/// <summary>
/// Returns the background size node with the correctly adjusted values for dpi and output units.
/// </summary>
/// <param name="assembledImage">The assembled image.</param>
/// <param name="dpiFactor">The background dpi.</param>
/// <returns>The background-size node.</returns>
private IEnumerable <DeclarationNode> CreateBackgroundSizeNode(AssembledImage assembledImage, float dpiFactor)
{
var calcWidth = (float?)Math.Round((assembledImage.SpriteWidth ?? 0f) * this.outputUnitFactor / dpiFactor, 3);
var calcHeight = (float?)Math.Round((assembledImage.SpriteHeight ?? 0f) * this.outputUnitFactor / dpiFactor, 3);
var widthTermNode = new TermNode(
calcWidth.UnaryOperator(),
calcWidth.CssUnitValue(this.outputUnit),
null,
null,
null,
null);
var heightTermNode = new TermNode(
calcHeight.UnaryOperator(),
calcHeight.CssUnitValue(this.outputUnit),
null,
null,
null,
null);
var termWithOperatorNodes = new List <TermWithOperatorNode>
{
new TermWithOperatorNode(ImageAssembleConstants.SingleSpace, heightTermNode)
};
var newBackgroundSizeNode =
new DeclarationNode(
ImageAssembleConstants.BackgroundSize,
new ExprNode(
widthTermNode,
termWithOperatorNodes.ToSafeReadOnlyCollection(), null),
null,
null);
return(new[]
{
// add a comment to help with sprite debugging
CreateDebugDeclarationComment("-wg-background-size-params", " (sprite size: " + assembledImage.SpriteWidth + "px " + assembledImage.SpriteHeight + "px) (output unit factor: " + this.outputUnitFactor + ") (dpi: " + dpiFactor + ") (imageposition:" + assembledImage.ImagePosition + ")"),
newBackgroundSizeNode
});
}
/// <summary>Gets the assembled image information from the dictionary</summary>
/// <param name="parsedImagePath">The parsed url</param>
/// <param name="backgroundPosition">The background position node</param>
/// <param name="assembledImage">The assembled image path</param>
/// <returns>The assembled image object</returns>
private bool TryGetAssembledImage(string parsedImagePath, BackgroundPosition backgroundPosition, out AssembledImage assembledImage)
{
if (this.availableSourceImages == null && string.IsNullOrWhiteSpace(this.cssPath))
{
throw new BuildWorkflowException("Need either images or css path to be able to set a valid image file.");
}
assembledImage = null;
if (this.inputImages == null)
{
return(false);
}
// TODO - Spec. issue: What are the supported path formats supported in CSS?
// For optimization, should the relative paths be enforced?
// Get the full path of parsed image file (convert from ../../ to absolute path)
if (parsedImagePath.StartsWith("hash://", StringComparison.OrdinalIgnoreCase))
{
parsedImagePath = parsedImagePath.Substring(7);
}
if (this.availableSourceImages != null)
{
if (!this.availableSourceImages.TryGetValue(parsedImagePath.NormalizeUrl(), out parsedImagePath))
{
if (!string.IsNullOrWhiteSpace(this.missingImage))
{
parsedImagePath = this.availableSourceImages.TryGetValue(this.missingImage);
}
}
}
else
{
parsedImagePath = parsedImagePath.MakeAbsoluteTo(this.cssPath);
}
var imagePosition = ImagePosition.Left;
if (backgroundPosition != null)
{
imagePosition = backgroundPosition.GetImagePositionInVerticalSprite();
}
// Try to locate the input image in the list
assembledImage = this.inputImages.FirstOrDefault(inputImage => inputImage.ImagePosition == imagePosition && inputImage.OriginalFilePath.Equals(parsedImagePath, StringComparison.OrdinalIgnoreCase));
if (assembledImage != null &&
assembledImage.OutputFilePath != null)
{
assembledImage.RelativeOutputFilePath =
!string.IsNullOrWhiteSpace(this.destinationDirectory)
? Path.Combine(this.prependToDestination, assembledImage.OutputFilePath.MakeRelativeToDirectory(this.destinationDirectory).Replace('\\', '/'))
: assembledImage.OutputFilePath.MakeRelativeTo(this.cssPath);
if (!string.IsNullOrWhiteSpace(assembledImage.RelativeOutputFilePath))
{
assembledImage.RelativeOutputFilePath = assembledImage.RelativeOutputFilePath.Replace('\\', '/');
}
return(true);
}
return(false);
}
/// <summary>
/// Sets the background-size priority node if the dpi does not equal 1, also replace an existing one if it exists.
/// </summary>
/// <param name="updatedDeclarations">The updated declarations.</param>
/// <param name="backgroundSizeNode">The node containing the possible existing background size.</param>
/// <param name="dpiFactor">The background dpi.</param>
/// <param name="assembledImage">The assembled image.</param>
private void SetBackgroundSize(List <DeclarationNode> updatedDeclarations, DeclarationNode backgroundSizeNode, float dpiFactor, AssembledImage assembledImage)
{
if (backgroundSizeNode != null)
{
updatedDeclarations.Remove(backgroundSizeNode);
}
// if the DPI factor is not 1.0, then we need to output a properly-scaled background-size property,
// regardless of the the output units we want (if we don't specify an output unit, pixels is used).
// but if we specify an output unit, we need to output the background-size property even if the DPI is 1.0,
// in order to properly handle the browser default font-size change functionality.
if ((dpiFactor != 1f || this.outputUnit != null) &&
assembledImage.SpriteHeight.HasValue && assembledImage.SpriteWidth.HasValue)
{
updatedDeclarations.AddRange(this.CreateBackgroundSizeNode(assembledImage, dpiFactor));
}
}
