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"Fading system/Gamma control"
, by thechange
Includes an automatic screen fade in/out system as well as accurate gamma control - Utilizing Blitz' gamma control functions which only work in fullscreen.
Code
;,,,, ; Contents ;'''' ; ; <1> Overview ; <2.1> Fade system functions ; <2.2> Fade system usage example ; <3> Supplemental functions ; <4.1> Demo overview ; <4.2> Demo 1: Simple fading ; <4.3> Demo 2: Single buffered fading ; <4.4> Demo 3: Double buffered fading ; <4.5> Demo 4: Manual fading ; <4.6> Demo 5: Setting brightness ; <4.7> Demo 6: Colorizing ; <5> Fade system code ; ;,,,, ; <1> Overview ;'''' ; ; This independent gamma system encapsulates the Blitz functions ; SetGamma and UpdateGamma enabling you to: ; ; * automatically fade the screen in/out, ; * accurately control gamma manually: ; * lightness; making the screen relatively brighter ; which is also refered to as 'Gamma correction' in games, ; * darkness; making the screen relatively darker ; basically controlling the fullbright level or 'fullbrightness'. ; ; This is currently (Jan 2004) the fastest way of doing fullscreen fading ; using the 2D commandset in Blitz. The only limitation is that Blitz' ; gamma functions only work in fullscreen. ; ; TheChance <TheChange@yahoo.com> ; ;,,,, ; <2.1> Fade system functions ;'''' ; ; Fade_Init ; Mandatory initialization procedure. ; Fade_Exit ; Optional clean up procedure. ; ; Fade_Set ( Mode , Duration ) ; Start fade (1=In, 0=Out). ; Fade_In ( Duration ) ; Start fade in. ; Fade_Out ( Duration ) ; Start fade out. ; ; Notes: Duration defines total duration of fade in milliseconds. ; Which is 5,000 by default (5 seconds). ; Specifying a duration of 0 will cause an instant fade. ; ; Fade_Done% () ; Returns True when fade is done. ; Fade_Update ; Updates the fade. ; ; Notes: The smoothness of the Fade depends on the DefaultFadeDelay value ; which is set to 50ms by default. Decreasing this value will make ; the Fade smoother but put more strain on your system. Increasing ; this value will make the Fade jerk but relieve strain on Blitz. ; ; Examples with parameters: ; ; Fade_Set ( 1 , 1000 ) ; Fade in screen in 1 second, ; ; which is the equivalent of Fade_In ( 1000 ). ; ; Fade_Set ( 0 , 2500 ) ; Fade screen out in 2.5 seconds, ; ; which is the equivalent of Fade_Out ( 2500 ). ; ;,,,, ; <2.2> Fade system usage example ;'''' ; ; Graphics 640 , 480 , 0 , 1 ; <- Has to be fullscreen. ; ; Initialize ( game elements ) ; ; Fade_Init ; Mandatory. ; ; SetBuffer BackBuffer () ; Repeat ; ; ; Logic ; ; Update ( game elements ) ; ; If ( game requires fade out ) Then Fade_Out duration ; If ( game requires fade in ) Then Fade_In duration ; If ( game requires any fade ) Then Fade_Set mode , duration ; ; Fade_Update ; ; ; Visual ; ; Display ( game elements ) ; ; Flip ; ; Until ( game finished ) ; ; Fade_Exit ; Optional. ; End ; ;,,,, ; <3> Supplemental functions ;'''' ; ; Gamma_Set ( Intensity# , [ Red# ] , [ Green# ] , [ Blue# ] ) ; ; Easy, fast, flexible, accurate and instant gamma control. ; ; Intensity# ; Gamma level [0..255] ; 0 = darkest (black) ; 1 = fullbright (normal) ; 255 = brightest (white) ; ; Red#, Green#, Blue# ; Color level [0..1] ; 0 = black ; 1 = fullbright ; ; Examples: ; ; Gamma_Set ( 1 ) ; Set normal brightness (fullbright). ; Gamma_Set ( 0.5 ) ; Set half brightness. ; Gamma_Set ( 0 ) ; Black screen :P ; Gamma_Set ( 255 ) ; White screen :P ; Gamma_Set ( 1 , 0 , 0 , 1 ) ; Colorize the screen blue. ; Gamma_Set ( 1 , 1 , 0.5 , 0 ) ; Colorize the screen orange. ; Gamma_Set ( 128 , 0 , 1 , 0 ) ; Superbright green screen. ; ;,,,, ; <4.1> Demo overview ;'''' ; ; Included are some demos to display all aspects of the system. ; ; Demo 1. Shows most direct usage of the fade system, ; without buffering or screen redraws, ; using the Fade_Set command. ; ; Demo 2. Displays the same as the first demo, ; but with singularly buffered screen redraws. ; ; Demo 3. Makes use of double buffering and screen redraws, ; using the fade system through the Fade_In and Fade_Out commands. ; ; Demo 4. Displays how you can fade the screen manually using Gamma_Set (). ; Demo 5. Sets lightness and darkness levels using the Gamma_Set command. ; Demo 6. Shows how to colorize the screen using Gamma_Set (). ; ; Each demo is labelled (.Demo1, .Demo2, etc) ; so you can try each one out right here, right now, using a Goto :) Goto Demo1 ;,,,, ; <4.2> Demo 1: Simple fading ;'''' ; ; Displays: ; * how to fade in/out using Fade_Set, ; * you can use the system without having to redrawing the screen, ; changes are instant! :) ; .Demo1 ; Draw box with color gradient; horizontally: colors, vertically: intensity (black->normal) Function gradbox_black(x1,y1,x2,y2,r1,g1,b1,r2,g2,b2) incr#=(r2-r1)/(x2-x1) ; scale pixel range to color range incg#=(g2-g1)/(x2-x1) incb#=(b2-b1)/(x2-x1) For x=x1 To x2 For y=y1 To y2 intensity = (y-y1)*255/(y2-y1) ; scale pixel range to color brightness r = intensity * r1 / 255 ; scale intensity to color range g = intensity * g1 / 255 b = intensity * b1 / 255 Color r,g,b Plot x , y Next r1=r1+incr g1=g1+incg b1=b1+incb Next End Function ; Draw box with color gradient; horizontally: colors, vertically: intensity (normal->white) Function gradbox_white(x1,y1,x2,y2,r1,g1,b1,r2,g2,b2) incr#=(r2-r1)/(x2-x1) ; scale pixel range to color range incg#=(g2-g1)/(x2-x1) incb#=(b2-b1)/(x2-x1) For x=x1 To x2 For y=y1 To y2 intensity = (y2-y)*255/(y2-y1) ; scale inversed pixel range to color brightness r = 255-intensity * (255-r1) / 255 ; scale inversed intensity to inversed color g = 255-intensity * (255-g1) / 255 b = 255-intensity * (255-b1) / 255 Color r,g,b Plot x , y Next r1=r1+incr g1=g1+incg b1=b1+incb Next End Function AppTitle "Simple fading" SeedRnd MilliSecs () Graphics 640 , 480 , 0 , 1 ; <- Has to be fullscreen. SetFont LoadFont ( "Arial" , 11 , True ) ; Instantly load and set font. Fade_Init ; Initialize fade system. Screen_IsVisible = True ; Using a flag to keep track of fade. SetBuffer FrontBuffer () ; Note: Works with double buffering too. ; Draw some stuff on the screen, some nice stuff :) gradbox_black 0, 0, 50, 50 , 255, 0, 0 , 255,255, 0 gradbox_black 50, 0,100, 50 , 255,255, 0 , 0,255, 0 gradbox_black 100, 0,150, 50 , 0,255, 0 , 0,255,255 gradbox_black 150, 0,200, 50 , 0,255,255 , 0, 0,255 gradbox_black 200, 0,250, 50 , 0, 0,255 , 255, 0,255 gradbox_black 250, 0,300, 50 , 255, 0,255 , 255, 0, 0 ; This is actually very much like PSP's color table. gradbox_white 0, 50, 50,100 , 255, 0, 0 , 255,255, 0 gradbox_white 50, 50,100,100 , 255,255, 0 , 0,255, 0 gradbox_white 100, 50,150,100 , 0,255, 0 , 0,255,255 gradbox_white 150, 50,200,100 , 0,255,255 , 0, 0,255 gradbox_white 200, 50,250,100 , 0, 0,255 , 255, 0,255 gradbox_white 250, 50,300,100 , 255, 0,255 , 255, 0, 0 ; Finishing with a message. Color 255 , 255 , 255 Text 0 , 200 , "Press <space> to toggle fade in/out" ; The screen will not be redrawn. Repeat If KeyHit ( 57 ) ; Toggle visibility. Screen_IsVisible = Not Screen_IsVisible ; And fade towards the new setting. Fade_Set Screen_IsVisible , 1000 ; Fade in 1 second. End If ; Updating the fade constantly