Image rotation? - BlitzCoder.net

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Socoder -> Blitz -> Image rotation?
Tue, 30 Nov 2010, 10:57
spinal	I am trying to rotate an image (yes I know there is a rotate image function, I'm not going to use it). Anyway, the simple way is to do the following -- ; Rotate image... Graphics 640,480,0,2 pic = CreateImage(120,12) SetBuffer ImageBuffer(pic) Color 255,0,0 Rect 0,0,120,12,1 Color 0,0,255 Text 0,0,"OOOOOOOOOOOOOOOOOOOOOOOOOO" angle = 0 While Not KeyHit(1) SetBuffer FrontBuffer() Cls angle=angle+1 For x=-60 To 60 For y = -6 To 6 SetBuffer ImageBuffer(pic) GetColor(x+60,y+6) rx = x * Cos(angle) - y * Sin(angle) ry = x * Sin(angle) + y * Cos(angle) SetBuffer FrontBuffer() Plot rx + 200, ry + 200 Next Next Wend End --v However, it does leave gaps in the output image. I read somewhere that image rotation should be done backwards, as in, cycle through the output image and work out which pixel should be there, or something like that. But I have yet to find any info on how to do this. Does anyone know how this is done? -=-=- Check out my excellent homepage!
Wed, 01 Dec 2010, 02:46
Jayenkai	It's quite awkward to think of this backwards, when you're working with pixels of a rotated rectangle. Instead, simplify it. You need to fill surrounding pixels of each pixel, so just do that. Find each rx/ry, then go backwards for each pixel that's around it. ; Rotate image... Graphics 1024,768,0,2 Graphics 320,240,0,3 SetBuffer BackBuffer() pic = CreateImage(120,12) SetBuffer ImageBuffer(pic) Color 255,0,0 Rect 0,0,120,12,1 Color 0,0,255 Text 0,0,"ABCDEFGHIJKLMNOPQRSTUVWXYZ" angle = 0 While Not KeyHit(1) SetBuffer BackBuffer() Cls angle=angle+1 For x=-60 To 60 For y = -6 To 6 rx = x * Cos(angle) - y * Sin(angle) ry = x * Sin(angle) + y * Cos(angle) ; For each pixel, find neighbour pixels of rotated version, then work back to find original pixels in roughly those points.. For ex=rx-1 To rx+1 For ey=ry-1 To ry+1 ; Unrotate unrotatex=Float(ex) * Cos(-angle) - Float(ey) * Sin(-angle) unrotatey=Float(ex) * Sin(-angle) + Float(ey) * Cos(-angle) ; Find colour at that point SetBuffer ImageBuffer(pic) GetColor(unrotatex+60,unrotatey+6) SetBuffer BackBuffer() ; Slap it back in.. Plot ex + 100, ey + 100 Next Next Next Next Flip Wend End --v -=-=- ''Load, Next List!''
Wed, 01 Dec 2010, 09:22
Andy_A	A quick and dirty way to fill in the gaps is to plot a 2x2 rect instead of a single pixel. The drawback is that your image may be slightly distorted due to the way the rects overlap. ; Rotate image... Graphics 640,480,0,2 pic = CreateImage(120,12) SetBuffer ImageBuffer(pic) Color 255,0,0 Rect 0,0,120,12,1 Color 0,0,255 Text 0,0,"OOOOOOOOOOOOOOOOOOOOOOOOOO" angle = 0 While Not KeyHit(1) SetBuffer FrontBuffer() Cls angle=angle+1 For x=-60 To 60 For y = -6 To 6 SetBuffer ImageBuffer(pic) GetColor(x+60,y+6) rx = x * Cos(angle) - y * Sin(angle) ry = x * Sin(angle) + y * Cos(angle) SetBuffer FrontBuffer() Rect rx + 200, ry + 200, 2, 2, True ;will cause some distortion in final image Next Next Wend End --v
Wed, 01 Dec 2010, 12:34
spinal	OK, I tweaked Jay's code a little, removed the initial rotation and instead worked completely backwards. I assume though, that there is a simple way to find the min and max x and y values from checking the rotation of the image corners first though, I just guessed Graphics 640,480,0,2 Graphics 320,240,0,3 SetBuffer BackBuffer() pic = CreateImage(120,12) SetBuffer ImageBuffer(pic) Color 255,0,0 Rect 0,0,120,12,1 Color 0,0,255 Text 0,0,"ABCDEFGHIJKLMNO" angle = 0 While Not KeyHit(1) SetBuffer BackBuffer() Cls angle=angle+1 If angle > 360 Then angle = angle - 360 Color 255,255,255 Rect 40,40, 120, 120,0 For ex = 41 To 158 For ey = 41 To 158 ; Unrotate unrotatex=(ex-100) * Cos(-angle) - (ey-100) * Sin(-angle) unrotatey=(ex-100) * Sin(-angle) + (ey-100) * Cos(-angle) If unrotatex > -60 And unrotatex < 60 And unrotatey > -6 And unrotatey < 6 Then ; Find colour at that point SetBuffer ImageBuffer(pic) GetColor(unrotatex+60,unrotatey+6) SetBuffer BackBuffer() ; Slap it back in.. Plot ex, ey End If Next Next Flip Wend End --v -=-=- Check out my excellent homepage!
