LibGfx: Move all image loaders and writers to a subdirectory

Userland/Libraries/LibGfx/ImageFormats/BMPWriter.h

@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2020, Ben Jilks <benjyjilks@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/ByteBuffer.h>
+
+namespace Gfx {
+
+class Bitmap;
+
+// This is not a nested struct to work around https://llvm.org/PR36684
+struct BMPWriterOptions {
+    enum class DibHeader : u32 {
+        Info = 40,
+        V3 = 56,
+        V4 = 108,
+        V5 = 124,
+    };
+    DibHeader dib_header = DibHeader::V5;
+
+    Optional<ReadonlyBytes> icc_data;
+};
+
+class BMPWriter {
+public:
+    using Options = BMPWriterOptions;
+    static ErrorOr<ByteBuffer> encode(Bitmap const&, Options options = Options {});
+
+private:
+    BMPWriter() = default;
+
+    ErrorOr<ByteBuffer> dump(Bitmap const&, Options options);
+
+    enum class Compression : u32 {
+        BI_RGB = 0,
+        BI_BITFIELDS = 3,
+    };
+
+    static ByteBuffer compress_pixel_data(ByteBuffer, Compression);
+
+    Compression m_compression { Compression::BI_BITFIELDS };
+
+    int m_bytes_per_pixel { 4 };
+    bool m_include_alpha_channel { true };
+};
+
+}