Use > to slide faster, < to slow down (#77)

* sliding_step_factor

* reset window offset on H/L

* remove debug code

* readme

Author: fenollp

README.md

@@ -31,6 +31,7 @@ The actual file being represented below [is data/BigPictureBG.tga](http://www.do
 # Press F for full screen
 # Use the arrows to slide and enlarge the sliding window
 # Press M to slide the window to the end
+# Use > to slide faster, < to slow down
 # SPACE to toggle spinning the shape
 # Press O to reset the camera position
 # ESC to quit

src/Scene3D.cc

@@ -124,6 +124,16 @@ Scene3D::update(std::shared_ptr<Manager> manager, float elapsedTime) {
         manager->args()->spin_shape = !manager->args()->spin_shape;
     if (events->keyPressed('M'))
         manager->args()->move_window = !manager->args()->move_window;
+    if (events->keyPressed('.')) { // '>'
+        manager->args()->sliding_step_factor *= 2;
+    }
+    if (events->keyPressed(',')) { // '<'
+        manager->args()->sliding_step_factor /= 2;
+        if (manager->args()->sliding_step_factor == 0) {
+            manager->args()->sliding_step_factor = 1;
+        }
+    }
+
     if (manager->args()->move_window || selected_.size() == 0 || manager->slide_window()) {
         if (manager->args()->move_window)
             manager->slide_window_right();

src/include/Arguments.hh

@@ -13,7 +13,7 @@ struct Arguments {
           range_begin(0), range_end(0),
           fullscreen(false),
           keep_chrome(false),
-          sliding_window_length(37*1024), sliding_step(1024), move_window(false),
+          sliding_window_length(37*1024), sliding_step(1024), sliding_step_factor(1), move_window(false),
           spin_shape(true)
         {}
 
@@ -29,6 +29,7 @@ struct Arguments {
     bool keep_chrome;
     size_t sliding_window_length;
     size_t sliding_step;
+    size_t sliding_step_factor;
     bool move_window;
     bool spin_shape;
 };

src/include/Manager.hh

@@ -27,20 +27,24 @@ public:
 
     bool loadFile(size_t index);
     void loadFile(const std::string& filename);
-    void loadNextFile() { loadFile((fileIndex_ + 1) % args_->paths.size()); }
-    void loadPrevFile() { loadFile((fileIndex_ - 1) % args_->paths.size()); }
+    void loadNextFile() { loadFile((fileIndex_ + 1) % args_->paths.size()); reset_window(); }
+    void loadPrevFile() { loadFile((fileIndex_ - 1) % args_->paths.size()); reset_window(); }
 
     virtual void toggleFullscreen() = 0;
 
     std::shared_ptr<Arguments> args() const { return args_; }
     std::shared_ptr<Scene> scene() const { return scene_; }
 
+    void reset_window() { sliding_window_offset_ = 0; }
+
     void slide_window_left() {
         sliding_window_offset_ = (sliding_window_offset_ > args_->sliding_step)
-            ? sliding_window_offset_ - args_->sliding_step
+            ? sliding_window_offset_ - args_->sliding_step_factor * args_->sliding_step
             : 0;
     }
-    void slide_window_right() { sliding_window_offset_ += args_->sliding_step; }
+    void slide_window_right() {
+        sliding_window_offset_ += args_->sliding_step_factor * args_->sliding_step;
+    }
     void slide_window_up() { sliding_window_length_ += args_->sliding_step; }
     void slide_window_down() {
         sliding_window_length_ = (sliding_window_length_ > args_->sliding_step)