Proposal: Inclusion of user defined gradients using graphics/SVG in the Office specification

["Paul Langille" <Paul.Langille@corel.com>]

Title: Message

I propose keeping the existing gradient specification in it's current form. In order to allow others to extend this specification, we should add an attribute to allow users to create their own 'gradient' types. By allowing a vector format such as SVG to describe this gradient type, we can handle cases that we cannot previously predict. The changes to the format are:

1. Add userdefinedgradient to the list of gradient-style that can be supported.
   • <!ENTITY % gradient-style "(linear|axial|radial|ellipsoid|square|rectangular|userdefinedgradient)">
2. Add draw:userdefinedgradient to the attribute list of draw:transparency and draw:gradient.
• This would be an XLINK to access the graphic stored within the overall file that would define the gradient. The size would be defined by the view within the graphic. The top-left, bottom right coordinate of the view of the graphic would be scaled to the size of the item being affected by the gradient.
3. Add draw:userdefinedgradientitem to the an appropriate section to hold the gradient rendering information. The XLINK/URL would reference/index this item.
• Would contain the graphic and gradient co-ordinate/transformation information.
• The mapping system will be defined inside of the gradient descriptor, such as to use Red component, RGB component, brightness component, or ALPHA component from the graphic itself. This will be an attribute corresponding to the info to use from the graphic.
• RGB, R, G, B, ALPHA, H, S, B, C, M,Y, K are all color systems that should be able to be used from the original graph.