From 107187a20ca16ef2139713655ca35455aa8876d8 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sun, 6 Feb 2022 00:07:35 -0500
Subject: [PATCH] GUI: add ability to play from cursor position

Shift-Enter or F7
---
 src/engine/engine.cpp | 16 ++++++++++++++--
 src/engine/engine.h   |  5 ++++-
 src/gui/gui.cpp       | 18 ++++++++++++++----
 src/gui/gui.h         |  2 +-
 4 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/src/engine/engine.cpp b/src/engine/engine.cpp
index 7e3d4a1db..d327e7f5f 100644
--- a/src/engine/engine.cpp
+++ b/src/engine/engine.cpp
@@ -4748,7 +4748,7 @@ void* DivEngine::getDispatchChanState(int ch) {
   return disCont[dispatchOfChan[ch]].dispatch->getChanState(dispatchChanOfChan[ch]);
 }
 
-void DivEngine::playSub(bool preserveDrift) {
+void DivEngine::playSub(bool preserveDrift, int goalRow) {
   reset();
   if (preserveDrift && curOrder==0) return;
   bool oldRepeatPattern=repeatPattern;
@@ -4774,8 +4774,13 @@ void DivEngine::playSub(bool preserveDrift) {
   while (curOrder<goal) {
     if (nextTick(preserveDrift)) break;
   }
+  int oldOrder=curOrder;
+  while (curRow<goalRow) {
+    if (nextTick(preserveDrift)) break;
+    if (oldOrder!=curOrder) break;
+  }
   for (int i=0; i<song.systemLen; i++) disCont[i].dispatch->setSkipRegisterWrites(false);
-  if (goal>0) {
+  if (goal>0 || goalRow>0) {
     for (int i=0; i<song.systemLen; i++) disCont[i].dispatch->forceIns();
   }
   repeatPattern=oldRepeatPattern;
@@ -4815,6 +4820,13 @@ void DivEngine::play() {
   isBusy.unlock();
 }
 
+void DivEngine::playToRow(int row) {
+  isBusy.lock();
+  freelance=false;
+  playSub(false,row);
+  isBusy.unlock();
+}
+
 void DivEngine::stop() {
   isBusy.lock();
   freelance=false;
diff --git a/src/engine/engine.h b/src/engine/engine.h
index 412405591..6c4e146fe 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -206,7 +206,7 @@ class DivEngine {
   void recalcChans();
   void renderSamples();
   void reset();
-  void playSub(bool preserveDrift);
+  void playSub(bool preserveDrift, int goalRow=0);
 
   bool loadDMF(unsigned char* file, size_t len);
   bool loadFur(unsigned char* file, size_t len);
@@ -285,6 +285,9 @@ class DivEngine {
     // play
     void play();
 
+    // play to row
+    void playToRow(int row);
+
     // stop
     void stop();
 
diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index d0e6e2d5d..bf7d2e0c4 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -4630,9 +4630,13 @@ void FurnaceGUI::doRedo() {
   redoHist.pop_back();
 }
 
-void FurnaceGUI::play() {
+void FurnaceGUI::play(int row) {
   e->walkSong(loopOrder,loopRow,loopEnd);
-  e->play();
+  if (row>0) {
+    e->playToRow(row);
+  } else {
+    e->play();
+  }
   curNibble=false;
   orderNibble=false;
   activeNotes.clear();
@@ -4726,7 +4730,9 @@ void FurnaceGUI::keyDown(SDL_Event& ev) {
       play();
       break;
     case SDLK_F7:
-      play();
+      if (!e->isPlaying()) {
+        play(cursor.y);
+      }
       break;
     case SDLK_F8:
       stop();
@@ -4755,7 +4761,11 @@ void FurnaceGUI::keyDown(SDL_Event& ev) {
       if (e->isPlaying()) {
         stop();
       } else {
-        play();
+        if (ev.key.keysym.mod&KMOD_SHIFT) {
+          play(cursor.y);
+        } else {
+          play();
+        }
       }
       break;
   }
diff --git a/src/gui/gui.h b/src/gui/gui.h
index e16b26ac0..57c747171 100644
--- a/src/gui/gui.h
+++ b/src/gui/gui.h
@@ -383,7 +383,7 @@ class FurnaceGUI {
   void doUndo();
   void doRedo();
 
-  void play();
+  void play(int row=0);
   void stop();
 
   void previewNote(int refChan, int note);