Capture image testing

- New image_test subdir in testing dir
  - Top-level script invoked by batch harness
  - Script to be executed in HdRemix app
  - Common image + general testing python methods, can be used by other tests in future
- Add image testing phase to capture tests
  - Open verified capture in HdRemix application, take screenshot, compare against golden
- Workaround headless machine problem
- [REMIX-2344] [REMIX-2345] [REMIX-2346] [REMIX-2347] [REMIX-2348] [REMIX-2865]

src/dxvk/rtx_render/rtx_context.cpp

@@ -166,6 +166,7 @@ namespace dxvk {
       m_screenshotFrameNum = stoul(env::getEnvVar("DXVK_DUMP_SCREENSHOT_FRAME"));
       m_screenshotFrameEnabled = true;
     }
+
     if (env::getEnvVar("DXVK_TERMINATE_APP_FRAME") != "") {
       m_terminateAppFrameNum = stoul(env::getEnvVar("DXVK_TERMINATE_APP_FRAME"));
       m_triggerDelayedTerminate = true;

src/dxvk/rtx_render/rtx_game_capturer.cpp

@@ -134,7 +134,9 @@ namespace dxvk {
     , m_sceneManager(sceneManager)
     , m_exporter(exporter)
     , m_options{ getOptions() } {
-    Logger::info(str::format("[GameCapturer] DXVK_RTX_CAPTURE_ENABLE_ON_FRAME: ", env::getEnvVar("DXVK_RTX_CAPTURE_ENABLE_ON_FRAME")));
+    if(!env::getEnvVar("DXVK_RTX_CAPTURE_ENABLE_ON_FRAME").empty()) {
+      Logger::info(str::format("[GameCapturer] DXVK_RTX_CAPTURE_ENABLE_ON_FRAME: ", env::getEnvVar("DXVK_RTX_CAPTURE_ENABLE_ON_FRAME")));
+    }
     env::createDirectory(BASE_DIR);
     env::createDirectory(BASE_DIR + lss::commonDirName::texDir);
     env::createDirectory(BASE_DIR + lss::commonDirName::matDir);