Wed, 15 Dec 2010, 16:51
Teasy	That looks neat ^^ For finding the maximum image rotation corners, I think you're looking for something like this, Spinal ; calculate maximum rotation radius (maximum distance from hotspot) Function GetMaxRad( w,h , rx,ry ) Local w2 = w / 2 Local h2 = h / 2 Local mx = Abs( rx - w2 ) + w2 Local my = Abs( ry - h2 ) + h2 Return VectorDistance( mx,my ) End Function --v To see it in action, in a slightly modified program: Const sw = 400 Const sh = 300 Graphics sw,sh , 0,3 SetFont LoadFont( "FixedSys" ) ; image dimensions (width, height) Const w = 120 - 3 Const h = 12 + 2 ; image hue Const r = 0 Const g = 192 Const b = 0 Global pic = CreateImage(w,h) SetBuffer ImageBuffer(pic) Color r,g,b Rect 0,0 , w,h , 1 TextOutLine 2,0,"OUT OF THE BOX" , 0,0 , 0,0,0 , r/2,g/2,b/2 Local raster_overlay = CreateImage( sw,sh ) MaskImage raster_overlay , 255,255,255 Color 255,255,255 SetBuffer ImageBuffer( raster_overlay ) Local y For y = 0 To sh-1 Step 2 Rect 0,y , sw,1 Next Local angle# = 0 Local speed# = 0 ; calculate maximum rotation radius (maximum distance from hotspot) Local rr = GetMaxRad( w,h , w/2,h/2 ) DebugLog "Radius: "+rr ; drawing offset (rotation hotspot is center) Local dx = sw/2 Local dy = sh/2 Local frames,fps Local ms,lastsec SetBuffer BackBuffer() ClsColor 0,64,0 SeedRnd MilliSecs() While Not KeyHit(1) Cls angle = angle + speed If angle < 0 Then angle = angle + 360 If angle >= 360 Then angle = angle - 360 speed = speed + Rnd( -.125 , .125 ) If speed < -2 Then speed = -2 If speed >= 2 Then speed = 2 Color 0,72,0 Circle dx,dy , rr2 Local ca# = Cos(-angle) Local sa# = Sin(-angle) Local ex,ey For ex = -rr To rr For ey = -rr To rr ; Unrotate Local unrotatex = ex ca - ey * sa Local unrotatey = ex * sa + ey * ca If unrotatex>-w/2 And unrotatex<w/2 And unrotatey>-h/2 And unrotatey<h/2 ; Find colour at that point RGB = ReadPixel( unrotatex+w/2,unrotatey+h/2 , ImageBuffer(pic) ) ; Slap it back in.. Color 0,0,RGB Plot dx+ex,dy+ey End If Next Next frames = frames + 1 ms = MilliSecs() If ms-lastsec >= 1000 lastsec = ms fps = frames frames = 0 End If TextOutLine 0,0 , fps , 0,0 , r,g,b , r/2,g/2,b/2 TileImage raster_overlay , 0,0 Flip False Delay 1 Wend End ; calculate maximum rotation radius (maximum distance from hotspot) Function GetMaxRad( w,h , rx,ry ) Local w2 = w / 2 Local h2 = h / 2 Local mx = Abs( rx - w2 ) + w2 Local my = Abs( ry - h2 ) + h2 Return VectorDistance( mx,my ) End Function ; polar & cartesian coordinate conversion routines Function VectorX# ( Distance# , Angle# ) Return Sin ( Angle ) * Distance End Function Function VectorY# ( Distance# , Angle# ) Return Sin ( Angle - 90 ) * Distance End Function Function VectorDistance# ( X# , Y# ) Return Sqr ( X * X + Y * Y ) End Function Function VectorAngle# ( X# , Y# ) Return 180 - ATan2 ( X , Y ) End Function Function LineBox( x1,y1 , x2,y2 ) Local dx = x2-x1 Local dy = y2-y1 Rect x1,y1 , dx,1 Rect x1,y2 , dx,1 Rect x1,y1 , 1,dy Rect x2,y1 , 1,dy End Function Function Circle( cx,cy , rad , fill=True ) Oval cx-rad/2,cy-rad/2 , rad,rad , fill End Function ; Like Text() only with 3x3 outline, for example to make white text visible on white background Function TextOutLine( PosX%,PosY% , Message$ , CenterX=False,CenterY=False , InR=255,InG=255,InB=255 , OutR=0,OutG=0,OutB=0 , Separation=1 ) ; 09 sep 2007: ; - swapped inner/outer color (inner color is now white, outer is black) Local X% Local Y% Color OutR,OutG,OutB ; CenterX: 0 = Left justify, 1 = Center, 2 = Right justify If CenterX = 2 PosX = PosX - StringWidth( Message ) CenterX = False EndIf ; CenterY: 0 = Top justify, 1 = Center, 2 = Bottom justify If CenterY = 2 PosY = PosY - StringHeight( Message ) CenterY = False EndIf For X = -1 To 1 For Y = -1 To 1 Text PosX + X * Separation , PosY + Y * Separation , Message , CenterX , CenterY Next Next Color InR,InG,InB Text PosX,PosY , Message , CenterX,CenterY End Function --v There is also room for more optimization ^^
Sat, 18 Dec 2010, 13:39
dna	Jay, In your code you use : Graphics 1024,768,0,2 Graphics 320,240,0,3 What does that do? Why is that in there twice? @Teasy: That's real smoothe. I can see where BB is slow when doing this. Does BMax make a difference as far as the speed of the rot? -=-=- DNA
Sat, 18 Dec 2010, 15:06
Jayenkai	,2 says "Make the window THIS big" ,3 says "Make this a scalable window." With a scalable window, you can Maximise it if you wish, but everything ends up looking a bit blurry and stretchy. It's a nice thing to have, but ,2 will always be clearer. However.. ,3 doesn't set the window's default size. So, by setting a LARGE ,2 (and making the window be 1024x768) and THEN setting a smaller ,3, you end up with the 320x240 graphics being rescaled up to the 1024x768 size. Basically, whereas we're drawing things to only a 320x240 area, they're actually being displayed 3 times bigger on the screen. Otherwise, you'd be looking at a teensy tiny window! -=-=- ''Load, Next List!''
Sat, 18 Dec 2010, 16:03
CodersRule	I never knew you could do that. I always wondered how to make a resizable window that big by default.
