CRM64Pro GDK v0.14.0
A free cross-platform game development kit built on top of SDL 3.0
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Description

Timer interface for timing control, frame rates and micro-benchmarking [v26.01.0].

Overview

The Timer interface manages all timing-related functionality including timer control, Render Frame Rate, Logic Frame Rate and micro-benchmarks. The Timer must be initiated with Timer::init().
One of the most important features is the fixed virtual logic frame rate with interpolation, which is implemented in this interface and in Main::update() method.

Key features

  • Timer control: Core timing management for application execution
  • Render Frame Rate (RFR): Asynchronous rendering rate control
  • Logic Frame Rate (LFR): Synchronous logic execution rate control
  • Micro-benchmarking: Statistical analysis of code snippet performance
  • Fixed virtual logic frame rate: Interpolation support for smooth gameplay

Frame rate types

By default, no preferred Render and Logic Frame Rate are set (both equal to 0). Use setRate() to configure specific values. Rates can be throttled down, but upper limits are imposed by the underlying hardware and ConfigMgr::iMTFriendly value.

Render Frame Rate (RFR)Asynchronous rate that does not stop your main loop. Renders all enabled and visible screens at the preferred rate. This rate is not guaranteed as some render frames may be dropped to maintain stable LFR. When vsync is enabled, set RFR to 0 for smoothest output
Logic Frame Rate (LFR)Synchronous rate that slows down your main loop to accommodate this rate. Under normal conditions (hardware can execute at preferred ratio), this rate remains quite stable

Micro-benchmarking system

The micro-benchmarking system measures small code snippets, capturing execution time and calculating statistical analysis on those measurements. It supports both latency and throughput benchmarks.



Benchmark metric types

BM_LATENCYMeasures execution time (lower is better). Results in units like ms, ns, μs. Default type.
BM_THROUGHPUTMeasures work per unit time (higher is better). Requires workAmount in benchStop(). Results in units like MB/s, ops/s, GB/s.


Thread safety
Although the system is not fully thread-safe, it can be made thread-safe by following these steps:

  1. Create micro-benchmarks on the same thread (usually main)
  2. Use each benchmark on different threads
  3. Close benchmarks from the same thread where they were created

Benchmark workflow

benchCreate()Create a named benchmark with estimated run count, unit, and metric type
benchStart()Start a measurement cycle
benchStop()Stop the current measurement cycle and optionally record work amount (for throughput benchmarks)
benchStats()Retrieve statistical results into a Timer::Stats structure
benchInfo()Display benchmark statistics to the default log
benchInfoEx()Generate interactive HTML report with charts and statistics
benchClose()Close the benchmark and release resources

Usage examples

Deterministic function testing
Testing a function with a known number of iterations:

Main &mC64 = Main::Instance();
Timer::Stats myStats;
Sint32 iRuns = 1000;
Sint32 idBench = mC64.ITimer().benchCreate("myBench", iRuns);
for(Sint32 i = 0; i < iRuns; ++i)
{
mC64.ITimer().benchStart(idBench);
func_to_be_tested();
mC64.ITimer().benchStop(idBench);
}
mC64.ITimer().benchStats(idBench, myStats);
// Optionally call mC64.ITimer().benchInfo(idBench) to display stats via the default log
mC64.ITimer().benchClose(idBench);
static Main & Instance()
Access the Main singleton.
Definition CoreMain.cpp:361


Application behavior profiling
Measuring logic and render performance throughout application lifetime:

Main &mC64 = Main::Instance();
Sint32 iRuns = 10000; // Estimation; more will be allocated if needed
Sint32 idBenchL = mC64.ITimer().benchCreate("myBench-Logic", iRuns);
Sint32 idBenchR = mC64.ITimer().benchCreate("myBench-Render", iRuns);
while(iDone == 0)
{
// Logic stuff
mC64.ITimer().benchStart(idBenchL);
...
mC64.ITimer().benchStop(idBenchL);
// Render stuff
mC64.ITimer().benchStart(idBenchR);
...
mC64.ITimer().benchStop(idBenchR);
}
mC64.ITimer().info(); // Displays all benchmarks stats
mC64.ITimer().benchClose(idBenchL);
mC64.ITimer().benchClose(idBenchR);


Throughput benchmark (file I/O)
Measuring data processing throughput in MB/s:

Main &mC64 = Main::Instance();
Sint32 iRuns = 100;
Sint32 idBench = mC64.ITimer().benchCreate("FileRead", iRuns, "MB/s", Timer::BM_THROUGHPUT);
for(Sint32 i = 0; i < iRuns; ++i)
{
mC64.ITimer().benchStart(idBench);
size_t bytes = ReadDataFromFile(); // Returns bytes read
mC64.ITimer().benchStop(idBench, bytes / (1024 * 1024)); // Convert bytes to MB
}
mC64.ITimer().benchInfo(idBench); // Shows average MB/s, fastest, slowest, etc.
mC64.ITimer().benchClose(idBench);
@ BM_THROUGHPUT
Higher is better (e.g., ops/s, MB/s).
Definition CRM64Pro.h:1841


Throughput benchmark (operations)
Measuring computational throughput in operations/second:

