Magic-Mirror/gecko-dev
1
0
Fork 0
mirror of https://github.com/mozilla/gecko-dev.git synced 2024-11-25 05:41:12 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Add some documenting comments to the image encoders; no bug

Browse Source
This commit is contained in:
Jonathan Watt 2014-06-25 12:59:55 +01:00
parent abbc718b0c
commit f886ddcddc
2 changed files with 39 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
image/encoders/ico/nsICOEncoder.cpp
View File

@ -157,7 +157,9 @@ nsICOEncoder::AddImageFrame(const uint8_t* aData,
}
mImageBufferCurr = mImageBufferStart;
// The icon buffer does not include the BFH at all.
// Icon files that wrap a BMP file must not include the BITMAPFILEHEADER
// section at the beginning of the encoded BMP data, so we must skip over
// BFH_LENGTH bytes when adding the BMP content to the icon file.
mICODirEntry.mBytesInRes = BMPImageBufferSize - BFH_LENGTH + andMaskSize;
// Encode the icon headers

37
image/src/ICOFileHeaders.h
View File

@ -14,28 +14,63 @@ namespace mozilla {
#define PNGSIGNATURESIZE 8
#define BMPFILEHEADERSIZE 14
/**
* The header that comes right at the start of an icon file. (This
* corresponds to the Windows ICONDIR structure.)
*/
struct IconFileHeader
{
/**
* Must be set to 0;
*/
uint16_t mReserved;
/**
* 1 for icon (.ICO) image (or 2 for cursor (.CUR) image (icon with the
* addition of a hotspot), but we don't support cursor).
*/
uint16_t mType;
/**
* The number of BMP/PNG images contained in the icon file.
*/
uint16_t mCount;
};
/**
* For each BMP/PNG image that the icon file containts there must be a
* corresponding icon dir entry. (This corresponds to the Windows
* ICONDIRENTRY structure.) These entries are encoded directly after the
* IconFileHeader.
*/
struct IconDirEntry
{
uint8_t mWidth;
uint8_t mHeight;
/**
* The number of colors in the color palette of the BMP/PNG that this dir
* entry corresponds to, or 0 if the image does not use a color palette.
*/
uint8_t mColorCount;
/**
* Should be set to 0.
*/
uint8_t mReserved;
union {
uint16_t mPlanes; // ICO
uint16_t mXHotspot; // CUR
};
union {
uint16_t mBitCount; // ICO
uint16_t mBitCount; // ICO (bits per pixel)
uint16_t mYHotspot; // CUR
};
/**
* "bytes in resource" is the length of the encoded BMP/PNG that this dir
* entry corresponds to.
*/
uint32_t mBytesInRes;
/**
* The offset of the start of the encoded BMP/PNG that this dir entry
* corresponds to (from the start of the icon file).
*/
uint32_t mImageOffset;
};