diff --git a/spec/ttml2.xml b/spec/ttml2.xml index e03d5839e..ad14dac58 100644 --- a/spec/ttml2.xml +++ b/spec/ttml2.xml @@ -628,6 +628,17 @@ and may specify inline overrides to styling.

Sets .

+ + + +

A styling attribute or its interned representation +as a style property +the definition of which specifies it to be animatable by discrete +or continuous animation. +A styling attribute the definition of which (1) specifies its animatability as none or +(2) does not specify its animatability is referred to as a non-animatable style.

+ + @@ -8587,9 +8598,9 @@ whether (and how) style is animatable, and semantic basis (derivation).

style property definition table, the definition of applies to specified by , §1.4.2.3, applies to this specification.

-

For animatable styles, the term discrete refers to the use of either a set +

For animatable styles, the term discrete refers to the use of either a set element or an animate element with the discrete value for its -<calculation-mode>. The term continuous refers to +<calculation-mode>. The term continuous refers to the use of an animate element with a linear, paced, or spline value for its <calculation-mode>. The term none indicates the style is not animatable.

@@ -16924,7 +16935,7 @@ set of E, SSS(E);

element type of E is not an inline animation element, then for each conditionally included inline animation element child A of element E, -merge the specified style set of A, +merge the animatable styles of the specified style set of A, SSS(A), into the specified style set of E, SSS(E);

@@ -18605,7 +18616,8 @@ styling of content.

animate -

The animate element expresses a series of changes (animations) to be applied (targeted) to one or more styling attributes of associated elements.

+

The animate element expresses a series of changes (animations) to be applied (targeted) +to one or more animatable styles of associated elements.

An animate element may appear as either (1) a child of a content element or a region element, referred to as inline animation, or @@ -18651,6 +18663,8 @@ where the list (sequence) of animation values adhere to the <animation-value-list> syntax, and where each constituent <animation-value> adheres to the syntax of the specified attribute.

+

Targeting a non-animatable style is +considered an error and must be ignored for the purpose of presentation processing.

In contrast with , §19.2.12, a single animate element, as defined here, may be used to perform continuous animations on a set of targeted style attributes instead of being limited to targeting a @@ -18857,8 +18871,8 @@ defined to be coterminous with the root set -

The set element expresses one or more a discrete changes (animations) to be applied (targeted) to styling attributes -of associated elements.

+

The set element expresses one or more a discrete changes (animations) to be applied (targeted) +to one or more animatable styles of associated elements.

A set element may appear as either (1) a child of a content element or a region element, referred to as inline animation, or @@ -18899,6 +18913,8 @@ must specify an xml:id at

Style attributes targeted by a set element are specified directly using attributes in the TT Style Namespaces or in a namespace that is not some TT Namespace, where the single target animation (key) value adheres to the <animation-value> syntax.

+

Targeting a non-animatable style is +considered an error and must be ignored for the purpose of presentation processing.

In contrast with , §19.2.13, a single set element, as defined here, may be used to perform discrete animations on a set of targeted styling attributes instead of being limited to targeting a