Jolene has a great video where she explains the benefits of reducing or increasing gamma during gameplay. I'll summarise the main points but each point is demonstrated visually in the video.
• Lowering gamma will make circles visible later, which is usefwl for playing maps with high object density*. The effect of this is actually quite significant, and helps me a lot when I'm playing EZ.
* "Object density" is how many objects are visible on the screen at once. The higher the object density, the harder it is to read the patterns, which is why the EZ mod is actually very hard. The object density of a map depends on its AR, but also on how fast it is mapped. For example, a 250 bpm alternating map on AR 9 may be just as hard to read due to object density as a different 170 bpm map at AR8, simply because the first map has more circles per unit of time. Lowering gamma on maps like that may prove usefwl.
• The HD mod makes circles fade out before you have to click them. Increasing gamma will therefore make the circles stay visible for longer, which can be usefwl in some situations. But if you're playing a low-AR map on HD, increasing gamma will increase object density, so whether you want to increase or decrease gamma when using HD is usually a trade-off between these two things. Whether you want to increase or reduce gamma when playing EZHD depends on your individual skills, and whether you have most problems with the object density or the early fade-out.
Download
You can make the ahk script run on startup, so you don't have to start it every time you play osu. Open Run (Windows-key + R), and type "shell:startup", and copy a shortcut of the script, into that folder.
The default keyboard shortcuts work like this, but you can edit them in the script:
• numpadEnter + numpad8 (increase by 10)
• numpadEnter + numpad2 (decrease by 10)
• numpadEnter + numpad1 (set gamma to 0) (min)
• numpadEnter + numpad4 (set gamma to 50)
• numpadEnter + numpad5 (set gamma to 128) (this is default)
• numpadEnter + numpad6 (set gamma to 200)
• numpadEnter + numpad9 (set gamma 255) (max)
Summary of the effects of gamma on gameplay
• Increasing gamma will make circles visible sooner, because normally they fade in instead of being at full brightness immediately. This is very usefwl for playing high AR, for example with HR.• Lowering gamma will make circles visible later, which is usefwl for playing maps with high object density*. The effect of this is actually quite significant, and helps me a lot when I'm playing EZ.
* "Object density" is how many objects are visible on the screen at once. The higher the object density, the harder it is to read the patterns, which is why the EZ mod is actually very hard. The object density of a map depends on its AR, but also on how fast it is mapped. For example, a 250 bpm alternating map on AR 9 may be just as hard to read due to object density as a different 170 bpm map at AR8, simply because the first map has more circles per unit of time. Lowering gamma on maps like that may prove usefwl.
• The HD mod makes circles fade out before you have to click them. Increasing gamma will therefore make the circles stay visible for longer, which can be usefwl in some situations. But if you're playing a low-AR map on HD, increasing gamma will increase object density, so whether you want to increase or decrease gamma when using HD is usually a trade-off between these two things. Whether you want to increase or reduce gamma when playing EZHD depends on your individual skills, and whether you have most problems with the object density or the early fade-out.
Script for changing gamma with keyboard shortcuts
If you have to spend several seconds every time you want to change gamma while playing osu, then that may just be too annoying to bother with. Which is why I prefer using keyboard shortcuts that I can use with a single hand, to quickly change gamma between each map, or even between individual parts of a single map. osu!dev smoogipooo says that it is not considered cheating, by the way. You need to install AutoHotkey to make it work.Source code
#Persistent
OnExit, EOF
; ====================================================================================================
; Forum post about this script: t/739912
; DisplaySetBrightness (x) sets the gamma of monitor to x (min 0 and max 255). DisplayAdjustBrightness(x) increases (or decreases) gamma by x.
; Got the original script from here, and edited it slightly based on my needs: https://autohotkey.com/boards/viewtopic ... 760#p45760
; I use NumpadEnter because then I can adjust gamma without letting go of my mablet with my right hand. You can use whatever key you want.
; Here's a list of possible hotkeys: https://www.autohotkey.com/docs/Hotkeys.htm
NumpadEnter & Numpad1:: DisplaySetBrightness(0) ; sets the gamma to the min value (0).
NumpadEnter & Numpad4:: DisplaySetBrightness(50)
NumpadEnter & Numpad5:: DisplaySetBrightness(128) ; sets the gamma to the default value (128).
NumpadEnter & Numpad6:: DisplaySetBrightness(200)
NumpadEnter & Numpad9:: DisplaySetBrightness(255) ; sets the gamma to the max value (255).
NumpadEnter & Numpad8:: DisplayAdjustBrightness(10) ; increases gamma by 10.
NumpadEnter & Numpad2:: DisplayAdjustBrightness(-10) ; decreases gamma by 10.
