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Fix calculation in clutter_cubic_bezier
The calculation for cubic bezier curves had an extra multiplication by 3 which was causing the curve to go over 1.0 very quickly. This had the affect of making test-animation appear to complete much before the completed signal is emitted.
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@ -1282,7 +1282,7 @@ clutter_cubic_bezier (ClutterAlpha *alpha,
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* B(t) = (1 - t)^3 * P_0
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* + 3t * (1 - t)^2 * P_1
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* + 3t^2 * (1 - t) * P_2
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* + 3t^3 * P_3 (with t included in [0, 1])
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* + t^3 * P_3 (with t included in [0, 1])
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*
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* the P_0 and P_3 points are set to (0, 0) and (1, 1) respectively,
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* and the curve never passes through P_1 and P_2 - with these two
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@ -1294,14 +1294,14 @@ clutter_cubic_bezier (ClutterAlpha *alpha,
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*
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* B(t) = 3t * (1 - t)^2 * P_1
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* + 3t^2 * (1 - t) * P_2
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* + 3t^3 * P_3 (with t included in [0, 1])
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* + t^3 * P_3 (with t included in [0, 1])
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*
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* and, similarly, since the final point is (1, 1) we can simplify
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* it further to:
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*
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* B(t) = 3t * (1 - t)^2 * P_1
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* + 3t^2 * (1 - t) * P_2
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* + 3t^3 (with t included in [0, 1])
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* + t^3 (with t included in [0, 1])
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*
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* since an alpha function has only a time parameter and we have two
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* coordinates for each point, we pass the time as the first
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@ -1314,11 +1314,11 @@ clutter_cubic_bezier (ClutterAlpha *alpha,
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b_t = 3 * t * pow (1 - t, 2) * x_1
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+ 3 * pow (t, 2) * (1 - t) * x_2
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+ 3 * pow (t, 3);
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+ pow (t, 3);
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res = 3 * b_t * pow (1 - b_t, 2) * y_1
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+ 3 * pow (b_t, 2) * (1 - b_t) * y_2
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+ 3 * pow (b_t, 3);
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+ pow (b_t, 3);
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return res;
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}
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