Re: [Lazarus] Rotating a bitmap
On Mon, 27 Oct 2008, Luiz Americo Pereira Camara wrote: > Michael Van Canneyt escreveu: > > All I need is to display a text at a 90° angle. Since GTK 1 doesn't > > support rotated text (hint hint), I draw the text on a bitmap, rotate > > that 90 degrees and display the bitmap, when I detect GTK1 as a widget > > set :-) > > > > > Take a look at the unit i pointed. It has a class that does specifically > this. Indeed it does. Thanks for the hint. I'll use my implementation since it uses the built-in rotated font if available. (and it was ready anyway :-) ) Michael.___ Lazarus mailing list Lazarus@lazarus.freepascal.org http://www.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Rotating a bitmap
Michael Van Canneyt escreveu: > All I need is to display a text at a 90° angle. Since GTK 1 doesn't > support rotated text (hint hint), I draw the text on a bitmap, rotate > that 90 degrees and display the bitmap, when I detect GTK1 as a widget > set :-) > Take a look at the unit i pointed. It has a class that does specifically this. Luiz ___ Lazarus mailing list Lazarus@lazarus.freepascal.org http://www.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Rotating a bitmap
On Mon, 27 Oct 2008, Reenen Laurie wrote: > I had a similar problem... Eventually I moved on to GLscene... > > Though obviously it's probably not at all what you want to do, but it's > pretty easy to rotate things there. :-) > > obj.rollangle := obj.rollangle + 90; > > You can use an orthogonal camera if you don't want / need the perspective. > > You can even let it "slowly" rotate using a cadencer, but let's not jump the > gun here. All I need is to display a text at a 90° angle. Since GTK 1 doesn't support rotated text (hint hint), I draw the text on a bitmap, rotate that 90 degrees and display the bitmap, when I detect GTK1 as a widget set :-) Requiring OpenGL for this would be slightly over the top, I'm sure you'll agree :-) Michael.___ Lazarus mailing list Lazarus@lazarus.freepascal.org http://www.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Rotating a bitmap
I had a similar problem... Eventually I moved on to GLscene... Though obviously it's probably not at all what you want to do, but it's pretty easy to rotate things there. :-) obj.rollangle := obj.rollangle + 90; You can use an orthogonal camera if you don't want / need the perspective. You can even let it "slowly" rotate using a cadencer, but let's not jump the gun here. Regards, -Reenen 2008/10/27 Michael Van Canneyt <[EMAIL PROTECTED]> > > > On Mon, 27 Oct 2008, Vincent Snijders wrote: > > > 2008/10/27 Michael Van Canneyt <[EMAIL PROTECTED]>: > > > Hi, > > > > > > How can I rotate a bitmap 90° counterclockwise ? > > > > > > Alternatively, how can I read/write the pixels in the bitmap ? > > > I found ReadChannels/WriteChannels from RawImage, but they > > > use a strange kind of position object which I don't understand :( > > > > Maybe the lazintf example > > (http://svn.freepascal.org/svn/lazarus/trunk/examples/lazintfimage/) > > can help. It rotates an image. > > Exactly what I needed. TLazIntfImage is the missing link :-) > > Thanks to everyone for the links ! > > Michael. > ___ > Lazarus mailing list > Lazarus@lazarus.freepascal.org > http://www.lazarus.freepascal.org/mailman/listinfo/lazarus > > -- o__ ,_.>/ _ (_)_\(_)___ ...speed is good ___ I believe five out of four people have a problem with fractions. ___ Lazarus mailing list Lazarus@lazarus.freepascal.org http://www.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Rotating a bitmap
On Mon, 27 Oct 2008, Vincent Snijders wrote: > 2008/10/27 Michael Van Canneyt <[EMAIL PROTECTED]>: > > Hi, > > > > How can I rotate a bitmap 90° counterclockwise ? > > > > Alternatively, how can I read/write the pixels in the bitmap ? > > I found ReadChannels/WriteChannels from RawImage, but they > > use a strange kind of position object which I don't understand :( > > Maybe the lazintf example > (http://svn.freepascal.org/svn/lazarus/trunk/examples/lazintfimage/) > can help. It rotates an image. Exactly what I needed. TLazIntfImage is the missing link :-) Thanks to everyone for the links ! Michael.___ Lazarus mailing list Lazarus@lazarus.freepascal.org http://www.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Rotating a bitmap