; ====================================================================================================
DisplayAdjustBrightness(V = 0)
{
SB := (SB := DisplayGetBrightness() + V) > 255 ? 255 : SB < 0 ? 0 : SB
DisplaySetBrightness(SB)
}
DisplaySetBrightness(SB := 128)
{
loop % VarSetCapacity(GB, 1536) / 6
NumPut((N := (SB + 128) * (A_Index - 1)) > 65535 ? 65535 : N, GB, 2 * (A_Index - 1), "UShort")
DllCall("RtlMoveMemory", "Ptr", &GB + 512, "Ptr", &GB, "UPtr", 512, "Ptr")
, DllCall("RtlMoveMemory", "Ptr", &GB + 1024, "Ptr", &GB, "UPtr", 512, "Ptr")
return DllCall("gdi32.dll\SetDeviceGammaRamp", "Ptr", hDC := DllCall("user32.dll\GetDC", "Ptr", 0, "Ptr"), "Ptr", &GB), DllCall("user32.dll\ReleaseDC", "Ptr", 0, "Ptr", hDC)
}
DisplayGetBrightness(ByRef GB := "")
{
VarSetCapacity(GB, 1536, 0)
, DllCall("gdi32.dll\GetDeviceGammaRamp", "Ptr", hDC := DllCall("user32.dll\GetDC", "Ptr", 0, "Ptr"), "Ptr", &GB)
return NumGet(GB, 2, "UShort") - 128, DllCall("user32.dll\ReleaseDC", "Ptr", 0, "Ptr", hDC)
}
; ====================================================================================================
EOF:
DisplaySetBrightness(128) ; Sets gamma back to normal (128) when you exit the program
ExitApp
OnExit, EOF
; ====================================================================================================
; Forum post about this script: t/739912
; DisplaySetBrightness (x) sets the gamma of monitor to x (min 0 and max 255). DisplayAdjustBrightness(x) increases (or decreases) gamma by x.
; Got the original script from here, and edited it slightly based on my needs: https://autohotkey.com/boards/viewtopic ... 760#p45760
; I use NumpadEnter because then I can adjust gamma without letting go of my mablet with my right hand. You can use whatever key you want.
; Here's a list of possible hotkeys: https://www.autohotkey.com/docs/Hotkeys.htm
NumpadEnter & Numpad1:: DisplaySetBrightness(0) ; sets the gamma to the min value (0).
NumpadEnter & Numpad4:: DisplaySetBrightness(50)
NumpadEnter & Numpad5:: DisplaySetBrightness(128) ; sets the gamma to the default value (128).
NumpadEnter & Numpad6:: DisplaySetBrightness(200)
NumpadEnter & Numpad9:: DisplaySetBrightness(255) ; sets the gamma to the max value (255).
NumpadEnter & Numpad8:: DisplayAdjustBrightness(10) ; increases gamma by 10.
NumpadEnter & Numpad2:: DisplayAdjustBrightness(-10) ; decreases gamma by 10.
; ====================================================================================================
DisplayAdjustBrightness(V = 0)
{
SB := (SB := DisplayGetBrightness() + V) > 255 ? 255 : SB < 0 ? 0 : SB
DisplaySetBrightness(SB)
}
DisplaySetBrightness(SB := 128)
{
loop % VarSetCapacity(GB, 1536) / 6
NumPut((N := (SB + 128) * (A_Index - 1)) > 65535 ? 65535 : N, GB, 2 * (A_Index - 1), "UShort")
DllCall("RtlMoveMemory", "Ptr", &GB + 512, "Ptr", &GB, "UPtr", 512, "Ptr")
, DllCall("RtlMoveMemory", "Ptr", &GB + 1024, "Ptr", &GB, "UPtr", 512, "Ptr")
return DllCall("gdi32.dll\SetDeviceGammaRamp", "Ptr", hDC := DllCall("user32.dll\GetDC", "Ptr", 0, "Ptr"), "Ptr", &GB), DllCall("user32.dll\ReleaseDC", "Ptr", 0, "Ptr", hDC)
}
DisplayGetBrightness(ByRef GB := "")
{
VarSetCapacity(GB, 1536, 0)
, DllCall("gdi32.dll\GetDeviceGammaRamp", "Ptr", hDC := DllCall("user32.dll\GetDC", "Ptr", 0, "Ptr"), "Ptr", &GB)
return NumGet(GB, 2, "UShort") - 128, DllCall("user32.dll\ReleaseDC", "Ptr", 0, "Ptr", hDC)
}
; ====================================================================================================
EOF:
DisplaySetBrightness(128) ; Sets gamma back to normal (128) when you exit the program
ExitApp
You can make the ahk script run on startup, so you don't have to start it every time you play osu. Open Run (Windows-key + R), and type "shell:startup", and copy a shortcut of the script, into that folder.
The default keyboard shortcuts work like this, but you can edit them in the script:
• numpadEnter + numpad8 (increase by 10)
• numpadEnter + numpad2 (decrease by 10)
• numpadEnter + numpad1 (set gamma to 0) (min)
• numpadEnter + numpad4 (set gamma to 50)
• numpadEnter + numpad5 (set gamma to 128) (this is default)
• numpadEnter + numpad6 (set gamma to 200)
• numpadEnter + numpad9 (set gamma 255) (max)
