better effects support with nested sequences

effects/effects.h

@@ -89,7 +89,10 @@ private:
     int prev_x;
     int prev_y;
     int prev_rot;
+    int perp_x;
+    int perp_y;
     double t;
+    bool inside;
 };
 
 class TextEffect : public Effect {

effects/shakeeffect.cpp

@@ -12,7 +12,7 @@
 #include "project/sequence.h"
 #include "panels/timeline.h"
 
-ShakeEffect::ShakeEffect(Clip *c) : Effect(c, EFFECT_TYPE_VIDEO, VIDEO_SHAKE_EFFECT) {
+ShakeEffect::ShakeEffect(Clip *c) : Effect(c, EFFECT_TYPE_VIDEO, VIDEO_SHAKE_EFFECT), inside(false) {
     ui_layout->addWidget(new QLabel("Intensity:"), 0, 0);
     intensity_val = new LabelSlider();
     intensity_val->set_minimum_value(0);
@@ -88,6 +88,22 @@ void ShakeEffect::process_gl(int*, int*) {
             prev_y = next_y;
             next_x = (qrand() % (int) (intensity_val->value() * 2)) - intensity_val->value();
             next_y = (qrand() % (int) (intensity_val->value() * 2)) - intensity_val->value();
+
+            // find perpendicular slope that passes through (mid_x, mid_y)
+            int mid_x = (prev_x + next_x) / 2;
+            int mid_y = (prev_y + next_y) / 2;
+            int slope_num = (next_y-prev_y);
+            if (slope_num > 0) {
+                int slope_den = (next_x-prev_x);
+                int add = (next_x-prev_x)/4;
+                if (inside) add = -add;
+                inside = !inside;
+                perp_x = mid_x + add;
+                perp_y = (-(slope_den / slope_num)) * perp_x + mid_y;
+            } else {
+                perp_x = mid_x;
+                perp_y = mid_y;
+            }
         } else {
             prev_x = 0;
             prev_y = 0;
@@ -106,10 +122,16 @@ void ShakeEffect::process_gl(int*, int*) {
         }
         shake_progress = 0;
     }
-    t = 1 - qPow(((double) shake_progress / (double) shake_limit)-1, 2);
-    offset_x = lerp(prev_x, next_x, t);
-    offset_y = lerp(prev_y, next_y, t);
+
+    t = (double) shake_progress / (double) shake_limit;
+
+    double oneminust = 1 - t;
+
+    offset_x = (qPow(oneminust, 2)*prev_x) + (2*oneminust*t*perp_x) + (qPow(t, 2) * next_x);
+    offset_y = (qPow(oneminust, 2)*prev_y) + (2*oneminust*t*perp_y) + (qPow(t, 2) * next_y);
+
     offset_rot = lerp(prev_rot, next_rot, t);
+
     glTranslatef(offset_x, offset_y, 0);
     glRotatef(offset_rot, 0, 0, 1);
     shake_progress++;

mainwindow.cpp

@@ -140,7 +140,7 @@ MainWindow::~MainWindow() {
     QString data_dir = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation);
     if (!data_dir.isEmpty() && !autorecovery_filename.isEmpty()) {
         if (QFile::exists(autorecovery_filename)) {
-            QFile::remove(autorecovery_filename);
+            QFile::rename(autorecovery_filename, autorecovery_filename + "." + QDateTime::currentDateTimeUtc().toString("yyyyMMddHHmmss"));
         }
     }
     if (!config_dir.isEmpty()) {

playback/cacher.cpp

@@ -46,7 +46,11 @@ void cache_audio_worker(Clip* c, Clip* nest) {
             // no more audio left in frame, get a new one
             if (!c->reached_end) {
                 retrieve_next_frame_raw_data(c, frame);
-                apply_audio_effects(c, frame, av_samples_get_buffer_size(NULL, frame->channels, frame->nb_samples, static_cast<AVSampleFormat>(frame->format), 1));
+                int byte_count = av_samples_get_buffer_size(NULL, frame->channels, frame->nb_samples, static_cast<AVSampleFormat>(frame->format), 1);
+                apply_audio_effects(c, frame, byte_count);
+                if (nest != NULL) {
+                    apply_audio_effects(nest, frame, byte_count);
+                }
             } else {
                 // set by retrieve_next_frame_raw_data indicating no more frames in file,
                 // but there still may be samples in swresample

project/clip.cpp

@@ -131,6 +131,12 @@ void Clip::run_video_pre_effect_stack(long playhead, int* anchor_x, int* anchor_
     }
 }
 
+void Clip::run_video_post_effect_stack() {
+    for (int j=0;j<effects.size();j++) {
+        if (effects.at(j)->is_enabled()) effects.at(j)->post_gl();
+    }
+}
+
 Clip::~Clip() {
     if (open) {
 		close_clip(this);

project/clip.h

@@ -43,6 +43,7 @@ struct Clip
 	void reset();
     void refresh();
     void run_video_pre_effect_stack(long playhead, int *anchor_x, int *anchor_y);
+    void run_video_post_effect_stack();
 
 	// timeline variables
     Sequence* sequence;

ui/viewerwidget.cpp

@@ -204,9 +204,7 @@ void ViewerWidget::compose_sequence(Clip* nest, bool render_audio) {
                         c->texture->release();
 
                         // perform all transform effects
-                        for (int j=0;j<c->effects.size();j++) {
-                            if (c->effects.at(j)->is_enabled()) c->effects.at(j)->post_gl();
-                        }
+                        c->run_video_post_effect_stack();
                     }
                 } else if (render_audio &&
                            c->stream->codecpar->codec_type == AVMEDIA_TYPE_AUDIO &&
@@ -218,6 +216,7 @@ void ViewerWidget::compose_sequence(Clip* nest, bool render_audio) {
                 break;
             case MEDIA_TYPE_SEQUENCE:
                 compose_sequence(c, render_audio);
+                c->run_video_post_effect_stack();
                 break;
             }
         }