Sat, 25 Dec 2010, 06:31
Teasy	dna: if you optimize the code way more, it should be smooth and superfast in blitz2d even i still have some of blitzcoder's code laying around from optimization/math wizards ^^ which does exactly that! i am not familiar with blitzmax' graphics interface/library (opengl) benchmarks, but i imagine that it usually depends on (the wishes of) the coder whether something is fast or not taking into account that blitzmax is more capable, flexible and faster in itself, it may be fairly easy to get fast results in it jayenkai: that's a nice trick i usually use some dll calls to pull that off ^^ ( with userlibs it's a snap really ) codersrule: particularly the functions from the user32.dll can make the entire blitz window: - stretch to overlap the entire screen, - remove the caption and borders, - and stay on top. so basically a 'fake fullscreen' here's the code i use to do that: GraphicsWindow 640,480 , 0,4 --v and here's the "library" (interface) i'm using: ;------------------------------------------------------------------------------- ; * Window Handling ;------------------------------------------------------------------------------- ; Created by Teasy <TheChange@yahoo.com> ; With divine help from EPS, Yan and Rufus Serano ;------------------------------------------------------------------------------- ; Use Windows' native system functions to change a window's properties, ; such as its dimensions, state and visual make-up. ;------------------------------------------------------------------------------- ; 22 Dec 2010 ; - Changed layout of code ; - Added GraphicsWindowWidth and GraphicsWindowHeight ; - Uses "AppHWND" for safer window access ; - Added GraphicsWindow() which wraps Graphics() with a new mode (4) ; - Mode 4 turns the window into a fake fullscreen (scaled) ;------------------------------------------------------------------------------- ;, ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;,,, , , ;;;,d%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&b. ;,d&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%b. ;&%&%&%&' ;%&%&%&% Window state ;&%&%&%&, ;'V&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%P` ;;;'V%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&P` ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;:::·· · · ;' Const SW_HIDE = 0 Const SW_SHOWNORMAL = 1 Const SW_NORMAL = 1 Const SW_SHOWMINIMIZED = 2 Const SW_SHOWMAXIMIZED = 3 Const SW_MAXIMIZE = 3 Const SW_SHOWNOACTIVATE = 4 Const SW_SHOW = 5 Const SW_MINIMIZE = 6 Const SW_SHOWMINNOACTIVE = 7 Const SW_SHOWNA = 8 Const SW_RESTORE = 9 Const SW_SHOWDEFAULT = 10 Const SW_MAX = 11 ;------------------------------------------------------------------------------- ; Change the active window, e.g. Blitz Function ShowWindow( message = SW_NORMAL ) Local window_handle = api_GetActiveWindow() api_ShowWindow( window_handle , message ) End Function Function ShowWindow_Demo() Graphics 512,384 , 0,3 Print "untouched" : WaitKey : Cls ShowWindow SW_MAXIMIZE Print "maximized" : WaitKey : Cls ShowWindow SW_RESTORE Print "restored" : WaitKey : Cls End End Function ;------------------------------------------------------------------------------- ; * Active window functions ;------------------------------------------------------------------------------- ; User32.decls: ; .lib "USER32.DLL" ; API_ShowWindow( hWnd% , nCmdShow% ) : "ShowWindow" ; API_GetActiveWindow%() : "GetActiveWindow" ;------------------------------------------------------------------------------- Function MaximizeActiveWindow() api_ShowWindow api_GetActiveWindow() , 3 End Function Function MinimizeActiveWindow() api_ShowWindow api_GetActiveWindow() , 6 End Function Function RestoreActiveWindow() api_ShowWindow api_GetActiveWindow() , 9 End Function ;, ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;,,, , , ;;;,d%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&b. ;,d&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%b. ;&%&%&%&' ;%&%&%&% Window dimensions ;&%&%&%&, ;'V&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%P` ;;;'V%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&P` ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;:::·· · · ;' Type struct_RECT Field Left Field Top Field Right Field Bottom End Type Global struct_RECT.struct_RECT = New struct_RECT ;------------------------------------------------------------------------------- ; userlibs: ; user32.decls ; .lib "user32.dll" ; api_GetDesktopWindow%() : "GetDesktopWindow" ; api_GetWindowRect%( hwnd% , lpRect* ) : "GetWindowRect" ;------------------------------------------------------------------------------- Function ActiveWindowWidth() api_GetWindowRect api_GetActiveWindow() , struct_RECT Return struct_RECT\Right - struct_RECT\Left End Function Function ActiveWindowHeight() api_GetWindowRect api_GetActiveWindow() , struct_RECT Return struct_RECT\Bottom - struct_RECT\Top End Function Function DesktopWidth() api_GetWindowRect api_GetDesktopWindow() , struct_RECT Return struct_RECT\Right - struct_RECT\Left End Function Function