Add Catmull-Rom spline smooth animation interpolation.

[mlt] / src / framework / mlt_animation.c

diff --git a/src/framework/mlt_animation.c b/src/framework/mlt_animation.c
index 449ee2fe0daceb8e4b46476af3dca43b57e4a9ea..b0791bd8dac0e7c8a23d69a7257c92b06b85b75e 100644 (file)
--- a/src/framework/mlt_animation.c
+++ b/src/framework/mlt_animation.c
@@ -60,6 +60,8 @@ void mlt_animation_interpolate( mlt_animation self )
                {
                        if ( !current->item.is_key )
                        {
+                               double progress;
+                               mlt_property points[4];
                                animation_node prev = current->prev;
                                animation_node next = current->next;
 
@@ -68,18 +70,14 @@ void mlt_animation_interpolate( mlt_animation self )
 
                                if ( !prev )
                                        current->item.is_key = 1;
-                               if ( current->item.keyframe_type == mlt_keyframe_discrete )
-                               {
-                                       mlt_property_pass( current->item.property, prev->item.property );
-                               }
-                               else
-                               {
-                                       mlt_property_interpolate( current->item.property,
-                                               prev->item.property, next->item.property,
-                                               current->item.frame - prev->item.frame,
-                                               next->item.frame - prev->item.frame,
-                                               self->fps, self->locale );
-                               }
+                               points[0] = prev->prev? prev->prev->item.property : prev->item.property;
+                               points[1] = prev->item.property;
+                               points[2] = next->item.property;
+                               points[3] = next->next? next->next->item.property : next->item.property;
+                               progress = current->item.frame - prev->item.frame;
+                               progress /= next->item.frame - prev->item.frame;
+                               mlt_property_interpolate( current->item.property, points, progress,
+                                       self->fps, self->locale, current->item.keyframe_type );
                        }
 
                        // Move to the next item
@@ -229,8 +227,10 @@ int mlt_animation_parse_item( mlt_animation self, mlt_animation_item item, const
 
                        // The character preceeding the equal sign indicates interpolation method.
                        p = strchr( value, '=' ) - 1;
-                       if ( p[0] == '|' )
+                       if ( p[0] == '|' || p[0] == '!' )
                                item->keyframe_type = mlt_keyframe_discrete;
+                       else if ( p[0] == '~' )
+                               item->keyframe_type = mlt_keyframe_smooth;
                        else
                                item->keyframe_type = mlt_keyframe_linear;
                        value = &p[2];
@@ -240,10 +240,6 @@ int mlt_animation_parse_item( mlt_animation self, mlt_animation_item item, const
                if ( item->frame < 0 )
                        item->frame += self->length;
 
-               // Obtain the current value at this position - this allows new
-               // frames to be created which don't specify all values
-               mlt_animation_get_item( self, item, item->frame );
-
                // Set remainder of string as item value.
                mlt_property_set_string( item->property, value );
                item->is_key = 1;
@@ -292,17 +288,17 @@ int mlt_animation_get_item( mlt_animation self, mlt_animation_item item, int pos
                // Interpolation needed.
                else
                {
+                       double progress;
+                       mlt_property points[4];
+                       points[0] = node->prev? node->prev->item.property : node->item.property;
+                       points[1] = node->item.property;
+                       points[2] = node->next->item.property;
+                       points[3] = node->next->next? node->next->next->item.property : node->next->item.property;
+                       progress = position - node->item.frame;
+                       progress /= node->next->item.frame - node->item.frame;
+                       mlt_property_interpolate( item->property, points, progress,
+                               self->fps, self->locale, item->keyframe_type );
                        item->is_key = 0;
-                       if ( node->item.keyframe_type == mlt_keyframe_discrete )
-                       {
-                               mlt_property_pass( item->property, node->item.property );
-                       }
-                       else
-                       {
-                               mlt_property_interpolate( item->property, node->item.property, node->next->item.property,
-                                       position - node->item.frame, node->next->item.frame - node->item.frame,
-                                       self->fps, self->locale );
-                       }
                }
        }
        else
@@ -505,19 +501,20 @@ char *mlt_animation_serialize_cut( mlt_animation self, int in, int out )
                        if ( ret )
                        {
                                // Append keyframe time and keyframe/value delimiter (=).
-                               if ( item.frame - in != 0 )
-                               {
-                                       const char *s;
-                                       switch (item.keyframe_type) {
-                                       case mlt_keyframe_discrete:
-                                               s = "|";
-                                               break;
-                                       default:
-                                               s = "";
-                                               break;
-                                       }
-                                       sprintf( ret + used, "%d%s=", item.frame - in, s );
+                               const char *s;
+                               switch (item.keyframe_type) {
+                               case mlt_keyframe_discrete:
+                                       s = "|";
+                                       break;
+                               case mlt_keyframe_smooth:
+                                       s = "~";
+                                       break;
+                               default:
+                                       s = "";
+                                       break;
                                }
+                               sprintf( ret + used, "%d%s=", item.frame - in, s );
+
                                // Append item value.
                                if ( item.is_key )
                                        strcat( ret, mlt_property_get_string_l( item.property, self->locale ) );