Skia4Delphi - RAD Studio Exclusive Features

• 1 Vulkan Backend
• 2 Effects and Filters with Skia Shading Language (SKSL)
• 3 Animated Codec: WebP Encoder
• 4 Printer
• 5 C++ Builder Support
  • 5.1 See Also

uses
 System.StartUpCopy,
 FMX.Forms,
 FMX.Types,
 FMX.Skia,
 Unit1 in 'Unit1.pas' {Form1};
 
{$R *.res}
 
begin
 GlobalUseSkia := True;
 GlobalUseSkiaRasterWhenAvailable := False;
 GlobalUseVulkan := True;
 Application.Initialize;
 ...

Effects and Filters with Skia Shading Language (SKSL)

When using Skia app rendering with GPU acceleration instead of rasterization, Firemonkey leverages the powerful SKSL to render effects and filters. This approach not only provides superior performance compared to the current method, but also enhances Skia Canvas's efficiency.

Moreover, one of the main advantages of using SKSL for creating effects and filters is simplified maintenance. A single shader codebase works consistently across all platforms, eliminating the need for multiple codes specific to each backend API and ensuring uniform results.

Animated Codec: WebP Encoder

The Skia version integrated with RAD Studio supports encoding of animated WebP. With Firemonkey's new animated codec foundation, it is possible to register new encoders capable of encoding and/or decoding.

WebP is one of the most widely used formats on the web due to its superior compression compared to JPEG, resulting in smaller file sizes while maintaining higher quality. It also offers animation capabilities similar to GIFs but with lossless frames, meaning there is no loss of quality and/or some compression. Additionally, it supports transparency, making it a highly versatile format.

To provide an example, assume there are five 400x400 PNG images (frames) named frame1.png, frame2.png, frame3.png, frame4.png, and frame5.png, with each frame having an 80-millisecond interval. To create an animated WebP, first include the units "FMX.Graphics" and "FMX.Skia," then utilize the following code:

uses
 FMX.Graphics;
 
procedure TForm1.Button1Click(Sender: TObject);
begin
 var LAnimatedCodec := TAnimatedCodecManager.CreateAnimatedCodec('.webp');
 try
 for var I := 1 to 5 do
 begin
 var LBitmap := TBitmap.Create;
 try
 LBitmap.LoadFromFile(Format('frame%d.png', [I]));
 LAnimatedCodec.AddFrame(LBitmap, 80);
 finally
 LBitmap.Free;
 end;
 end;
 if not LAnimatedCodec.SaveToFile('image.webp') then
 raise Exception.Create('Could not save animated WebP.');
 finally
 LAnimatedCodec.Free;
 end;
end;

Printer

When Skia is enabled, Firemonkey's native Printer for Windows will use Skia as its backend for the physical printer, and ensure support for all other platforms through PDF document printing, with the optional XPS printing also available when the target is Windows. On iOS and Android, the printer will generate a printable file which will be automatically shared upon completion.

To use Firemonkey's printer, follow the simple example below:

uses
 FMX.Printer;
 
procedure TForm1.Button1Click(Sender: TObject);
begin
 Printer.BeginDoc;
 try
 if Printer.Canvas.BeginScene then
 try
 Form1.PaintTo(Printer.Canvas);
 finally
 Printer.Canvas.EndScene;
 end;
 finally
 Printer.EndDoc;
 end;
end;

You can select custom paper sizes or predefined sizes. By default, A4 paper is configured, but it can be easily changed as demonstrated in the example below:

uses
 FMX.Printer;
 
initialization
 // Alter the document's paper size
 TPrinterDocument.SetDocumentPaper(TDocumentPaper.Letter);
end.

Depending on the target devices, document size, and complexity, the UI may become unresponsive due to the resource-intensive operation. In such cases, you can use background thread printing on all platforms to print directly to a stream, as shown in the example below:

uses
 FMX.Printer;
 
procedure TThread1.Execute;
begin
 var LStream := TMemoryStream.Create;
 try
 var LPrinter := PrinterDocumentClass.Create;
 try
 LPrinter.BeginDoc(LStream);
 try
 if LPrinter.Canvas.BeginScene then
 begin
 try
 { TODO: Draw page 1 }
 finally
 LPrinter.Canvas.EndScene;
 end;
 end;
 
 LPrinter.NewPage;
 if LPrinter.Canvas.BeginScene then
 begin
 try
 { TODO: Draw page 2 }
 finally
 LPrinter.Canvas.EndScene;
 end;
 end;
 finally
 LPrinter.EndDoc;
 end;
 finally
 LPrinter.Free;
 end;
 { TODO: Something with LStream }
 finally
 LStream.Free;
 end;
end;

C++ Builder Support

RAD Studio offers Skia4Delphi support for C++ Builder, including the project's main demo written in C++ to assist users in its implementation. To access the demo during RAD Studio installation, opt to install the Samples, or visit Embarcadero's GitHub repository to download it.

See Also

• Skia4Delphi