Re: WebDrawingArea to Image

[Bruce Steers <bsteers4@xxxxxxxxx>]

Ps.  it would probably be best to use your initial idea and "snapshot" the
ready drawn canvas image using GetImageData.

All other options are probably going to be pretty complicated.

Respects
BruceS

On Tue, 14 Jul 2026, 21:04 Bruce Steers, <bsteers4@xxxxxxxxx> wrote:

> There is a javascript function in html canvas API , GetImageData
> https://www.w3schools.com/jsref/canvas_getimagedata.asp
>
> There is nothing like that built in to the WebDrawingArea though but you
> should be able to use javascript for the canvas api.
>
> Respects
> BruceS
>
> On Tue, 14 Jul 2026 at 18:44, Olivier Cruilles <olivier.cruilles@xxxxxxxx>
> wrote:
>
>> In fact I would like to get all the <canvas><script>…</script></canvas>
>> code produced sent to the Web Browser in the way to inject it into an
>> <iframe></iframe> balise that will be used by the Web Browser to Print it.
>>
>> I’m already doing that for any html page I want to print by the Web
>> Browser but I don’t find a way to catch the WebDrawingArea html+javascript
>> code sent to the Browser by Gambas.
>>
>> Any idea
>>
>>
>> Olivier
>>
>> Le 14 juill. 2026 à 11:21, Olivier Cruilles <olivier.cruilles@xxxxxxxx>
>> a écrit :
>>
>> Hello,
>>
>>
>> I would like to create an Image file from the drawing commands I use into
>> a WebDrawingArea object, like we can do it for DrawingArea object.
>> It is possible to do it like that ?
>>
>> Public Sub Create_Image()
>>
>>   Dim hImg As New Image(Paint.Width, Paint.Height, Color.White,
>> Image.Standard)
>>
>>   Htmldata = WebDrawingAreaCourbe.ToHTML()
>>
>>   Paint.Begin(hImg)
>>   Paint.Scale(1, 1)
>>
>>     'Exemple of code to draw
>>     Paint.LineWidth = 1
>>
>>     Paint.Rectangle(50, 50, 150, 150)
>>     Paint.Stroke(Color.Red, True)
>>     Paint.Fill(Color.SetAlpha(Color.SoftBlue, 192))
>>
>>     Paint.Rectangle(80, 80, 150, 150)
>>     Paint.Stroke(Color.SetAlpha(Color.Yellow, 64))
>>
>>     Paint.Arc(100, 100, 60)
>>     Paint.Fill(Color.Red)
>>     Paint.Rectangle(20, 20, 120, 70)
>>     Paint.Fill(Color.SetAlpha(Color.Royal, 64))
>>
>>     Paint.Ellipse(20, 20, 120, 70, 0, -Pi / 2)
>>     Paint.Stroke(Color.Green)
>>
>>     Paint.Rectangle(40, 80, 120, 70)
>>     Paint.Brush = Paint.LinearGradient(80, 140, 100, 120, [Color.Red,
>> Color.Green, Color.Violet], [0, 0.5, 1])
>>     Paint.Fill()
>>
>>     Paint.Rectangle(60, 90, 120, 70)
>>     Paint.Brush = Paint.LinearGradient(220, 200, 340, 200, [Color.Red,
>> Color.Green, Color.Violet], [0, 0.5, 1])
>>     Paint.Fill()
>>
>>     Paint.Arc(100, 320, 40)
>>     Paint.Brush = Paint.RadialGradient(100, 320, 2, 100, 320, 40, ["red",
>> "yellow", "lightblue"], [0, 0.6, 1])
>>     Paint.Fill()
>>
>>   Paint.End()
>>
>>   Try hImg.Save("/tmp/imagecourbe.png")
>>   If Error Then
>>     ModLogs.EcrireLogs("Error during image saving ! - Error: " &
>> Error.Text)
>>   Endif
>>
>> End
>>
>> I know it's possible with Cairo library too, but through gb.gui.web
>> component I not sure.
>>
>> Any idea ?
>>
>> Thank you
>>
>> -- Olivier
>>
>>
>>
>>