/// <summary>
/// Executes the image optimizer on a specific subdirectory of the root image directory (non-recursive)
/// </summary>
/// <param name="path">The path to the directory to be rebuilt</param>
/// <param name="checkIfFilesWereModified">Indicate whether the directory should only be rebuilt if files were modified</param>
/// <returns>False if the directory does not exist</returns>
internal static bool ProcessDirectory(string path, bool checkIfFilesWereModified)
{
// Check if directory was deleted
if (!Directory.Exists(path))
{
return(false);
}
try {
if (checkIfFilesWereModified && !HaveFilesBeenModified(path))
{
return(true);
}
// Make a list of the disk locations of each image
List <string> imageLocations = new List <string>();
foreach (string extension in _extensions)
{
imageLocations.AddRange(Directory.GetFiles(path, extension));
}
// Make sure to delete any existing sprites (or other images with the filename sprite###.imageExtension)
imageLocations.RemoveAll(DeleteSpriteFile);
// Make sure to not include the blank.gif file
string blankFile = HostingEnvironment.MapPath(Path.Combine(SpriteDirectoryRelativePath, BlankFileName)).ToUpperInvariant();
imageLocations.RemoveAll(file => blankFile == file.ToUpperInvariant());
// Import settings from settings file
ImageSettings settings = GetSettings(path);
// Create pointer to the CSS output file
lock (_lockObj) {
using (TextWriter cssHighCompatOutput = new StreamWriter(Path.Combine(path, HighCompatibilityCssFileName), append: false),
cssLowCompatOutput = new StreamWriter(Path.Combine(path, LowCompatibilityCssFileName), append: false)) {
PerformOptimizations(path, settings, cssHighCompatOutput, cssLowCompatOutput, imageLocations);
// Merge with a user's existing CSS file(s)
MergeExternalCss(path, cssHighCompatOutput, cssLowCompatOutput);
}
}
imageLocations.Clear();
foreach (string extension in _extensions)
{
imageLocations.AddRange(Directory.GetFiles(path, extension));
}
SaveFileModificationData(path);
return(true);
}
catch (Exception) {
if (!Directory.Exists(path))
{
return(false);
}
throw;
}
}
private static ImageSettings GetSettings(string path)
{
ImageSettings settings = new ImageSettings();
string settingFileLocation = LocateSettingFile(path);
if (settingFileLocation != null)
{
XmlTextReader settingsData;
// Open the settings file. If it fails here, we throw an exception since we expect the file to be there and readable.
using (settingsData = new XmlTextReader(settingFileLocation)) {
while (settingsData.Read())
{
if (settingsData.NodeType == XmlNodeType.Element)
{
string nodeName = settingsData.Name;
if (nodeName.Equals("FileFormat", StringComparison.OrdinalIgnoreCase))
{
settings.Format = settingsData.ReadElementContentAsString().Trim('.');
}
else if (nodeName.Equals("Quality", StringComparison.OrdinalIgnoreCase))
{
settings.Quality = settingsData.ReadElementContentAsInt();
}
else if (nodeName.Equals("MaxSize", StringComparison.OrdinalIgnoreCase))
{
settings.MaxSize = settingsData.ReadElementContentAsInt();
}
else if (nodeName.Equals("BackgroundColor", StringComparison.OrdinalIgnoreCase))
{
string output = settingsData.ReadElementContentAsString();
int temp = Int32.Parse(output, System.Globalization.NumberStyles.HexNumber, CultureInfo.InvariantCulture);
settings.BackgroundColor = Color.FromArgb(temp);
}
else if (nodeName.Equals("Base64Encoding", StringComparison.OrdinalIgnoreCase))
{
settings.Base64 = settingsData.ReadElementContentAsBoolean();
}
else if (nodeName.Equals("TileInYAxis", StringComparison.OrdinalIgnoreCase))
{
settings.TileInYAxis = settingsData.ReadElementContentAsBoolean();
}
}
}
}
return(settings);
}
return(settings);
}
private static void GenerateSprite(string path, ImageSettings settings, int x, int y, int spriteNumber, List <Bitmap> images, TextWriter cssHighCompatOutput, TextWriter cssLowCompatOutput)
{
// Create a drawing surface and add the images to it
// Since we'll be padding each image by 1px later on, we need to increase the sprites's size correspondingly.