DesktopHeight() api_GetWindowRect api_GetDesktopWindow() , struct_RECT Return struct_RECT\Bottom - struct_RECT\Top End Function Function GraphicsWindowWidth() api_GetWindowRect SystemProperty( "AppHWND" ) , struct_RECT Return struct_RECT\Right - struct_RECT\Left End Function Function GraphicsWindowHeight() api_GetWindowRect SystemProperty( "AppHWND" ) , struct_RECT Return struct_RECT\Bottom - struct_RECT\Top End Function ;------------------------------------------------------------------------------- ; * Older code (low level hacks) by EPS ;------------------------------------------------------------------------------- ;Function DesktopWidth() ; by EPS ;;======================================== ;; Ermittle Windows Desktopbreite ;;======================================== ; Local struct_rect% = CreateBank(16) ; ; api_GetWindowRect(api_GetDesktopWindow(),struct_rect) ; Local res = PeekInt(struct_rect,8) ; FreeBank struct_rect ; ; Return res ;End Function ; ; ;Function DesktopHeight() ; by EPS ;;======================================== ;; Ermittle Windows Desktophöhe ;;======================================== ; Local struct_rect% = CreateBank(16) ; ; api_GetWindowRect(api_GetDesktopWindow(),struct_rect) ; Local res = PeekInt(struct_rect,12) ; FreeBank struct_rect ; ; Return res ;End Function ;------------------------------------------------------------------------------- Function WindowDimensions_Demo() Graphics 160,120 , 0,3 SetBuffer BackBuffer() Repeat Cls Text 0,0 , "Canvas: "+GraphicsWidth()+"x"+GraphicsHeight() Text 0,10 , "Window: "+ActiveWindowWidth()+"x"+ActiveWindowHeight() Text 0,20 , "Desktop: "+DesktopWidth()+"x"+DesktopHeight() Flip Until KeyHit( 1 ) End End Function ;, ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;,,, , , ;;;,d%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&b. ;,d&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%b. ;&%&%&%&' ;%&%&%&% Fake full-screen ;&%&%&%&, ;'V&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%P` ;;;'V%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&%&P` ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;:::·· · · ;' ;------------------------------------------------------------------------------- ; GraphicsWindow( pixel_width , pixel_height , color_depth , window_mode ) ; - pixel_width, pixel_height, color_depth: same as Graphics ; - window_mode: same as Graphics, except mode 4; which is 'fake fullscreen'. ;------------------------------------------------------------------------------- ; File: api.User32.decls ; .lib "USER32.DLL" ; api_GetClientRect( hwnd% , lprect* ) : "GetClientRect" ; api_GetWindowLong% ( hwnd% , index% ) : "GetWindowLongA" ; api_SetWindowLong% ( hwnd% , index% , info% ) : "SetWindowLongA" ; api_SetWindowPos% ( hWnd% , Depth% , x1%,y1%,x2%,y2% , Actions% ) : "SetWindowPos" ;------------------------------------------------------------------------------- Const GraphicsWindow_SilentMode = False Type GraphicsWindow_Rect Field x1,y1 Field x2,y2 End Type Function GraphicsWindow( width,height , depth=32,mode=4 ) If width <= 0 Or height <= 0 GraphicsWindow_Error "Screen dimensions out of range: "+width+"x"+height End If Select depth Case 0,8,16,24,32 Default GraphicsWindow_Error "Invalid color depth: "+depth Return False End Select Select mode Case 0,1,2,3 ; 0: auto, 1: full, 2: window, 3: scaled window Graphics width,height , depth,mode Case 4 GraphicsWindow_FakeFullscreen width,height , depth Default GraphicsWindow_Error "Undefined window mode: "+mode Return False End Select Return True End Function Function GraphicsWindow_FakeFullscreen( w,h , d ) ; setup blitz graphics Graphics w,h , d,3 ; change window properties Local hwin = SystemProperty( "AppHWND" ) ; QueryObject( win , 1 ) ; blitzplus ; assume window has caption and frame -> toggle them off Local style = api_GetWindowLong( hwin , -16 ) Xor ($C00000+$40000) api_SetWindowLong hwin , -16 , style ; change window dimensions Local deskrect.GraphicsWindow_Rect = New GraphicsWindow_Rect api_GetClientRect api_GetDesktopWindow() , deskrect api_SetWindowPos hwin,0 , 0,0,deskrect\x2,deskrect\y2 , 4 Delete deskrect ;api_ShowWindow hwin , 3 ; maximize End Function Function GraphicsWindow_Error( message$ ) If GraphicsWindow_SilentMode DebugLog "() GraphicsWindow - "+message Else RuntimeError "() GraphicsWindow:"+Chr(13)+message End If End Function --v WindowHandling.BB (25 Dec 2010)
Mon, 17 Jan 2011, 09:36
