89 lines
3.2 KiB
C#
89 lines
3.2 KiB
C#
///////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// Microsoft Research Singularity
|
|
//
|
|
// Copyright (c) Microsoft Corporation. All rights reserved.
|
|
//
|
|
// File: BitmapInfoHeader.cs
|
|
//
|
|
// Note:
|
|
//
|
|
|
|
using System;
|
|
using System.Runtime.InteropServices;
|
|
|
|
using Microsoft.SingSharp;
|
|
using Microsoft.Singularity;
|
|
using Microsoft.Singularity.Channels;
|
|
|
|
namespace Microsoft.Singularity.Io
|
|
{
|
|
[CLSCompliant(false)]
|
|
[StructLayout(LayoutKind.Explicit)]
|
|
public pointerfree struct BITMAPINFOHEADER {
|
|
[FieldOffset( 0)] public uint biSize;
|
|
[FieldOffset( 4)] public int biWidth;
|
|
[FieldOffset( 8)] public int biHeight;
|
|
[FieldOffset(12)] public ushort biPlanes;
|
|
[FieldOffset(14)] public ushort biBitCount;
|
|
[FieldOffset(16)] public uint biCompression;
|
|
[FieldOffset(20)] public uint biSizeImage;
|
|
[FieldOffset(24)] public int biXPelsPerMeter;
|
|
[FieldOffset(28)] public int biYPelsPerMeter;
|
|
[FieldOffset(30)] public uint biClrUsed;
|
|
[FieldOffset(32)] public uint biClrImportant;
|
|
|
|
public static BITMAPINFOHEADER Read(byte[]! in ExHeap buffer,
|
|
int offset, out int used)
|
|
{
|
|
if (buffer == null || offset < 0 ||
|
|
offset + sizeof(BITMAPINFOHEADER) > buffer.Length) {
|
|
unchecked {
|
|
Tracing.Log(Tracing.Error,
|
|
"BITMAPINFOHEADER Read(offset={0}, length={1})",
|
|
(UIntPtr)(uint)offset,
|
|
(UIntPtr)(uint)buffer.Length);
|
|
}
|
|
throw new OverflowException("Read source invalid.");
|
|
}
|
|
|
|
used = offset + sizeof(BITMAPINFOHEADER);
|
|
|
|
ref BITMAPINFOHEADER bmih = ref buffer[offset];
|
|
return bmih;
|
|
}
|
|
|
|
public RGB[] ReadPalette(byte[]! in ExHeap buffer, int offset, out int used)
|
|
{
|
|
if (biClrUsed == 0 && biBitCount >= 24) {
|
|
used = offset;
|
|
return null;
|
|
}
|
|
|
|
int count = (biClrUsed != 0) ? (int)biClrUsed : (1 << biBitCount);
|
|
|
|
if (buffer == null || offset < 0 ||
|
|
offset + count * sizeof(uint) > buffer.Length) {
|
|
unchecked {
|
|
Tracing.Log(Tracing.Error,
|
|
"RGB Read(offset={0}, count={1}, length={2}",
|
|
(UIntPtr)(uint)offset,
|
|
(UIntPtr)(uint)count,
|
|
(UIntPtr)(uint)buffer.Length);
|
|
}
|
|
throw new OverflowException("Read source invalid.");
|
|
}
|
|
|
|
RGB[] values = new RGB [count];
|
|
used = offset;
|
|
offset += sizeof(uint);
|
|
|
|
for (int i = 0; i < count; i++) {
|
|
values[i] = new RGB(buffer[2+offset], buffer[1+offset], buffer[0+offset]);
|
|
offset += sizeof(uint);
|
|
}
|
|
return values;
|
|
}
|
|
}
|
|
} // namespace Microsoft.Singularity.Io
|