for a smooth fade. Fade_Update ; Press ESC to quit. Until KeyHit ( 1 ) End ;,,,, ; <4.3> Demo 2: Single buffered fading ;'''' ; ; Displays: ; * how to fade in/out using Fade_Set, ; * fading while redrawing the screen using single buffering. ; .Demo2 AppTitle "Single buffered fading" SeedRnd MilliSecs () Screen_SizeX = 640 Screen_SizeY = 480 Graphics Screen_SizeX , Screen_SizeY , 0 , 1 SetFont LoadFont ( "Arial" , 11 , True ) Fade_Init Screen_IsVisible = True SetBuffer FrontBuffer () ; Note: Works with double buffering too. Repeat ;-- Logic. If KeyHit ( 57 ) Screen_IsVisible = Not Screen_IsVisible Fade_Set Screen_IsVisible End If Fade_Update ;-- Visual. ; Add random square to the screen. Color Rand ( 0 , 255 ) , Rand ( 0 , 255 ) , Rand ( 0 , 255 ) Rect Rand ( -Screen_SizeX , Screen_SizeX*2-1 ) , Rand ( -Screen_SizeY , Screen_SizeY*2-1 ) , Rand ( Screen_SizeX ) , Rand ( Screen_SizeY ) , True ; Info and status messages. Color 0 , 0 , 0 Rect 0 , 0 , Screen_SizeX/2 , 10 , True Color 255 , 255 , 255 Text 0 , 0 , "Press <space> to toggle fade in/out - Fade done: " + Mid ( "FalseTrue" , Fade_Done () * 5 + 1 , 5 ) ; Using single buffering. VWait ; Not flipping, just waiting Until KeyHit ( 1 ) End ;,,,, ; <4.4> Demo 3: Double buffered fading ;'''' ; ; Displays: ; * how to fade in/out using Fade_In and Fade_Out, ; * fading while redrawing the screen using double buffering. ; .Demo3 ; Uses an object collection of thingies to put on the screen. Type Thingy Field PosX# Field PosY# Field SpeedX# Field SpeedY# Field Color ; 0..16777215 combined RGB value. Field SizeX Field SizeY Field Shape ; 0 for Oval, 1 for Square. End Type AppTitle "Double buffered fading" SeedRnd MilliSecs () Screen_SizeX = 640 Screen_SizeY = 480 Graphics Screen_SizeX , Screen_SizeY , 0 , 1 Fade_Init Screen_IsVisible = True ; Make some thingies to be moved around the screen. For Count = 1 To 100 Pointer.Thingy = New Thingy Pointer\PosX = Rand ( 0 , Screen_SizeX-1 ) Pointer\PosY = Rand ( 0 , Screen_SizeY-1 ) Pointer\SpeedX = Rnd ( -1 , 1 ) Pointer\SpeedY = Rnd ( -1 , 1 ) Pointer\Color = Rand ( 0 , 16777215 ) Pointer\SizeX = Rand ( 1 , Screen_SizeX/10 ) Pointer\SizeY = Rand ( 1 , Screen_SizeY/10 ) Pointer\Shape = Rand ( 0 , 1 ) Next SetBuffer BackBuffer () ; Using double buffering. Repeat ;-- Logic. ; Press space to fade in/out. If KeyHit ( 57 ) If Screen_IsVisible Fade_Out 2000 Else Fade_In 2000 End If Screen_IsVisible = Not Screen_IsVisible End If ; Move thingies. For Pointer = Each Thingy Pointer\PosX = Pointer\PosX + Pointer\SpeedX Pointer\PosY = Pointer\PosY + Pointer\SpeedY If Pointer\PosX < -Pointer\SizeX Then Pointer\PosX = Pointer\PosX + Screen_SizeX + Pointer\SizeX If Pointer\PosY < -Pointer\SizeY Then Pointer\PosY = Pointer\PosY + Screen_SizeY + Pointer\SizeY If Pointer\PosX >= Screen_SizeX Then Pointer\PosX = Pointer\PosX - Screen_SizeX - Pointer\SizeX If Pointer\PosY >= Screen_SizeY Then Pointer\PosY = Pointer\PosY - Screen_SizeY - Pointer\SizeY Next ; Measure Frames Per Second. If MilliSecs () - FrameTime >= 1000 FrameTime = MilliSecs () FPS = Frames Frames = 0 End If Frames = Frames + 1 Fade_Update ;-- Visual ; Displaying the thingies. For Pointer = Each Thingy ; Fill shape with specified color. Color 0 , 0 , Pointer\Color If Pointer\Shape Rect Pointer\PosX , Pointer\PosY , Pointer\SizeX , Pointer\SizeY Else Oval Pointer\PosX , Pointer\PosY , Pointer\SizeX , Pointer\SizeY End If ; Outline shape with different (inverted) color. Color 0 , 0 , -Pointer\Color If Pointer\Shape Rect Pointer\PosX , Pointer\PosY , Pointer\SizeX , Pointer\SizeY , False Else