From: David Gow <david@ingeniumdigital.com>
Date: Sun, 27 Apr 2014 13:59:06 +0000 (+0800)
Subject: Add GPU performance queries.
X-Git-Url: https://git.ucc.asn.au/?a=commitdiff_plain;h=6229c121e63cf53459cf82cb1eaa8af063da592a;p=ipdf%2Fcode.git

Add GPU performance queries.
---

diff --git a/bin/ipdf b/bin/ipdf
index 29d876f..a39e28c 100755
Binary files a/bin/ipdf and b/bin/ipdf differ
diff --git a/src/main.h b/src/main.h
index e6100ed..6821399 100644
--- a/src/main.h
+++ b/src/main.h
@@ -70,7 +70,8 @@ inline void MainLoop(Document & doc, const Rect & bounds = Rect(0,0,1,1), const
 	{
 		scr.Clear();
 		view.Render(scr.ViewportWidth(), scr.ViewportHeight());
-		scr.DebugFontPrintF("[CPU] Render took %lf ms (%lf FPS)\n", (SDL_GetPerformanceCounter() - init_time)* 1000.0/SDL_GetPerformanceFrequency(), SDL_GetPerformanceFrequency()/(SDL_GetPerformanceCounter() - init_time));
+		scr.DebugFontPrintF("[CPU] Render took %lf ms (%lf FPS)\n", (scr.GetLastFrameTimeCPU())* 1000.0, 1.0/scr.GetLastFrameTimeCPU());
+		scr.DebugFontPrintF("[GPU] Render took %lf ms (%lf FPS)\n", (scr.GetLastFrameTimeGPU())* 1000.0, 1.0/scr.GetLastFrameTimeGPU());
 		scr.DebugFontPrintF("View bounds: %s\n", view.GetBounds().Str().c_str());
 		if (view.UsingGPUTransform())
 		{
diff --git a/src/screen.cpp b/src/screen.cpp
index 40754b3..9687c55 100644
--- a/src/screen.cpp
+++ b/src/screen.cpp
@@ -94,6 +94,12 @@ Screen::Screen()
 		Fatal("Your system does not support the ARB_explicit_attrib_location extension, which is required.");
 	}
 
+	m_frame_begin_time = SDL_GetPerformanceCounter();
+	m_last_frame_time = 0;
+	m_last_frame_gpu_timer = 0;
+	glGenQueries(1, &m_frame_gpu_timer);
+	glBeginQuery(GL_TIME_ELAPSED, m_frame_gpu_timer);
+
 	glDebugMessageCallback(opengl_debug_callback, 0);
 
 	GLuint default_vao;
@@ -230,7 +236,24 @@ void Screen::Present()
 {
 	if (m_debug_font_atlas)
 		DebugFontFlush();
+	m_last_frame_time = SDL_GetPerformanceCounter() - m_frame_begin_time;
+	glEndQuery(GL_TIME_ELAPSED);
 	SDL_GL_SwapWindow(m_window);
+	m_frame_begin_time = SDL_GetPerformanceCounter();
+	if (m_last_frame_gpu_timer)
+		glDeleteQueries(1, &m_last_frame_gpu_timer);
+	m_last_frame_gpu_timer = m_frame_gpu_timer;
+	glGenQueries(1, &m_frame_gpu_timer);
+	glBeginQuery(GL_TIME_ELAPSED, m_frame_gpu_timer);
+}
+
+double Screen::GetLastFrameTimeGPU() const
+{
+	if (!m_last_frame_gpu_timer)
+		return 0;
+	uint64_t frame_time_ns;
+	glGetQueryObjectui64v(m_last_frame_gpu_timer, GL_QUERY_RESULT, &frame_time_ns);
+	return frame_time_ns/1000000000.0;
 }
 
 void Screen::ScreenShot(const char * filename) const
diff --git a/src/screen.h b/src/screen.h
index d918dd1..f66c7aa 100644
--- a/src/screen.h
+++ b/src/screen.h
@@ -59,6 +59,11 @@ namespace IPDF
 
 		void ScreenShot(const char * filename) const;
 		void RenderBMP(const char * filename) const;
+
+		// Returns the CPU time (in seconds) it took to render the last completed frame.
+		double GetLastFrameTimeCPU() const { return m_last_frame_time / SDL_GetPerformanceFrequency(); }
+		// Returns the GPU time (in seconds) it took to render the last completed frame.
+		double GetLastFrameTimeGPU() const;
 	private:
 		void ResizeViewport(int width, int height);
 		void DebugFontFlush();
@@ -67,6 +72,11 @@ namespace IPDF
 		int m_last_mouse_x;
 		int m_last_mouse_y;
 
+		double m_last_frame_time;
+		double m_frame_begin_time;
+		GLuint m_frame_gpu_timer;
+		GLuint m_last_frame_gpu_timer;
+
 		int m_viewport_width;
 		int m_viewport_height;
 		SDL_Window *m_window;