Teasy	A few days ago I came across an old image rotation algorithm which is superfast by using 3 image skew operations. I do not remember exactly who created the function, but I optimized it a little bit ^^ I do know that the creator was one of the brilliant minds over on BlitzCoder, which could be one of the following: - Antony, Axeman1, BadJim, Bagels, BasicGamer2, Boomer, Chevron, CyberSeth, cR@wLy, DarkEagle, DJWoodgate, Eelco, Foppy, Gnasher, Gobble, LarsG, MutteringGoblin, ObviousDisaster, RepeatUntil, SirXriS, Skevo, World_Creator or someone else! Anyway, here's the function with example program I have inlined any required stuff from external files for your convenience ^^ ; * rotate an image using skewing (copyrect) ; usage: ; new_image = RotateImageSkew( old_image , rotate_angle ) ; notes: ; - returned image is twice as large ; - except for (multiples of) angles 0 and 180 ; - (!) no support yet for images with a non-centered hotspot (MidHandle) ; - angle can be both below 0 and above 360 ; - original image remains unchanged ; - this function is probably faster than most rotate functions ; version: ; - 16 Jan 2011 Rev 1 ; credits: ; - original by: Some brilliant mind(s) on BlitzCoder ^^ ; - revamped by: Teasy <TheChange@yahoo.com> Function RotateImageSkew( img , angle ) ; this function can be optimized ; - by doing 2 horizontal skew operations and 1 vertical ; instead of 2 vertical and 1 horizontal ; - and 90/270 deg rota can be done with 2 skews (1 hori, 1 verti) ; allow overflow If angle < 0 angle = 360 - Abs(angle) Mod 360 ElseIf angle >= 360 angle = angle Mod 360 End If ; no change If angle = 0 Return CopyImage(img) End If Local width=ImageWidth(img) Local height=ImageHeight(img) Local buf=ImageBuffer(img) Local xhandle=ImageXHandle(img) Local yhandle=ImageYHandle(img) Local img2,img3 Local img2b,img3b Local posx,posy Local imgw1,imgh1 ; quick flip xy If angle = 180 ; change orientation xhandle=ImageXHandle(img) yhandle=ImageYHandle(img) HandleImage img , 0,0 ; ori image -> 2nd image img2=CreateImage(width,height) img2b=ImageBuffer(img2) buf=ImageBuffer(img) imgh1=height-1 ; flip y For posy=0 To imgh1 CopyRect 0,posy,width,1 , 0,imgh1-posy , buf,img2b Next ; 2nd image -> 3rd image img3=CreateImage(width,height) img3b=ImageBuffer(img3) ; flip x imgw1=width-1 For posx=0 To imgw1 CopyRect posx,0,1,height , imgw1-posx,0 , img2b,img3b Next FreeImage img2 ; remember orientation HandleImage img,xhandle,yhandle HandleImage img3,xhandle,yhandle Return img3 End If ; decide whether to flip image Local flip180 If Cos(angle)>0 flip180=1 Else flip180=-1 angle=angle+180 If angle>=360 angle=angle-360 End If EndIf ; precalc rotation Local cosang#=Cos(angle) Local sinang#=Sin(angle) Local cs_factor#=(1-cosang)/sinang ; add padding to the (source) image as the new spare image Local spare=CreateImage(width2,height2) Local sparebuf=ImageBuffer(spare) CopyRect 0,0,width,height , width,height , buf,sparebuf ; offset handle by padding size (double) xhandle=xhandle+width/2 yhandle=yhandle+height/2 HandleImage spare , xhandle,yhandle width=width2 height=height2 ; make original image twice as large too (new target) ; (!) override variables img = CreateImage(width,height) buf = ImageBuffer(img) HandleImage img , xhandle,yhandle ; vertical skew operation Local y Local height1=height-1 For y=0 To height1 Local srcx=(y-yhandle)cs_factor Local srcy=(y-yhandle)+yhandle Local desx=xhandle Local desy=y+yhandle CopyRect srcx,srcy,width,1,desx,desy,sparebuf,buf Next ; clear spare image (becomes the target) Local gb=GraphicsBuffer() SetBuffer sparebuf Cls ; horizontal skew operation Local factor#=flip180sinang Local x Local width1=width-1 For x=0 To width1 srcx=(x-xhandle)/flip180+xhandle srcy=-(x-xhandle)factor desx=x+xhandle desy=yhandle CopyRect srcx,srcy,1,height,desx,desy,buf,sparebuf Next ; clear image (becomes the final image/target) SetBuffer buf Cls ; vertical skew operation For y=0 To height1 srcx=(y-yhandle)cs_factor srcy=(y-yhandle)/flip180+yhandle desx=xhandle desy=y+yhandle CopyRect srcx,srcy,width,1,desx,desy,sparebuf,buf Next FreeImage spare SetBuffer gb Return img End Function ;Include "\Dev\Blitz\Lib\Input.Def.BB" Const sx = 640 Const sy = 480 Graphics 800,600 , 0,2 Graphics sx,sy , 0,3 Const w = sx/4 Const h = sy/4 Local img = CreateImage(w,h) MidHandle img SetBuffer ImageBuffer(img) Color 0,128,255 Rect 0,0 , w,h Color 0,64,128 Rect 2,2 , w-4,h-4 Color 255,255,255 Text 10,10 , "1" , True,True Text w-10,10 , "2" , True,True Text 10,h-10 , "3" , True,True Text w-10,h-10 , "4" , True,True SetBuffer BackBuffer () Local mode=0 Local ang=-720 Repeat If KeyHit( Key_Space ) mode = Not mode End If If mode=0 ang = ang + 1 End If If mode=1 If KeyDown( Key_LeftShift ) Or KeyDown( Key_RightShift ) If KeyHit( Key_Left ) ang = ang - 1 ElseIf KeyHit( Key_Right ) ang = ang + 1 End If Else If KeyDown( Key_Left ) ang = ang - 1 ElseIf KeyDown( Key_Right ) ang = ang + 1 End If End If End If ;ang = RotateImageSkew_RangeInt( ang ) Local rota = RotateImageSkew( img , ang ) DrawImage rota , sx3/4,sy/2 DrawImage img , sx/4,sy/2 Local ms = MilliSecs () Local lasttime,frames If ms > lasttime + 999 Local FPS = frames frames = 0 lasttime = ms End If frames = frames + 1 Color 0,255,0 Text 12,12 , FPS+" FPS" Text 12,24 , "Mode "+mode+" <Space>" Text 12,36 , ang+" [<Shift>] <Left/Right>" Text 12,48 , "Original size: "+ImageWidth(img)+"x"+ImageHeight(img) Text 12,60 , "Rotated size: "+ImageWidth(rota)+"x"+ImageHeight(rota) FreeImage rota Flip False Cls Delay 1 Until KeyHit ( 1 ) End ;--[inc] ;------------------------------------------------------------------------------- ; ; Input Definitions (Mouse, keyboard) ; ;------------------------------------------------------------------------------- ; 