How to Clear a Bitmap in VCL
How to clear a bitmap that was declared in the .cpp as follows:
Graphics::TBitmap * Bitmap1 = new Graphics::TBitmap;
All the examples I find are for Firemonkey and there it seems quite simple
MyBitmap = new TBitmap(0,0);
...
MyBitmap->Clear(claWhite);
or
MyBitmap->ClearRect(MyRect);
But Clear() and ClearRect() are not members of TBitmap in VCL
I expect I should delete Bitmap1; in order to clear it, but then how to re-declare it, so that it is still global to all methods in the form?
Thanks in advance.
c++builder vcl rad-studio
asked Nov 13 '18 at 14:10
BarryKBarryK
94
add a comment |
How to clear a bitmap that was declared in the .cpp as follows:
Graphics::TBitmap * Bitmap1 = new Graphics::TBitmap;
All the examples I find are for Firemonkey and there it seems quite simple
MyBitmap = new TBitmap(0,0);
...
MyBitmap->Clear(claWhite);
or
MyBitmap->ClearRect(MyRect);
But Clear() and ClearRect() are not members of TBitmap in VCL
I expect I should delete Bitmap1; in order to clear it, but then how to re-declare it, so that it is still global to all methods in the form?
Thanks in advance.
c++builder vcl rad-studio
asked Nov 13 '18 at 14:10
BarryKBarryK
94
add a comment |
How to clear a bitmap that was declared in the .cpp as follows:
Graphics::TBitmap * Bitmap1 = new Graphics::TBitmap;
All the examples I find are for Firemonkey and there it seems quite simple
MyBitmap = new TBitmap(0,0);
...
MyBitmap->Clear(claWhite);
or
MyBitmap->ClearRect(MyRect);
But Clear() and ClearRect() are not members of TBitmap in VCL
I expect I should delete Bitmap1; in order to clear it, but then how to re-declare it, so that it is still global to all methods in the form?
Thanks in advance.
c++builder vcl rad-studio
asked Nov 13 '18 at 14:10
BarryKBarryK
94
How to clear a bitmap that was declared in the .cpp as follows:
Graphics::TBitmap * Bitmap1 = new Graphics::TBitmap;
All the examples I find are for Firemonkey and there it seems quite simple
MyBitmap = new TBitmap(0,0);
...
MyBitmap->Clear(claWhite);
or
MyBitmap->ClearRect(MyRect);
But Clear() and ClearRect() are not members of TBitmap in VCL
I expect I should delete Bitmap1; in order to clear it, but then how to re-declare it, so that it is still global to all methods in the form?
Thanks in advance.
c++builder vcl rad-studio
c++builder vcl rad-studio
asked Nov 13 '18 at 14:10
BarryKBarryK
94
asked Nov 13 '18 at 14:10
BarryKBarryK
94
asked Nov 13 '18 at 14:10
BarryKBarryK
94
asked Nov 13 '18 at 14:10
BarryKBarryK
94
asked Nov 13 '18 at 14:10
BarryKBarryK
94
94
add a comment |
add a comment |
1 Answer
1
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oldest
votes
You don't need to delete and recreate the TBitmap. Simply draw a new image over top of it, for instance by using its Canvas->FillRect() method (that is essentially what the FMX examples are doing), eg:
Bitmap1->Brush->Color = clWhite;
Bitmap1->Canvas->FillRect(Rect(0, 0, Bitmap1->Width, Bitmap1->Height));
answered Nov 13 '18 at 20:16
Remy LebeauRemy Lebeau
334k18254450
add a comment |
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1 Answer
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1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
You don't need to delete and recreate the TBitmap. Simply draw a new image over top of it, for instance by using its Canvas->FillRect() method (that is essentially what the FMX examples are doing), eg:
Bitmap1->Brush->Color = clWhite;
Bitmap1->Canvas->FillRect(Rect(0, 0, Bitmap1->Width, Bitmap1->Height));
answered Nov 13 '18 at 20:16
Remy LebeauRemy Lebeau
334k18254450
add a comment |
You don't need to delete and recreate the TBitmap. Simply draw a new image over top of it, for instance by using its Canvas->FillRect() method (that is essentially what the FMX examples are doing), eg:
Bitmap1->Brush->Color = clWhite;
Bitmap1->Canvas->FillRect(Rect(0, 0, Bitmap1->Width, Bitmap1->Height));
answered Nov 13 '18 at 20:16
Remy LebeauRemy Lebeau
334k18254450
add a comment |
You don't need to delete and recreate the TBitmap. Simply draw a new image over top of it, for instance by using its Canvas->FillRect() method (that is essentially what the FMX examples are doing), eg:
Bitmap1->Brush->Color = clWhite;
Bitmap1->Canvas->FillRect(Rect(0, 0, Bitmap1->Width, Bitmap1->Height));
answered Nov 13 '18 at 20:16
Remy LebeauRemy Lebeau
334k18254450
You don't need to delete and recreate the TBitmap. Simply draw a new image over top of it, for instance by using its Canvas->FillRect() method (that is essentially what the FMX examples are doing), eg:
Bitmap1->Brush->Color = clWhite;
Bitmap1->Canvas->FillRect(Rect(0, 0, Bitmap1->Width, Bitmap1->Height));
answered Nov 13 '18 at 20:16
Remy LebeauRemy Lebeau
334k18254450
answered Nov 13 '18 at 20:16
Remy LebeauRemy Lebeau
334k18254450
answered Nov 13 '18 at 20:16
Remy LebeauRemy Lebeau
334k18254450
answered Nov 13 '18 at 20:16
Remy LebeauRemy Lebeau
334k18254450
334k18254450
add a comment |
add a comment |
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