Add high performance rendering mode which does not render the GUI every frame

src/main/java/eu/crushedpixel/replaymod/gui/GuiRenderSettings.java

@@ -516,6 +516,10 @@ public class GuiRenderSettings extends GuiScreen {
 
         options.setIgnoreCameraRotation(ignoreCamDir.isChecked());
 
+        if (isCtrlKeyDown()) {
+            options.setHighPerformance(true);
+        }
+
         if(commandInput.getText().trim().length() > 0) {
             options.setExportCommand(commandInput.getText().trim());
         }

src/main/java/eu/crushedpixel/replaymod/settings/RenderOptions.java

@@ -27,6 +27,7 @@ public final class RenderOptions {
     private int height = Minecraft.getMinecraft().displayHeight;
 
     // Highly advanced
+    private boolean highPerformance;
     private String exportCommand = "ffmpeg";
     private String exportCommandArgs = "";
 
@@ -55,6 +56,7 @@ public final class RenderOptions {
         copy.skyColor = this.skyColor;
         copy.width = this.width;
         copy.height = this.height;
+        copy.highPerformance = this.highPerformance;
         copy.exportCommand = this.exportCommand;
         copy.exportCommandArgs = this.exportCommandArgs;
         return copy;

src/main/java/eu/crushedpixel/replaymod/video/VideoRenderer.java

@@ -115,7 +115,9 @@ public class VideoRenderer implements RenderInfo {
 
     @Override
     public float updateForNextFrame() {
+        if (!options.isHighPerformance() || framesDone % fps == 0) {
             drawGui();
+        }
 
         updateTime(mc.timer, framesDone);