commit 82fe694f1304ccbcb83c8ec478e05045426b39a1 Author: L. David Baron <dbaron@dbaron.org> Date: Fri Feb 14 21:29:12 2014 -0800 Bug 541855 - Add in the error tolerance before calling the timing function, so that we allow more error for steeper functions, and less error for most. r=dholbert, a=test-only --- layout/style/test/test_transitions.html | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/layout/style/test/test_transitions.html b/layout/style/test/test_transitions.html index 75b90a2..d00c28d 100644 --- a/layout/style/test/test_transitions.html +++ b/layout/style/test/test_transitions.html @@ -430,6 +430,19 @@ function check_transition_value(func, start_time, end_time, start_value, end_value, cval, desc, xfail) { + /** + * Compute the value at a given time |elapsed|, by normalizing the + * input to the timing function using start_time and end_time and + * then turning the output into a value using start_value and + * end_value. + * + * The |error_direction| argument should be either -1, 0, or 1, + * suggesting adding on a little bit of error, to allow for the + * cubic-bezier calculation being an approximation. The amount of + * error is proportional to the slope of the timing function, since + * the error is added to the *input* of the timing function (after + * normalization to 0-1 based on start_time and end_time). + */ function value_at(elapsed, error_direction) { var time_portion = (elapsed - start_time) / (end_time - start_time); if (time_portion < 0) @@ -438,7 +451,7 @@ function check_transition_value(func, start_time, end_time, time_portion = 1; // Assume a small error since bezier computation can be off slightly. // (This test's computation is probably more accurate than Mozilla's.) - var value_portion = func(time_portion) + error_direction * 0.0015; + var value_portion = func(time_portion + error_direction * 0.0005); if (value_portion < 0) value_portion = 0; else if (value_portion > 1)