Initial version of Profiler class.

src/CMakeLists.txt

@@ -22,6 +22,7 @@ set(Magnum_SRCS
     Framebuffer.cpp
     IndexedMesh.cpp
     Mesh.cpp
+    Profiler.cpp
     Query.cpp
     Renderbuffer.cpp
     Shader.cpp
@@ -46,6 +47,7 @@ set(Magnum_HEADERS
     IndexedMesh.h
     Magnum.h
     Mesh.h
+    Profiler.h
     Query.h
     Renderbuffer.h
     Shader.h

src/Profiler.cpp

@@ -0,0 +1,111 @@
+/*
+    Copyright © 2010, 2011, 2012 Vladimír Vondruš <mosra@centrum.cz>
+
+    This file is part of Magnum.
+
+    Magnum is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License version 3
+    only, as published by the Free Software Foundation.
+
+    Magnum is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+    GNU Lesser General Public License version 3 for more details.
+*/
+
+#include "Profiler.h"
+
+#include <algorithm>
+#include <numeric>
+#include <Utility/Debug.h>
+
+using namespace std;
+
+namespace Magnum {
+
+Profiler::Section Profiler::addSection(const string& name) {
+    CORRADE_ASSERT(!enabled, "Profiler: cannot add section when profiling is enabled", 0);
+    sections.push_back(name);
+    return sections.size()-1;
+}
+
+void Profiler::setMeasureDuration(size_t frames) {
+    CORRADE_ASSERT(!enabled, "Profiler: cannot set measure duration when profiling is enabled", );
+    measureDuration = frames;
+}
+
+void Profiler::enable() {
+    enabled = true;
+    frameData.assign(measureDuration*sections.size(), chrono::high_resolution_clock::duration::zero());
+    totalData.assign(sections.size(), chrono::high_resolution_clock::duration::zero());
+    frameCount = 0;
+}
+
+void Profiler::disable() {
+    enabled = false;
+}
+
+void Profiler::start(Section section) {
+    if(!enabled) return;
+    CORRADE_ASSERT(section < sections.size(), "Profiler: unknown section passed to start()", );
+
+    save();
+
+    currentSection = section;
+}
+
+void Profiler::stop() {
+    if(!enabled) return;
+
+    save();
+
+    previousTime = chrono::high_resolution_clock::time_point();
+}
+
+void Profiler::save() {
+    auto now = chrono::high_resolution_clock::now();
+
+    /* If the profiler is already running, add time to given section */
+    if(previousTime != chrono::high_resolution_clock::time_point())
+        frameData[currentFrame*sections.size()+currentSection] += now-previousTime;
+
+    /* Set current time as previous for next section */
+    previousTime = now;
+}
+
+void Profiler::nextFrame() {
+    if(!enabled) return;
+
+    /* Next frame index */
+    size_t nextFrame = (currentFrame+1) % measureDuration;
+
+    /* Add times of current frame to total */
+    for(size_t i = 0; i != sections.size(); ++i)
+        totalData[i] += frameData[currentFrame*sections.size()+i];
+
+    /* Subtract times of next frame from total and erase them */
+    for(size_t i = 0; i != sections.size(); ++i) {
+        totalData[i] -= frameData[nextFrame*sections.size()+i];
+        frameData[nextFrame*sections.size()+i] = chrono::high_resolution_clock::duration::zero();
+    }
+
+    /* Advance to next frame */
+    currentFrame = nextFrame;
+
+    if(frameCount < measureDuration) ++frameCount;
+}
+
+void Profiler::printStatistics() {
+    if(!enabled) return;
+
+    vector<size_t> totalSorted(sections.size());
+    iota(totalSorted.begin(), totalSorted.end(), 0);
+
+    sort(totalSorted.begin(), totalSorted.end(), [this](size_t i, size_t j){return totalData[i] > totalData[j];});
+
+    Corrade::Utility::Debug() << "Statistics for last" << measureDuration << "frames:";
+    for(size_t i = 0; i != sections.size(); ++i)
+        Corrade::Utility::Debug() << ' ' << sections[totalSorted[i]] << chrono::microseconds(totalData[totalSorted[i]]).count()/frameCount << u8"µs";
+}
+
+}