if (settings.TileInYAxis)
{
y += images.Count;
}
else
{
x += images.Count;
}
using (Bitmap sprite = new Bitmap(x, y)) {
using (Graphics drawingSurface = Graphics.FromImage(sprite)) {
// Set the background to the specs from the settings file
drawingSurface.Clear(settings.BackgroundColor);
// Make the final sprite and save it
int xOffset = 0;
int yOffset = 0;
foreach (Bitmap image in images)
{
drawingSurface.DrawImage(image, new Rectangle(xOffset, yOffset, image.Width, image.Height));
// Add the CSS data
GenerateCss(xOffset, yOffset, spriteNumber, settings.Format, settings.Base64, image, cssHighCompatOutput);
GenerateCss(xOffset, yOffset, spriteNumber, settings.Format, false, image, cssLowCompatOutput);
if (settings.TileInYAxis)
{
// pad each image in the sprite with a 1px margin
yOffset += image.Height + 1;
}
else
{
// pad each image in the sprite with a 1px margin
xOffset += image.Width + 1;
}
}
// Set the encoder parameters and make the image
try {
using (EncoderParameters spriteEncoderParameters = new EncoderParameters(1)) {
spriteEncoderParameters.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, settings.Quality);
// Attempt to save the image to disk with the specified encoder
sprite.Save(Path.Combine(path, GenerateSpriteFileName(spriteNumber, settings.Format)), GetEncoderInfo(settings.Format), spriteEncoderParameters);
}
}
catch (Exception) {
// If errors occur, get the CLI to auto-choose an encoder. Unfortunately this means that the quality settings will be not used.
try {
sprite.Save(Path.Combine(path, GenerateSpriteFileName(spriteNumber, settings.Format)));
}
catch (Exception) {
// If errors occur again, try to save as a png
sprite.Save(Path.Combine(path, GenerateSpriteFileName(spriteNumber, "png")));
}
}
}
}
}
private static void PerformOptimizations(string path, ImageSettings settings, TextWriter cssHighCompatOutput, TextWriter cssLowCompatOutput, List <string> imageLocations)
{
// Create a list containing each image (in Bitmap format), and calculate the total size (in pixels) of final image
int x = 0;
int y = 0;
int imageIndex = 0;
long size = 0;
int spriteNumber = 0;
List <Bitmap> images = new List <Bitmap>();
try {
foreach (string imagePath in imageLocations)
{
// If the image is growing above the specified max file size, make the sprite with the existing images
// and add the new image to the next sprite list
if ((imageIndex > 0) && IsSpriteOversized(settings.MaxSize, size, imagePath))
{
GenerateSprite(path, settings, x, y, spriteNumber, images, cssHighCompatOutput, cssLowCompatOutput);
// Clear the existing images
foreach (Bitmap image in images)
{
image.Dispose();
}
// Reset variables to initial values, and increment the spriteNumber
images.Clear();
x = 0;
y = 0;
imageIndex = 0;
size = 0;
spriteNumber++;
}
// Add the current image to the list of images that are to be processed
images.Add(new Bitmap(imagePath));
// Use the image tag to store its name
images[imageIndex].Tag = MakeCssSelector(imagePath, SpriteDirectoryRelativePath);
// Find the total pixel size of the sprite based on the tiling direction
if (settings.TileInYAxis)
{
y += images[imageIndex].Height;
if (x < images[imageIndex].Width)
{
x = images[imageIndex].Width;
}
}
else
{
x += images[imageIndex].Width;
if (y < images[imageIndex].Height)
{
y = images[imageIndex].Height;
}
}
// Update the filesize size of the bitmap list
size += (new FileInfo(imagePath)).Length;
imageIndex++;
}
// Merge the final list of bitmaps into a sprite
if (imageIndex != 0)
{
GenerateSprite(path, settings, x, y, spriteNumber, images, cssHighCompatOutput, cssLowCompatOutput);
}
}
finally {
// Close the CSS file and clear the images list
foreach (Bitmap image in images)
{
image.Dispose();
}
}
}