Oval Pointer\PosX , Pointer\PosY , Pointer\SizeX , Pointer\SizeY , False End If Next Color 255 , 255 , 255 Text 0 , 0 , "Press <space> to toggle fade in/out" Text 0 , 10 , "Fade done: " + Mid ( "FalseTrue" , Fade_Done () * 5 + 1 , 5 ) Text 0 , 20 , "FPS: " + FPS ; Double buffering so flip the screen. ; But not synchronizing with the monitor to see the actual FPS speed hit. Flip False Cls Until KeyHit ( 1 ) End ;,,,, ; <4.5> Demo 4: Manual fading ;'''' ; ; Displays how you can manually set the darkness of the screen ; feeding the result of a calculation using a percentage ; to the Gamma_Set function. ; .Demo4 AppTitle "Manual fading" SeedRnd MilliSecs () Graphics 640 , 480 , 0 , 1 ClsColor 255 , 255 , 255 ; Fullbright background (kadang!). Value = 50 ; Percentage of 'fullbrightness', where 100% is normal brightness. SetBuffer BackBuffer () Repeat ; Use left/right to adjust fullbright percentage. If KeyDown ( 203 ) Then Value = Value - 1 If KeyDown ( 205 ) Then Value = Value + 1 ; Limit percentage to (0..100). If Value < 0 Then Value = 0 If Value >= 100 Then Value = 100 ; Display percentage info. Color 255 , 0 , 0 Rect 0 , 0 , 100 , 40 Color 0 , 0 , 0 Rect 0 , 0 , 100 , 40 , False Line Value , 0 , Value , 39 Text 50 , 20 , Value + "%" , True , True ; Adjust fullbright gamma, in range of (0..1). Gamma# = Float Value / 100 Gamma_Set Gamma Flip Cls Until KeyHit ( 1 ) End ;,,,, ; <4.6> Demo 5: Setting brightness ;'''' ; ; Displays how to set both darkness and lightness (gamma correction/'fullbrightness') ; of the screen using a gamma value directly passed to the Gamma_Set function. ; .Demo5 AppTitle "Setting brightness" SeedRnd MilliSecs () Screen_SizeX = 640 Screen_SizeY = 480 Graphics Screen_SizeX , Screen_SizeY , 0 , 1 SetFont LoadFont ( "Arial" , 25 , True ) ; Create a background of grey vertical bars. Background = CreateImage ( 640 , 480 ) SetBuffer ImageBuffer ( Background ) For Color = 0 To 255 Color Color , Color , Color Offset = Color * Screen_SizeX / 255 ; Scale color range to horizontal screen dimension. Rect Offset , 0 , 640-Offset , 480 , True Next Gamma# = 1 SetBuffer BackBuffer () Repeat ; Draw the grey bars. DrawBlock Background , 0 , 0 ; Use Left/Right to exponentially increase/decrease gamma level. If KeyDown ( 203 ) Then Gamma = Gamma / 1.1 If KeyDown ( 205 ) Then Gamma = Gamma * 1.1 ; Keep gamma in manageable ranges. If Gamma > 255 Then Gamma = 255 If Gamma <= 0 Then Gamma = 0.0001 ; Display current gamma level. Color 0 , 0 , 0 Text Screen_SizeX/2 , Screen_SizeY/2 , "Gamma: " + Gamma , True , True ; Set current gamma level. Gamma_Set Gamma Flip Cls Until KeyHit ( 1 ) End ;,,,, ; <4.7> Demo 6: Colorizing ;'''' ; ; Displays how to colorize the screen using Gamma_Set. ; .Demo6 AppTitle "Colorizing" SeedRnd MilliSecs () Screen_SizeX = 640 Screen_SizeY = 480 ChangeColor_Delay = 1000 ; Change colors each second. Graphics Screen_SizeX , Screen_SizeY , 0 , 1 Fade_Init SetBuffer FrontBuffer () Repeat ;-- Logic. ; Change random gamma color at a regular interval. If MilliSecs () - ChangeColor_Time >= ChangeColor_Delay ChangeColor_Time = MilliSecs () ; Brightness 1 (fullbright) with random colors (red, green, blue). Gamma_Set 1 , Rnd ( 0 , 1 ) , Rnd ( 0 , 1 ) , Rnd ( 0 , 1 ) End If ;-- Visual. ; Draw random boxes. Color Rand ( 0 , 255 ) , Rand ( 0 , 255 ) , Rand ( 0 , 255 ) Rect Rand ( -Screen_SizeX , Screen_SizeX*2-1 ) , Rand ( -Screen_SizeY , Screen_SizeY*2-1 ) , Rand ( Screen_SizeX/10 ) , Rand ( Screen_SizeY/10 ) , True Until KeyHit ( 1 ) End ;,,,, ; <5> Fade system ;'''' ; Constants. Const GammaFade_DefaultDuration = 5000 ; Ms. Const GammaFade_DefaultFadeDelay = 50 ; Ms. ; Structures. Type GammaFade_Base Field Done ; Fading runs if True. Field Started ; When fade was started. Field Duration ; Time for entire fade to take. Field Direction ; Fade direction (In = 1, Out = 0). Field LastFade ; Time of previous fade update. Field FadeDelay ; Time between each fade update. End Type ; Root structure. Global GammaFade_.GammaFade_Base ; Methods. ; Reset fade system. Function Fade_Init () If GammaFade_ = Null Then GammaFade_ = New GammaFade_Base GammaFade_\Done = True GammaFade_\Duration = GammaFade_DefaultDuration GammaFade_\FadeDelay = GammaFade_DefaultFadeDelay End Function ; Clean up remains. Function Fade_Exit () Delete GammaFade_ End Function ; Initiate fade. Function Fade_Set ( Fade_Mode , Fade_Duration = GammaFade_DefaultDuration ) Local Level ; Instant fade. If Fade_Duration = 0 ; Warp to final destination. If Fade_Mode For Level = 0 To 255 SetGamma Level , Level , Level , Level , Level , Level Next Else For Level = 0 To 255 SetGamma Level , Level , Level , 0 , 0 , 0 Next End If UpdateGamma ; Fade done. GammaFade_\Done = True ; Gradual fade. Else ; Remember gradual fade direction (in/out). GammaFade_\Direction = Fade_Mode ; Remember duration of fade. GammaFade_\Duration = Fade_Duration ; Remember current time (start time). GammaFade_\Started = MilliSecs () ; Run fade. GammaFade_\Done = False End If End Function ; Initiate fade in. Function Fade_In ( Duration = GammaFade_DefaultDuration ) Fade_Set True , Duration End Function ; Initiate fade out. Function Fade_Out ( Duration = GammaFade_DefaultDuration ) Fade_Set False , Duration End Function ; Check if fade is done. Function Fade_Done% () Return GammaFade_\Done End Function ; Update the fade system. Function Fade_Update () Local Time_Elapsed Local Gamma_Level Local Target_Level Local MilliSecs ; Still fading. If Not GammaFade_\Done ; Check the time. MilliSecs = MilliSecs () ; Time to update the fade. If MilliSecs - GammaFade_\LastFade >= GammaFade_\FadeDelay ; Remember the time. GammaFade_\LastFade = MilliSecs ; Time since start. Time_Elapsed = MilliSecs - GammaFade_\Started ; Fade's duration has elapsed. If Time_Elapsed >= GammaFade_\Duration ; Finish gamma table and clean up. Fade_Set GammaFade_\Direction , 0 ; Still fading. Else ; Set gamma levels depending on fade direction. If GammaFade_\Direction For Gamma_Level = 0 To 255 Target_Level = Time_Elapsed * Gamma_Level / GammaFade_\Duration SetGamma Gamma_Level , Gamma_Level , Gamma_Level , Target_Level , Target_Level , Target_Level Next Else For Gamma_Level = 0 To 255 Target_Level = Gamma_Level - Time_Elapsed * Gamma_Level / GammaFade_\Duration SetGamma Gamma_Level , Gamma_Level , Gamma_Level , Target_Level , Target_Level , Target_Level Next End If UpdateGamma End If End If End If End Function ; (Independent) Gamma control. Function Gamma_Set ( Brightness# = 1 , Red# = 1 , Green# = 1 , Blue# = 1 ) Local Gamma_Level Local Target_Level For Gamma_Level = 0 To 255 ; Use accurate exponential ranges (0..1, 1..255). If Brightness > 1 Target_Level = (Gamma_Level+1) * (Brightness/(Gamma_Level+1)+1) - 1 Else Target_Level = Gamma_Level * Brightness End If ; Ensure compatibility with BlitzPlus. If Target_Level < 0 Then Target_Level = 0 If Target_Level > 255 Then Target_Level = 255 ; Apply changes. SetGamma Gamma_Level , Gamma_Level , Gamma_Level , Target_Level * Red , Target_Level * Green , Target_Level * Blue Next UpdateGamma End Function ;-->
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Code software created by Krylar's Kreations
