • cscope - CyberScope
    Intended for use with the CyberScope 3D device.

  • sidebyside - Side-by-Side
    The left-eye image is displayed on the left, and the right-eye image is displayed on the right.

  • vli - Vertical Line Interlaced
    Vertical lines alternate between left view and right view.

  • hli - Horizontal Line Interlaced
    Horizontal lines alternate between left view and right view.
 
vb.3dreverseboolean0
1
0Reverse left/right 3D views.

 
vb.allow_draw_skipboolean0
1
0Allow draw skipping.

If vb.instant_display_hack is set to "1", and this setting is set to "1", then frame-skipping the drawing to the emulated framebuffer will be allowed. THIS WILL CAUSE GRAPHICAL GLITCHES, AND THEORETICALLY(but unlikely) GAME CRASHES, ESPECIALLY WITH DIRECT FRAMEBUFFER DRAWING GAMES.

 
vb.anaglyph.lcolorinteger0x000000 through 0xFFFFFF0xffba00Anaglyph maximum-brightness color for left view.

 
vb.anaglyph.presetenumdisabled
red_blue
red_cyan
red_electriccyan
red_green
green_magenta
yellow_blue
red_blueAnaglyph preset colors.

  • disabled - Disabled
    Forces usage of custom anaglyph colors.

  • red_blue - Red/Blue
    Classic red/blue anaglyph.

  • red_cyan - Red/Cyan
    Improved quality red/cyan anaglyph.

  • red_electriccyan - Red/Electric Cyan
    Alternate version of red/cyan

  • red_green - Red/Green

  • green_magenta - Green/Magenta

  • yellow_blue - Yellow/Blue
 
vb.anaglyph.rcolorinteger0x000000 through 0xFFFFFF0x00baffAnaglyph maximum-brightness color for right view.

 
vb.cpu_emulationenumfast
accurate
fastCPU emulation mode.

  • fast - Fast Mode
    Fast mode trades timing accuracy, cache emulation, and executing from hardware registers and RAM not intended for code use for performance.

  • accurate - Accurate Mode
    Increased timing accuracy, though not perfect, along with cache emulation, at the cost of decreased performance. Additionally, even the pipeline isn't correctly and fully emulated in this mode.
 
vb.default_colorinteger0x000000 through 0xFFFFFF0xF0F0F0Default maximum-brightness color to use in non-anaglyph 3D modes.

 
vb.disable_parallaxboolean0
1
0Disable parallax for BG and OBJ rendering.

 
vb.input.instant_read_hackboolean0
1
1Input latency reduction hack.

Reduces latency in some games by 20ms by returning the current pad state, rather than latched state, on serial port data reads. This hack may cause some homebrew software to malfunction, but it should be relatively safe for commercial official games.

 
vb.instant_display_hackboolean0
1
0Display latency reduction hack.

Reduces latency in games by displaying the framebuffer 20ms earlier. This hack has some potential of causing graphical glitches, so it is disabled by default.

 
vb.liprescaleinteger1 through 102Line Interlaced prescale.

 
vb.sidebyside.separationinteger0 through 10240Number of pixels to separate L/R views by.

This setting refers to pixels before vb.xscale(fs) scaling is taken into consideration. For example, a value of "100" here will result in a separation of 300 screen pixels if vb.xscale(fs) is set to "3".

 

Setting:Value Type:Possible Values:Default Value:Description:
vb.debugger.disfontsizeenumsmallDisassembly font size.

     
    vb.debugger.memcharencstring shift_jisCharacter encoding for the debugger's memory editor.

     
    vb.enableboolean0
    1
    1Enable (automatic) usage of this module.

     
    vb.forcemonoboolean0
    1
    0Force monophonic sound output.

     
    vb.pixshaderenumnone
    ipxnoty
    ipynotx
    ipsharper
    ipxnotysharper
    ipynotxsharper
    scale2x
    noneEnable specified OpenGL pixel shader.

    Obviously, this will only work with the OpenGL "video.driver" setting, and only on cards and OpenGL implementations that support pixel shaders, otherwise you will get a black screen, or Mednafen may display an error message when starting up. Bilinear interpolation is disabled with pixel shaders, and any interpolation, if present, will be noted in the description of each pixel shader.

    • none - None/Disabled

    • ipxnoty - Linear interpolation on X axis only.

    • ipynotx - Linear interpolation on Y axis only.

    • ipsharper - Sharper bilinear interpolation.

    • ipxnotysharper - Sharper version of "ipxnoty".

    • ipynotxsharper - Sharper version of "ipynotx".

    • scale2x - Scale2x
     
    vb.scanlinesinteger0 through 1000Enable scanlines with specified opacity.

    Opacity is specified in %; IE a value of "100" will give entirely black scanlines.

     
    vb.specialenumnone
    hq2x
    hq3x
    hq4x
    scale2x
    scale3x
    scale4x
    2xsai
    super2xsai
    supereagle
    nn2x
    nn3x
    nn4x
    nny2x
    nny3x
    nny4x
    noneEnable specified special video scaler.

    The destination rectangle is NOT altered by this setting, so if you have xscale and yscale set to "2", and try to use a 3x scaling filter like hq3x, the image is not going to look that great. The nearest-neighbor scalers are intended for use with bilinear interpolation enabled, at high resolutions(such as 1280x1024; nn2x(or nny2x) + bilinear interpolation + fullscreen stretching at this resolution looks quite nice).

    • none - None/Disabled

    • hq2x - hq2x

    • hq3x - hq3x

    • hq4x - hq4x

    • scale2x - scale2x

    • scale3x - scale3x

    • scale4x - scale4x

    • 2xsai - 2xSaI

    • super2xsai - Super 2xSaI

    • supereagle - Super Eagle

    • nn2x - Nearest-neighbor 2x

    • nn3x - Nearest-neighbor 3x

    • nn4x - Nearest-neighbor 4x

    • nny2x - Nearest-neighbor 2x, y axis only

    • nny3x - Nearest-neighbor 3x, y axis only

    • nny4x - Nearest-neighbor 4x, y axis only
     
    vb.stretchenum0
    full
    aspect
    0Stretch to fill screen.

    • 0 - Disabled

    • full - Full
      Full-screen stretch, disregarding aspect ratio.

    • aspect - Aspect Preserve
      Full-screen stretch as far as the aspect ratio(in this sense, the equivalent xscalefs == yscalefs) can be maintained.
     
    vb.tblurboolean0
    1
    0Enable video temporal blur(50/50 previous/current frame by default).

     
    vb.tblur.accumboolean0
    1
    0Accumulate color data rather than discarding it.

     
    vb.tblur.accum.amountreal0 through 10050Blur amount in accumulation mode, specified in percentage of accumulation buffer to mix with the current frame.

     
    vb.videoipboolean0
    1
    0Enable bilinear interpolation.

     
    vb.xresinteger64 through 65536800Full-screen horizontal resolution.

     
    vb.xscalereal0.01 through 2562.000000Scaling factor for the X axis.

     
    vb.xscalefsreal0.01 through 2562.000000Scaling factor for the X axis in fullscreen mode.

     
    vb.yresinteger64 through 65536600Full-screen vertical resolution.

     
    vb.yscalereal0.01 through 2562.000000Scaling factor for the Y axis.

     
    vb.yscalefsreal0.01 through 2562.000000Scaling factor for the Y axis in fullscreen mode.