27 Feb 2010 ; - Changed visual name 'Pad ..' to 'NumPad ..' ; 02 Jan 2007 ; - Last known edit (unknown) ;------------------------------------------------------------------------------- Local DefInput_Number ;======================================================================================================================; ; ® Numeric names Dim Numeric_Name$ ( 255 ) Numeric_Name ( 0 ) = "Zero" Numeric_Name ( 1 ) = "One" Numeric_Name ( 2 ) = "Two" Numeric_Name ( 3 ) = "Three" Numeric_Name ( 4 ) = "Four" Numeric_Name ( 5 ) = "Five" Numeric_Name ( 6 ) = "Six" Numeric_Name ( 7 ) = "Seven" Numeric_Name ( 8 ) = "Eight" Numeric_Name ( 9 ) = "Nine" Numeric_Name ( 10 ) = "Ten" Numeric_Name ( 11 ) = "Eleven" Numeric_Name ( 12 ) = "Twelve" For DefInput_Number = 13 To 255 Numeric_Name ( DefInput_Number ) = DefInput_Number Next ;======================================================================================================================; ; ® Mouse button values and names Const Button_Left% = 1 Const Button_Right% = 2 Const Button_Middle% = 3 Dim Button_Name$ ( 255 ) Button_Name ( 0 ) = "Button " + Numeric_Name ( 0 ) Button_Name ( Button_Left ) = "Left Button" Button_Name ( Button_Right ) = "Right Button" Button_Name ( Button_Middle ) = "Middle Button" For DefInput_Number = 4 To 255 Button_Name ( DefInput_Number ) = "Button " + Numeric_Name ( DefInput_Number ) Next ;======================================================================================================================; ; ® Joystick button names Dim Joy_Name$ ( 255 ) Joy_Name ( 0 ) = "Button " + Numeric_Name ( 0 ) Joy_Name ( 1 ) = "Primary Button" Joy_Name ( 2 ) = "Secondary Button" Joy_Name ( 3 ) = "Tertiary Button" Joy_Name ( 4 ) = "Quaternary Button" Joy_Name ( 5 ) = "Quinary Button" Joy_Name ( 6 ) = "Senary Button" Joy_Name ( 7 ) = "Septenary Button" Joy_Name ( 8 ) = "Octonary Button" Joy_Name ( 9 ) = "Nonary Button" Joy_Name ( 10 ) = "Denary Button" Joy_Name ( 11 ) = "Button Eleven" Joy_Name ( 12 ) = "Duodenary Button" For DefInput_Number = 13 To 255 Joy_Name ( DefInput_Number ) = "Button " + Numeric_Name ( DefInput_Number ) Next ;======================================================================================================================; ; ® Scancodes ;-( Numeric )--------------------------------------------; Const Key_1% = 2 Const Key_2% = 3 Const Key_3% = 4 Const Key_4% = 5 Const Key_5% = 6 Const Key_6% = 7 Const Key_7% = 8 Const Key_8% = 9 Const Key_9% = 10 Const Key_0% = 11 Dim Key_Num% ( 9 ) Key_Num ( 0 ) = Key_0 Key_Num ( 1 ) = Key_1 Key_Num ( 2 ) = Key_2 Key_Num ( 3 ) = Key_3 Key_Num ( 4 ) = Key_4 Key_Num ( 5 ) = Key_5 Key_Num ( 6 ) = Key_6 Key_Num ( 7 ) = Key_7 Key_Num ( 8 ) = Key_8 Key_Num ( 9 ) = Key_9 ;-( Alphabetic )-----------------------------------------; Const Key_Q% = 16 Const Key_W% = 17 Const Key_E% = 18 Const Key_R% = 19 Const Key_T% = 20 Const Key_Y% = 21 Const Key_U% = 22 Const Key_I% = 23 Const Key_O% = 24 Const Key_P% = 25 Const Key_A% = 30 Const Key_S% = 31 Const Key_D% = 32 Const Key_F% = 33 Const Key_G% = 34 Const Key_H% = 35 Const Key_J% = 36 Const Key_K% = 37 Const Key_L% = 38 Const Key_Z% = 44 Const Key_X% = 45 Const Key_C% = 46 Const Key_V% = 47 Const Key_B% = 48 Const Key_N% = 49 Const Key_M% = 50 Dim Key_Alpha% ( 26 ) Key_Alpha ( 1 ) = Key_A Key_Alpha ( 2 ) = Key_B Key_Alpha ( 3 ) = Key_C Key_Alpha ( 4 ) = Key_D Key_Alpha ( 5 ) = Key_E Key_Alpha ( 6 ) = Key_F Key_Alpha ( 7 ) = Key_G Key_Alpha ( 8 ) = Key_H Key_Alpha ( 9 ) = Key_I Key_Alpha ( 10 ) = Key_J Key_Alpha ( 11 ) = Key_K Key_Alpha ( 12 ) = Key_L Key_Alpha ( 13 ) = Key_M Key_Alpha ( 14 ) = Key_N Key_Alpha ( 15 ) = Key_O Key_Alpha ( 16 ) = Key_P Key_Alpha ( 17 ) = Key_Q Key_Alpha ( 18 ) = Key_R Key_Alpha ( 19 ) = Key_S Key_Alpha ( 20 ) = Key_T Key_Alpha ( 21 ) = Key_U Key_Alpha ( 22 ) = Key_V Key_Alpha ( 23 ) = Key_W Key_Alpha ( 24 ) = Key_X Key_Alpha ( 25 ) = Key_Y Key_Alpha ( 26 ) = Key_Z ;-( Numerical keypad )-----------------------------------; Const Key_Pad7% = 71 Const Key_Pad8% = 72 Const Key_Pad9% = 73 Const Key_Pad4% = 75 Const Key_Pad5% = 76 Const Key_Pad6% = 77 Const Key_Pad1% = 79 Const Key_Pad2% = 80 Const Key_Pad3% = 81 Const Key_Pad0% = 82 Dim Key_Pad% ( 9 ) Key_Pad ( 0 ) = Key_Pad0 Key_Pad ( 1 ) = Key_Pad1 Key_Pad ( 2 ) = Key_Pad2 Key_Pad ( 3 ) = Key_Pad3 Key_Pad ( 4 ) = Key_Pad4 Key_Pad ( 5 ) = Key_Pad5 Key_Pad ( 6 ) = Key_Pad6 Key_Pad ( 7 ) = Key_Pad7 Key_Pad ( 8 ) = Key_Pad8 Key_Pad ( 9 ) = Key_Pad9 ;-( Function keys )--------------------------------------; Const Key_Function1% = 59 Const Key_Function2% = 60 Const Key_Function3% = 61 Const Key_Function4% = 62 Const Key_Function5% = 63 Const Key_Function6% = 64 Const Key_Function7% = 65 Const Key_Function8% = 66 Const Key_Function9% = 67 Const Key_Function10% = 68 Const Key_Function11% = 87 Const Key_Function12% = 88 Dim Key_Function% ( 12 ) Key_Function ( 1 ) = Key_Function1 Key_Function ( 2 ) = Key_Function2 Key_Function ( 3 ) = Key_Function3 Key_Function ( 4 ) = Key_Function4 Key_Function ( 5 ) = Key_Function5 Key_Function ( 6 ) = Key_Function6 