New function that resets screenshot index to 0. Usefull when capturing png sequence for video

apps/OpenSpace/main.cpp

@@ -879,6 +879,10 @@ void setSgctDelegateFunctions() {
         Engine::instance().takeScreenshot(std::move(windowIds));
         return Engine::instance().screenShotNumber();
     };
+    sgctDelegate.resetScreenshotNumber = []() {
+        ZoneScoped;
+        Engine::instance().resetScreenshotNumber();
+    };
     sgctDelegate.swapBuffer = []() {
         ZoneScoped;
 

include/openspace/engine/windowdelegate.h

@@ -81,6 +81,8 @@ struct WindowDelegate {
     unsigned int (*takeScreenshot)(bool applyWarping, std::vector<int> windowIds) =
         [](bool, std::vector<int>) { return 0u; };
 
+    void (*resetScreenshotNumber)() = []() {};
+
     void (*swapBuffer)() = []() {};
 
     int (*nWindows)() = []() { return 0; };

include/openspace/rendering/renderengine.h

@@ -135,6 +135,11 @@ public:
      */
     void takeScreenshot();
 
+    /**
+     * Resets the screenshot index to 0
+     */
+    void resetScreenshotNumber();
+
     /**
      * Get the filename of the latest screenshot
      */

src/rendering/renderengine.cpp

@@ -1027,6 +1027,14 @@ void RenderEngine::takeScreenshot() {
     );
 }
 
+/**
+ * Resets the screenshot index to 0
+ */
+void RenderEngine::resetScreenshotNumber() {
+    _latestScreenshotNumber = 0;
+    global::windowDelegate->resetScreenshotNumber();
+}
+
 unsigned int RenderEngine::latestScreenshotNumber() const {
     return _latestScreenshotNumber;
 }
@@ -1038,7 +1046,8 @@ scripting::LuaLibrary RenderEngine::luaLibrary() {
             codegen::lua::AddScreenSpaceRenderable,
             codegen::lua::RemoveScreenSpaceRenderable,
             codegen::lua::TakeScreenshot,
-            codegen::lua::DpiScaling
+            codegen::lua::DpiScaling,
+            codegen::lua::ResetScreenshotNumber
         }
     };
 }

src/rendering/renderengine_lua.inl

@@ -67,6 +67,14 @@ namespace {
     return static_cast<int>(screenshotNumber);
 }
 
+/**
+* Reset screenshot index to 0.
+*/
+[[codegen::luawrap]] void resetScreenshotNumber() {
+    using namespace openspace;
+    global::renderEngine->resetScreenshotNumber();
+}
+
 // Extracts the DPI scaling for either the GUI window or if there is no dedicated GUI
 // window, the first window.
 [[codegen::luawrap]] float dpiScaling() {