NLA SoC: Quick hack - Reversed playback

Animations can now be played back in reverse, by clicking on the reversed-playback button in the TimeLine header beside the play button (NEW ICON NEEDED HERE).

I'm not sure how well this works with sound, but from what I gather, this can be quite useful for animators to use.

source/blender/editors/include/ED_screen_types.h

@@ -33,6 +33,7 @@
 typedef struct ScreenAnimData {
 	ARegion *ar;	/* do not read from this, only for comparing if region exists */
 	int redraws;
+	int reverse;
 } ScreenAnimData;
 
 

source/blender/editors/screen/screen_edit.c

@@ -1460,7 +1460,9 @@ void ED_screen_full_prevspace(bContext *C)
 		ed_screen_fullarea(C, sa);
 }
 
-/* redraws: uses defines from stime->redraws */
+/* redraws: uses defines from stime->redraws 
+ * enable: 1 - forward on, -1 - backwards on, 0 - off
+ */
 void ED_screen_animation_timer(bContext *C, int redraws, int enable)
 {
 	bScreen *screen= CTX_wm_screen(C);
@@ -1477,6 +1479,7 @@ void ED_screen_animation_timer(bContext *C, int redraws, int enable)
 		screen->animtimer= WM_event_add_window_timer(win, TIMER0, (1.0/FPS));
 		sad->ar= CTX_wm_region(C);
 		sad->redraws= redraws;
+		sad->reverse= (enable < 0);
 		screen->animtimer->customdata= sad;
 		
 	}

source/blender/editors/screen/screen_ops.c

@@ -2067,19 +2067,40 @@ static int screen_animation_step(bContext *C, wmOperator *op, wmEvent *event)
 		
 		if(scene->audio.flag & AUDIO_SYNC) {
 			int step = floor(wt->duration * FPS);
-			scene->r.cfra += step;
+			if (sad->reverse) // XXX does this option work with audio?
+				scene->r.cfra -= step;
+			else
+				scene->r.cfra += step;
 			wt->duration -= ((float)step)/FPS;
 		}
-		else
-			scene->r.cfra++;
+		else {
+			if (sad->reverse)
+				scene->r.cfra--;
+			else
+				scene->r.cfra++;
+		}
 		
-		if (scene->r.psfra) {
-			if(scene->r.cfra > scene->r.pefra)
-				scene->r.cfra= scene->r.psfra;
+		if (sad->reverse) {
+			/* jump back to end */
+			if (scene->r.psfra) {
+				if(scene->r.cfra < scene->r.psfra)
+					scene->r.cfra= scene->r.pefra;
+			}
+			else {
+				if(scene->r.cfra < scene->r.sfra)
+					scene->r.cfra= scene->r.efra;
+			}
 		}
 		else {
-			if(scene->r.cfra > scene->r.efra)
-				scene->r.cfra= scene->r.sfra;
+			/* jump back to start */
+			if (scene->r.psfra) {
+				if(scene->r.cfra > scene->r.pefra)
+					scene->r.cfra= scene->r.psfra;
+			}
+			else {
+				if(scene->r.cfra > scene->r.efra)
+					scene->r.cfra= scene->r.sfra;
+			}
 		}
 
 		/* since we follow drawflags, we can't send notifier but tag regions ourselves */
@@ -2127,8 +2148,9 @@ static int screen_animation_play(bContext *C, wmOperator *op, wmEvent *event)
 		ED_screen_animation_timer(C, 0, 0);
 	}
 	else {
-		/* todo: RNA properties to define play types */
-		ED_screen_animation_timer(C, TIME_REGION|TIME_ALL_3D_WIN, 1);
+		int mode= (RNA_boolean_get(op->ptr, "reverse")) ? -1 : 1;
+		
+		ED_screen_animation_timer(C, TIME_REGION|TIME_ALL_3D_WIN, mode);
 		
 		if(screen->animtimer) {
 			wmTimer *wt= screen->animtimer;
@@ -2152,7 +2174,7 @@ void SCREEN_OT_animation_play(wmOperatorType *ot)
 	
 	ot->poll= ED_operator_screenactive;
 	
-	
+	RNA_def_boolean(ot->srna, "reverse", 0, "Play in Reverse", "Animation is played backwards");
 }
 
 /* ************** border select operator (template) ***************************** */

source/blender/editors/space_time/time_header.c

@@ -373,6 +373,7 @@ static uiBlock *time_framemenu(bContext *C, ARegion *ar, void *arg_unused)
 #define B_REDRAWALL		750
 #define B_TL_REW		751
 #define B_TL_PLAY		752
+#define B_TL_RPLAY		760
 #define B_TL_FF			753
 #define B_TL_PREVKEY	754
 #define B_TL_NEXTKEY	755
@@ -415,6 +416,18 @@ void do_time_buttons(bContext *C, void *arg, int event)
 				sad->ar= time_top_left_3dwindow(screen);
 			}
 			
+			break;
+		case B_TL_RPLAY:
+			ED_screen_animation_timer(C, stime->redraws, -1);
+			
+			/* update region if TIME_REGION was set, to leftmost 3d window */
+			if(screen->animtimer && (stime->redraws & TIME_REGION)) {
+				wmTimer *wt= screen->animtimer;
+				ScreenAnimData *sad= wt->customdata;
+				
+				sad->ar= time_top_left_3dwindow(screen);
+			}
+			
 			break;
 		case B_TL_STOP:
 			ED_screen_animation_timer(C, 0, 0);
@@ -553,14 +566,27 @@ void time_header_buttons(const bContext *C, ARegion *ar)
 				 xco, yco, XIC, YIC, 0, 0, 0, 0, 0, "Skip to previous keyframe (Ctrl PageDown)");
 	xco+= XIC+4;
 	
-	if(CTX_wm_screen(C)->animtimer)
+	if(CTX_wm_screen(C)->animtimer) {
+		/* pause button is drawn centered between the two other buttons for now (saves drawing 2 buttons, or having position changes) */
+		xco+= XIC/2 + 2;
+		
 		uiDefIconBut(block, BUT, B_TL_STOP, ICON_PAUSE,
 					 xco, yco, XIC, YIC, 0, 0, 0, 0, 0, "Stop Playing Timeline");
-	else 	   
+					 
+		xco+= XIC/2 + 2;
+	}
+	else {	   
+			// FIXME: the icon for this is crap
+		uiDefIconBut(block, BUT, B_TL_RPLAY, ICON_REW/*ICON_PLAY*/,
+					 xco, yco, XIC, YIC, 0, 0, 0, 0, 0, "Play Timeline in Reverse");
+					 
+		xco+= XIC+4;
+					 
 		uiDefIconBut(block, BUT, B_TL_PLAY, ICON_PLAY,
 					 xco, yco, XIC, YIC, 0, 0, 0, 0, 0, "Play Timeline ");
-	
+	}
 	xco+= XIC+4;
+	
 	uiDefIconBut(block, BUT, B_TL_NEXTKEY, ICON_NEXT_KEYFRAME,
 				 xco, yco, XIC, YIC, 0, 0, 0, 0, 0, "Skip to next keyframe (Ctrl PageUp)");
 	xco+= XIC+4;