Key_Function ( 7 ) = Key_Function7 Key_Function ( 8 ) = Key_Function8 Key_Function ( 9 ) = Key_Function9 Key_Function ( 10 ) = Key_Function10 Key_Function ( 11 ) = Key_Function11 Key_Function ( 12 ) = Key_Function12 Const Key_F1% = Key_Function1 Const Key_F2% = Key_Function2 Const Key_F3% = Key_Function3 Const Key_F4% = Key_Function4 Const Key_F5% = Key_Function5 Const Key_F6% = Key_Function6 Const Key_F7% = Key_Function7 Const Key_F8% = Key_Function8 Const Key_F9% = Key_Function9 Const Key_F10% = Key_Function10 Const Key_F11% = Key_Function11 Const Key_F12% = Key_Function12 ;-( Shift states )---------------------------------------; Const Key_LeftShift% = 42 Const Key_RightShift% = 54 Const Key_LeftAlt% = 56 Const Key_RightAlt% = 184 Const Key_LeftCtrl% = 29 Const Key_RightCtrl% = 157 Const Key_CapsLock% = 58 Const Key_NumLock% = 69 Const Key_ScrollLock% = 70 Const Key_LeftAlternate% = Key_LeftAlt Const Key_RightAlternate% = Key_RightAlt Const Key_LeftControl% = Key_LeftCtrl Const Key_RightControl% = Key_RightCtrl Const Key_ShiftLeft% = Key_LeftShift Const Key_ShiftRight% = Key_RightShift Const Key_AltLeft% = Key_LeftAlt Const Key_AltRight% = Key_RightAlt Const Key_CtrlLeft% = Key_LeftCtrl Const Key_CtrlRight% = Key_RightCtrl ;-( Control keys )---------------------------------------; Const Key_Space% = 57 Const Key_Enter% = 28 Const Key_Tab% = 15 Const Key_BackSpace% = 14 Const Key_Insert% = 210 Const Key_Delete% = 211 Const Key_Home% = 199 Const Key_End% = 207 Const Key_PageUp% = 201 Const Key_PageDown% = 209 Const Key_Escape% = 1 Const Key_Pause% = 197 Const Key_LeftWindows% = 219 Const Key_RightWindows% = 220 Const Key_Apps% = 221 Const Key_Power% = 222 Const Key_Sleep% = 223 Const Key_Wake% = 227 Const Key_Return% = Key_Enter Const Key_SpaceBar% = Key_Space Const Key_PgUp% = Key_PageUp Const Key_PgDn% = Key_PageDown Const Key_Esc% = Key_Escape Const Key_LeftWin% = Key_LeftWindows Const Key_RightWin% = Key_RightWindows Const Key_Application% = Key_Apps Const Key_App% = Key_Apps Const Key_Del% = Key_Delete Const Key_BkSp% = Key_BackSpace ;-( Signs )----------------------------------------------; Const Key_BackQuote% = 41 Const Key_Minus% = 12 Const Key_Equals% = 13 Const Key_LeftBracket% = 26 Const Key_RightBracket% = 27 Const Key_BackSlash% = 43 Const Key_SemiColon% = 39 Const Key_Quote% = 40 Const Key_Comma% = 51 Const Key_Period% = 52 Const Key_Slash% = 53 ;-( Keypad controls )------------------------------------; Const Key_PadSlash% = 181 Const Key_PadAsterisk% = 55 Const Key_PadMinus% = 74 Const Key_PadPlus% = 78 Const Key_PadEnter% = 156 Const Key_PadPeriod% = 83 Const Key_PadStar% = Key_PadAsterisk ;-( Arrow keys )-----------------------------------------; Const Key_CursorUp% = 200 Const Key_CursorDown% = 208 Const Key_CursorLeft% = 203 Const Key_CursorRight% = 205 Const Key_ArrowUp% = Key_CursorUp Const Key_ArrowDown% = Key_CursorDown Const Key_ArrowLeft% = Key_CursorLeft Const Key_ArrowRight% = Key_CursorRight Const Key_Up% = Key_ArrowUp Const Key_Down% = Key_ArrowDown Const Key_Left% = Key_ArrowLeft Const Key_Right% = Key_ArrowRight ;======================================================================================================================; ; ® Key names Dim Key_Name$ ( 255 ) ;-( Numerical )------------------------------------------; Key_Name ( Key_1 ) = "1" Key_Name ( Key_2 ) = "2" Key_Name ( Key_3 ) = "3" Key_Name ( Key_4 ) = "4" Key_Name ( Key_5 ) = "5" Key_Name ( Key_6 ) = "6" Key_Name ( Key_7 ) = "7" Key_Name ( Key_8 ) = "8" Key_Name ( Key_9 ) = "9" Key_Name ( Key_0 ) = "0" ;-( Alphabetic )-----------------------------------------; Key_Name ( Key_Q ) = "Q" Key_Name ( Key_W ) = "W" Key_Name ( Key_E ) = "E" Key_Name ( Key_R ) = "R" Key_Name ( Key_T ) = "T" Key_Name ( Key_Y ) = "Y" Key_Name ( Key_U ) = "U" Key_Name ( Key_I ) = "I" Key_Name ( Key_O ) = "O" Key_Name ( Key_P ) = "P" Key_Name ( Key_A ) = "A" Key_Name ( Key_S ) = "S" Key_Name ( Key_D ) = "D" Key_Name ( Key_F ) = "F" Key_Name ( Key_G ) = "G" Key_Name ( Key_H ) = "H" Key_Name ( Key_J ) = "J" Key_Name ( Key_K ) = "K" Key_Name ( Key_L ) = "L" Key_Name ( Key_Z ) = "Z" Key_Name ( Key_X ) = "X" Key_Name ( Key_C ) = "C" Key_Name ( Key_V ) = "V" Key_Name ( Key_B ) = "B" Key_Name ( Key_N ) = "N" Key_Name ( Key_M ) = "M" ;-( Numeric keypad )-------------------------------------; Key_Name ( Key_Pad7 ) = "NumPad 7" Key_Name ( Key_Pad8 ) = "NumPad 8" Key_Name ( Key_Pad9 ) = "NumPad 9" Key_Name ( Key_Pad4 ) = "NumPad 4" Key_Name ( Key_Pad5 ) = "NumPad 5" Key_Name ( Key_Pad6 ) = "NumPad 6" Key_Name ( Key_Pad1 ) = "NumPad 1" Key_Name ( Key_Pad2 ) = "NumPad 2" Key_Name ( Key_Pad3 ) = "NumPad 3" Key_Name ( Key_Pad0 ) = "NumPad 0" ;-( Function keys )--------------------------------------; Key_Name ( Key_Function1 ) = "F1" Key_Name ( Key_Function2 ) = "F2" Key_Name ( Key_Function3 ) = "F3" Key_Name ( Key_Function4 ) = "F4" Key_Name ( Key_Function5 ) = "F5" Key_Name ( Key_Function6 ) = "F6" Key_Name ( Key_Function7 ) = "F7" Key_Name ( Key_Function8 ) = "F8" Key_Name ( Key_Function9 ) = "F9" Key_Name ( Key_Function10 ) = "F10" Key_Name ( Key_Function11 ) = "F11" Key_Name ( Key_Function12 ) = "F12" ;-( Shiftstate )-----------------------------------------; Key_Name ( Key_LeftShift ) = "Left Shift" Key_Name ( Key_RightShift ) = "Right Shift" Key_Name ( Key_LeftAlt ) = "Left Alt" Key_Name ( Key_RightAlt ) = "Right Alt" Key_Name ( Key_LeftCtrl ) = "Left Control" Key_Name ( Key_RightCtrl ) = "Right Control" Key_Name ( Key_CapsLock ) = "CapsLock" Key_Name ( Key_NumLock ) = "NumLock" Key_Name ( Key_ScrollLock ) = "ScrollLock" ;-( Control keys )---------------------------------------; Key_Name ( Key_Space ) = "SpaceBar" Key_Name ( Key_Enter ) = "Enter" Key_Name ( Key_Tab ) = "Tab" Key_Name ( Key_BackSpace ) = "BackSpace" Key_Name ( Key_Insert ) = "Insert" Key_Name ( Key_Delete ) = "Delete" Key_Name ( Key_Home ) = "Home" Key_Name ( Key_End ) = "End" Key_Name ( Key_PageUp ) = "PageUp" Key_Name ( Key_PageDown ) = "PageDown" Key_Name ( Key_Escape ) = "Escape" Key_Name ( Key_Pause ) = "Pause" Key_Name ( Key_LeftWindows ) = "Left Windows" Key_Name ( Key_RightWindows ) = "Right Windows" Key_Name ( Key_Apps ) = "Apps" Key_Name ( Key_Power ) = "Power" Key_Name ( Key_Sleep ) = "Sleep" Key_Name ( Key_Wake ) = "Wake" ;-( Signs )----------------------------------------------; Key_Name ( Key_BackQuote ) = "BackQuote `" Key_Name ( Key_Minus ) = "Minus -" Key_Name ( Key_Equals ) = "Equals =" Key_Name ( Key_LeftBracket ) = "Left Bracket [" Key_Name ( Key_RightBracket ) = "Right Bracket ]" Key_Name ( Key_BackSlash ) = "BackSlash \" Key_Name ( Key_SemiColon ) = "SemiColon ;" Key_Name ( Key_Quote ) = "Quote '" Key_Name ( Key_Comma ) = "Comma ," Key_Name ( Key_Period ) = "Period ." Key_Name ( Key_Slash ) = "Slash /" ;-( Keypad controls )------------------------------------; Key_Name ( Key_PadSlash ) = "NumPad Slash /" Key_Name ( Key_PadAsterisk ) = "NumPad Asterisk " Key_Name ( Key_PadMinus ) = "NumPad Minus -" Key_Name ( Key_PadPlus ) = "NumPad Plus +" Key_Name ( Key_PadEnter ) = "NumPad Enter" Key_Name ( Key_PadPeriod ) = "NumPad Period ." ;-( Cursors )--------------------------------------------; Key_Name ( Key_CursorUp ) = "Cursor Up" Key_Name ( Key_CursorDown ) = "Cursor Down" Key_Name ( Key_CursorLeft ) = "Cursor Left" Key_Name ( Key_CursorRight ) = "Cursor Right" ;======================================================================================================================; --v copyrectrotaskewopti 1e2.bb
Fri, 19 Feb 2021, 06:55
spinal	looking at rotation again, trying to figure put what all of the magic numbers are in my above post -=-=- Check out my excellent homepage!
Fri, 19 Feb 2021, 08:04
Jayenkai	Making me wish, again, that I had quick and easy Blitz access.. Any degree, or are we talking 90 degree rotations?! -=-=- ''Load, Next List!''
Fri, 19 Feb 2021, 08:12
spinal	I've got most of it figured I think... Any degree, Graphics 640,480,0,2 Graphics 320,240,0,3 SetBuffer BackBuffer() pic = CreateImage(120,12) SetBuffer ImageBuffer(pic) Color 255,0,0 Rect 0,0,120,12,1 Color 0,0,255 Text 0,0,"ABCDEFGHIJKLMNO" angle = 0 While Not KeyHit(1) mx = MouseX() my = MouseY() SetBuffer BackBuffer() Cls angle=angle+1 If angle > 360 Then angle = angle - 360 hx = ImageWidth(pic)/2 ; x handle of original image hy = ImageHeight(pic)/2 ; y handle of original image cx = mx ; x handle of rotated image? cy = my ; y handle of rotated image? minx = -hx maxx = minx + ImageWidth(pic) miny = -hy maxy = miny + ImageHeight(pic) For ex = 0 To 320 ; render whole screen as noy doing any math to find rotated co-ords For ey = 0 To 240 ; Unrotate unrotatex=(ex-cx) * Cos(-angle) - (ey-cy) * Sin(-angle) unrotatey=(ex-cx) * Sin(-angle) + (ey-cy) * Cos(-angle) If unrotatex > minx And unrotatex < maxx And unrotatey > miny And unrotatey < maxy Then ; Find colour at that point SetBuffer ImageBuffer(pic) GetColor(unrotatex + hx,unrotatey + hy) SetBuffer BackBuffer() ; Slap it back in.. Plot ex, ey End If Next Next Color 0,0,0 Rect cx-1,cy-1,3,3,1 Color 255,255,255 Rect cx-1,cy-1,3,3,0 Flip Wend End --v So far I think I just need to discover the bounding box of the rotated image as to not have to pixel the whole screen! -=-=- Check out my excellent homepage!
Fri, 19 Feb 2021, 09:12
Jayenkai	Surely it'd be easier to loop through the image and determine it's co-ord on the screen, rather than looping the entire screen...? Wouldn't it? -=-=- ''Load, Next List!''
Fri, 19 Feb 2021, 09:34
spinal	but that would leave gaps. The method would be as follows I expect... find each of the 4 corners, rotate them around the handle, find the furthest in each direction then iterate inside the resulting box. -=-=- Check out my excellent homepage!
Fri, 19 Feb 2021, 09:51
Jayenkai	Do it twice over the size of the image. First time, draw a 2x2 pixel splot, then the second time, the single pixel. That should (!!) hopefully help fill in any sub-pixels. -=-=- ''Load, Next List!''
Fri, 19 Feb 2021, 10:41
cyangames	Or, do it as was, then interpolate the surrounding pixels for the dead pixels, unless they're also dead pixels. -=-=- Web / Game Dev, occasionally finishes off coding games also!