On Mon, 27 Oct 2008, Graeme Geldenhuys wrote: > 2008/10/27 Michael Van Canneyt <[EMAIL PROTECTED]>: > > Hi, > > > > How can I rotate a bitmap 90° counterclockwise ? > > > To save you the trouble... :-) > > http://www.efg2.com/Lab/ImageProcessing/RotateScanline.htm > http://www.delphi-central.com/tutorials/RotateBitmapBitBlt.aspx > http://delphi.about.com/cs/adptips2001/a/bltip1201_4.htm Thank you, but I already saw those prior to asking my questions. None of the techniques described there work in Lazarus. Michael. ___ Lazarus mailing list Lazarus@lazarus.freepascal.org http://www.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Rotating a bitmap
2008/10/27 Michael Van Canneyt <[EMAIL PROTECTED]>: > Hi, > > How can I rotate a bitmap 90° counterclockwise ? > > Alternatively, how can I read/write the pixels in the bitmap ? > I found ReadChannels/WriteChannels from RawImage, but they > use a strange kind of position object which I don't understand :( Maybe the lazintf example (http://svn.freepascal.org/svn/lazarus/trunk/examples/lazintfimage/) can help. It rotates an image. Vincent ___ Lazarus mailing list Lazarus@lazarus.freepascal.org http://www.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Rotating a bitmap
2008/10/27 Michael Van Canneyt <[EMAIL PROTECTED]>: > Hi, > > How can I rotate a bitmap 90° counterclockwise ? > > Alternatively, how can I read/write the pixels in the bitmap ? > I found ReadChannels/WriteChannels from RawImage, but they > use a strange kind of position object which I don't understand :( > > (an alternate answer is to implement rotated fonts in GTK1 ;)) > > Michael. > ___ > Lazarus mailing list > Lazarus@lazarus.freepascal.org > http://www.lazarus.freepascal.org/mailman/listinfo/lazarus > > ___ Lazarus mailing list Lazarus@lazarus.freepascal.org http://www.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Rotating a bitmap
2008/10/27 Michael Van Canneyt <[EMAIL PROTECTED]>: > Hi, > > How can I rotate a bitmap 90° counterclockwise ? Wouldn't a rotation matrix do the trick? I remember the old fpGUI code (gfxbase.pas) unit used a 3x3 matrix to do translations and scalations calculations. I would imagine the same could be applied for rotation. Wikipedia has some articles on rotation matrix, but the formulas look scary. ;-) Google revealed a lot of links on rotation matrix. > Alternatively, how can I read/write the pixels in the bitmap ? The TFPCustomCanvas.Colors[] array? Regards, - Graeme - ___ fpGUI - a cross-platform Free Pascal GUI toolkit http://opensoft.homeip.net/fpgui/ ___ Lazarus mailing list Lazarus@lazarus.freepascal.org http://www.lazarus.freepascal.org/mailman/listinfo/lazarus
Re: [Lazarus] Rotating a bitmap
2008/10/27 Michael Van Canneyt <[EMAIL PROTECTED]>: > Hi, > > How can I rotate a bitmap 90° counterclockwise ? To save you the trouble... :-) http://www.efg2.com/Lab/ImageProcessing/RotateScanline.htm http://www.delphi-central.com/tutorials/RotateBitmapBitBlt.aspx http://delphi.about.com/cs/adptips2001/a/bltip1201_4.htm Regards, - Graeme - ___ fpGUI - a cross-platform Free Pascal GUI toolkit http://opensoft.homeip.net/fpgui/ ___ Lazarus mailing list Lazarus@lazarus.freepascal.org http://www.lazarus.freepascal.org/mailman/listinfo/lazarus
[Lazarus] Rotating a bitmap
Hi, How can I rotate a bitmap 90° counterclockwise ? Alternatively, how can I read/write the pixels in the bitmap ? I found ReadChannels/WriteChannels from RawImage, but they use a strange kind of position object which I don't understand :( (an alternate answer is to implement rotated fonts in GTK1 ;)) Michael.___ Lazarus mailing list Lazarus@lazarus.freepascal.org http://www.lazarus.freepascal.org/mailman/listinfo/lazarus
