✨ Add code to update touchscreen on SD+ devices.

Not tested yet, but at least it is not forgotten.
hexawyz · Jan 14, 2025 · fc14c56 · fc14c56
1 parent 7654e93
commit fc14c56
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diff --git a/Docs/Stream Decl XL.md b/Docs/Stream Decl XL.md
@@ -56,6 +56,14 @@ Firmware 1.01.000 end is 115272 bytes.
 02 09 08 <IsFinalPacket:B8> <PacketIndex:U16> <PacketLength:U16> <Data:U8[]>
 ```
 
+#### Command `0C` - Stream Deck + - Write image region
+
+```
+02 0C <Left:U16> <Top:U16> <Width:U16> <Height:U16> <IsFinalPacket:B8> <PacketIndex:U16> <PacketLength:U16> <Zero:U8> <Data:U8[]>
+```
+
+Stream Deck + devices would also include a touch screen, that can be updated entirely or partially using this command.
+
 ### Feature report `03` - Write - Device configuration
 
 #### Command `02` - Reset
@@ -143,6 +151,8 @@ Example:
 08 04 08 6000 6000 0004 5802 02 00 01 04 04 00 0000 0000 0000000000000000000000
 ```
 
+NB: This likely includes touch screen width and height for SD+ devices.
+
 ### Feature report `09` - Read - Device total uptime
 
 ```

diff --git a/src/Exo/Devices/Exo.Devices.Elgato.StreamDeck/StreamDeckDevice.cs b/src/Exo/Devices/Exo.Devices.Elgato.StreamDeck/StreamDeckDevice.cs
@@ -298,8 +298,8 @@ static ReadOnlyMemory<byte> UpdateRequest(Span<byte> buffer, ushort maxSliceLeng
 			ushort sliceLength = isLastSlice ? (ushort)remaining.Length : maxSliceLength;
 
 			buffer[3] = isLastSlice ? (byte)0x01 : (byte)0x00;
-			Unsafe.WriteUnaligned(ref buffer[4], BitConverter.IsLittleEndian ? sliceLength : BinaryPrimitives.ReverseEndianness(sliceLength));
-			Unsafe.WriteUnaligned(ref buffer[6], BitConverter.IsLittleEndian ? index : BinaryPrimitives.ReverseEndianness(index));
+			LittleEndian.Write(ref buffer[4], sliceLength);
+			LittleEndian.Write(ref buffer[6], index);
 			remaining.Span[..sliceLength].CopyTo(buffer[8..]);
 
 			return remaining[sliceLength..];
@@ -317,6 +317,51 @@ static ReadOnlyMemory<byte> UpdateRequest(Span<byte> buffer, ushort maxSliceLeng
 		}
 	}
 
+	public async Task SetTouchScreenRegionAsync(ushort x, ushort y, ushort width, ushort height, ReadOnlyMemory<byte> data, CancellationToken cancellationToken)
+	{
+		var buffer = WriteBuffer;
+
+		ushort maxSliceLength = checked((ushort)(buffer.Length - 16));
+
+		static ReadOnlyMemory<byte> PrepareRequest(Span<byte> buffer, ushort x, ushort y, ushort width, ushort height, ushort maxSliceLength, ReadOnlyMemory<byte> remaining)
+		{
+			buffer[0] = 0x02;
+			buffer[1] = 0x0C;
+			LittleEndian.Write(ref buffer[2], x);
+			LittleEndian.Write(ref buffer[4], y);
+			LittleEndian.Write(ref buffer[6], width);
+			LittleEndian.Write(ref buffer[8], height);
+			LittleEndian.Write(ref buffer[15], 0);
+
+			return UpdateRequest(buffer, maxSliceLength, remaining, 0);
+		}
+
+		static ReadOnlyMemory<byte> UpdateRequest(Span<byte> buffer, ushort maxSliceLength, ReadOnlyMemory<byte> remaining, ushort index)
+		{
+			bool isLastSlice = remaining.Length <= maxSliceLength;
+			ushort sliceLength = isLastSlice ? (ushort)remaining.Length : maxSliceLength;
+
+			// NB: For some reason, the slice index & length are inversed compared to the call to set the key image 🤷
+			buffer[10] = isLastSlice ? (byte)0x01 : (byte)0x00;
+			LittleEndian.Write(ref buffer[11], index);
+			LittleEndian.Write(ref buffer[13], sliceLength);
+			remaining.Span[..sliceLength].CopyTo(buffer[16..]);
+
+			return remaining[sliceLength..];
+		}
+
+		var remaining = data;
+
+		remaining = PrepareRequest(buffer.Span, x, y, width, height, maxSliceLength, remaining);
+		ushort index = 0;
+		while (true)
+		{
+			await _stream.WriteAsync(buffer, cancellationToken).ConfigureAwait(false);
+			if (remaining.Length == 0) break;
+			remaining = UpdateRequest(buffer.Span, maxSliceLength, remaining, ++index);
+		}
+	}
+
 	public async Task SetScreenSaverImageDataAsync(ReadOnlyMemory<byte> data, CancellationToken cancellationToken)
 	{
 		var buffer = WriteBuffer;
@@ -339,8 +384,8 @@ static ReadOnlyMemory<byte> UpdateRequest(Span<byte> buffer, ushort maxSliceLeng
 
 			// NB: For some reason, the slice index & length are inversed compared to the call to set the key image 🤷
 			buffer[3] = isLastSlice ? (byte)0x01 : (byte)0x00;
-			Unsafe.WriteUnaligned(ref buffer[4], BitConverter.IsLittleEndian ? index : BinaryPrimitives.ReverseEndianness(index));
-			Unsafe.WriteUnaligned(ref buffer[6], BitConverter.IsLittleEndian ? sliceLength : BinaryPrimitives.ReverseEndianness(sliceLength));
+			LittleEndian.Write(ref buffer[4], index);
+			LittleEndian.Write(ref buffer[6], sliceLength);
 			remaining.Span[..sliceLength].CopyTo(buffer[8..]);
 
 			return remaining[sliceLength..];