src/Profiler.h

@@ -0,0 +1,206 @@
+#ifndef Magnum_Profiler_h
+#define Magnum_Profiler_h
+/*
+    Copyright © 2010, 2011, 2012 Vladimír Vondruš <mosra@centrum.cz>
+
+    This file is part of Magnum.
+
+    Magnum is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License version 3
+    only, as published by the Free Software Foundation.
+
+    Magnum is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+    GNU Lesser General Public License version 3 for more details.
+*/
+
+/** @file
+ * @brief Class Profiler
+ */
+
+#include <chrono>
+#include <initializer_list>
+#include <string>
+#include <vector>
+
+#include "magnumVisibility.h"
+
+namespace Magnum {
+
+/**
+@brief Measuring elapsed time in each frame
+
+Measures time passed during specified sections of each frame. It's meant to be
+used in rendering and event loops (e.g. Contexts::GlutContext::drawEvent()),
+but it's possible to use it standalone elsewhere. Example usage:
+@code
+Profiler p;
+
+// Register named sections
+struct {
+    Profiler::Section ai, physics, draw, bufferSwap;
+} sections;
+sections.ai = p.addSection("AI");
+sections.physics = p.addSection("Physics");
+sections.draw = p.addSection("Drawing");
+sections.bufferSwap = p.addSection("Buffer swap");
+
+// Enable profiling
+p.enable();
+
+// Mark sections in draw function
+void MyContext::drawEvent() {
+    p.start();
+
+    // ... misc stuff belogning to "Other" section
+
+    p.start(sections.ai);
+
+    // ... AI computation
+
+    p.start(sections.physics);
+
+    // ... physics simulation
+
+    p.start(sections.draw);
+
+    scene.draw()
+
+    p.start(sections.bufferSwap);
+
+    swapBuffers();
+
+    // Count everything before next call to drawEvent() into "Other" section
+    p.start();
+
+    // Mark start of next frame
+    p.nextFrame();
+}
+
+// Print statistics to debug output, showing how much time each section took
+p.printStatistics();
+@endcode
+
+It's possible to start profiler only for certain parts of the code and then
+stop it again using stop(), if you are not interested in profiling the rest.
+
+@todo Some unit testing
+@todo More time intervals
+*/
+class MAGNUM_EXPORT Profiler {
+    public:
+        /**
+         * @brief Section ID
+         *
+         * @see otherSection, addSection(), start(Section)
+         */
+        typedef unsigned int Section;
+
+        /**
+         * @brief Default section
+         *
+         * @see start()
+         */
+        static const Section otherSection = 0;
+
+        #ifndef DOXYGEN_GENERATING_OUTPUT
+        Profiler(): enabled(false), measureDuration(60), currentFrame(0), frameCount(0), sections{"Other"}, currentSection(otherSection) {}
+        #endif
+
+        /**
+         * @brief Set measure duration
+         *
+         * Measured data are averaged through given frame count. Default value
+         * is 60.
+         * @attention This function cannot be called if profiling is enabled.
+         */
+        void setMeasureDuration(size_t frames);
+
+        /**
+         * @brief Add named section
+         *
+         * @attention This function cannot be called if profiling is enabled.
+         * @see otherSection, start(Section), stop()
+         */
+        Section addSection(const std::string& name);
+
+        /**
+         * @brief Whether profiling is enabled
+         *
+         * If the profiling is not enabled, calls to start() and stop() have
+         * no effect.
+         */
+        bool isEnabled() { return enabled; }
+
+        /**
+         * @brief Enable profiling
+         *
+         * Clears already mesaured data.
+         * @see disable(), isEnabled()
+         */
+        void enable();
+
+        /**
+         * @brief Disable profiling
+         *
+         * @see enable(), isEnabled()
+         */
+        void disable();
+
+        /**
+         * @brief Start profiling of given named section
+         *
+         * If profiling is already running, current time is saved for previous
+         * section.
+         * @see @ref otherSection, start(Section)
+         */
+        void start(Section section);
+
+        /**
+         * @brief Start profiling of "other" section
+         *
+         * Same as calling `start(Profiler::otherSection)`.
+         * @note Does nothing if profiling is disabled.
+         */
+        inline void start() { start(otherSection); }
+
+        /**
+         * @brief Stop profiling
+         *
+         * Current time is saved for previous section.
+         * @note Does nothing if profiling is disabled.
+         */
+        void stop();
+
+        /**
+         * @brief Save data from previous frame and advance to another
+         *
+         * Call at the end of each frame.
+         * @note Does nothing if profiling is disabled.
+         */
+        void nextFrame();
+
+        /**
+         * @brief Print statistics
+         *
+         * Prints statistics about previous frame ordered by duration.
+         * @note Does nothing if profiling is disabled.
+         */
+        void printStatistics();
+
+    private:
+        void save();
+
+        bool enabled;
+        size_t measureDuration, currentFrame, frameCount;
+        std::vector<std::string> sections;
+        std::vector<std::chrono::high_resolution_clock::duration> frameData;
+        std::vector<std::chrono::high_resolution_clock::duration> totalData;
+        std::chrono::high_resolution_clock::time_point previousTime;
+        Section currentSection;
+};
+
+}
+
+#endif