Main &mC64 = Main::Instance();
Sint32 idBench = mC64.ITimer().benchCreate("HashOps", 1000, "ops/s", Timer::BM_THROUGHPUT);
for(Sint32 i = 0; i < 1000; ++i)
{
mC64.ITimer().benchStart(idBench);
Sint32 count = CalculateHashes(); // May calculate multiple hashes per iteration
mC64.ITimer().benchStop(idBench, count); // Record number of operations
}
mC64.ITimer().benchInfoEx(idBench, "Hash Performance"); // Generate HTML report
mC64.ITimer().benchClose(idBench);

Best practices

  • Always call Timer::init() before using any timer functionality
  • Use setRate() to configure specific RFR and LFR values based on your application needs
  • Set RFR to 0 when vsync is enabled for the smoothest rendering output
  • Keep in mind that RFR applies to all enabled and visible screens
  • For micro-benchmarks, provide a reasonable estimation of run count to minimize reallocations
  • For LATENCY benchmarks: use appropriate time units (ms, ns, μs) based on expected execution time
  • For THROUGHPUT benchmarks: always pass workAmount to benchStop() in consistent units matching the metric
  • When comparing benchmarks in benchInfoEx(), ensure all have the same unit and metric type
  • Create and close benchmarks on the same thread to ensure thread safety
  • Access the interface exclusively through Main::ITimer()
Note
The Timer interface is a singleton, automatically created once Main is instantiated. You can get a reference to this interface using Main::ITimer() method.
The Timer interface is automatically released when Main::Terminate() is called. At this time, any resource still loaded will be released, avoiding resource leaks.

Classes

class  CRM64Pro::Timer
 Timer class. More...

Enumerations

enum  CRM64Pro::eTimerState { CRM64Pro::TS_INIT = 0 , CRM64Pro::TS_RESET = 1 }
 Timer init state. More...

Functions

bool CRM64Pro::Timer::info (Sint32 iMode=0) override
 Request Timer Interface information.
bool CRM64Pro::Timer::init (eTimerState tsOpt=TS_INIT)
 Initialize the timer system.
bool CRM64Pro::Timer::setRate (Uint16 iR, Uint16 iL)
 Set preferred Render and Logic Frame Rate.
Sint32 CRM64Pro::Timer::getLFR () const
 Get the preferred Logic Frame Rate.
Sint32 CRM64Pro::Timer::getRFR () const
 Get the preferred Render Frame Rate.
float CRM64Pro::Timer::getAverageRFR () const
 Get the average Render Frame Rate since the last timer init or reset.
float CRM64Pro::Timer::getAverageLFR () const
 Get the average Logic Frame Rate since the last timer init or reset.
Uint32 CRM64Pro::Timer::getCurrentRFR () const
 Get current Render Frame Rate during last recent second.
Uint32 CRM64Pro::Timer::getCurrentLFR () const
 Get current Logic Frame Rate during last recent second.
Uint32 CRM64Pro::Timer::getRenderFrames () const
 Get total render frames since the last timer init or reset.
Uint32 CRM64Pro::Timer::getLogicFrames () const
 Get total logic frames since the last timer init or reset.
float CRM64Pro::Timer::getTime () const
 Get the execution time (in seconds) since the last timer init or reset.
Uint64 CRM64Pro::Timer::getTicks ()
 Get the execution time (in milliseconds) since the last timer init or reset.
Uint64 CRM64Pro::Timer::getTicksNow ()
 Get the execution time (in milliseconds) since the last timer init or reset.
Uint64 CRM64Pro::Timer::getHiResTime ()
 Get the execution time (in nanoseconds) since the last timer init or reset.
Sint32 CRM64Pro::Timer::benchCreate (const string &sName, Sint32 iRuns=0, const string &sUnit="ms", eBenchMetric eMetric=BM_LATENCY)
 Create a microbenchmark.
bool CRM64Pro::Timer::benchStart (Sint32 idBench)
 Start a microbenchmark measurement cycle.
bool CRM64Pro::Timer::benchStop (Sint32 idBench, Uint64 workAmount=1)
 Stop a microbenchmark measurement cycle.
bool CRM64Pro::Timer::benchClose (Sint32 idBench)
 Close a microbenchmark.
bool CRM64Pro::Timer::benchStats (Sint32 idBench, Stats &stats)
 Calculate the statistical analysis given the current measurements.
bool CRM64Pro::Timer::benchInfo (Sint32 idBench)
 Display benchmark information to the default log.
bool CRM64Pro::Timer::benchInfoEx (Sint32 idBench, const string &sTitle="Report")
 Generate HTML benchmark report for a single benchmark.
bool CRM64Pro::Timer::benchInfoEx (const vector< Sint32 > &vBenchIds, const string &sTitle="Report")
 Generate HTML benchmark report for multiple benchmarks.

Enumeration Type Documentation

◆ eTimerState

Timer init state.

Enumerator
TS_INIT 

'tsOpt' parameter in Timer::init(), initializes or resets all timer settings.

TS_RESET 

'tsOpt' parameter in Timer::init(), only resets the timer if it was previously initialized keeping RFR and LFR rates.

Function Documentation

◆ info()

bool CRM64Pro::Timer::info ( Sint32 iMode = 0)
override

Request Timer Interface information.

Writes information to the default log.

Parameters
iMode-1 to display only manager information. 0 (default) to display manager and all objects. Specific object ID to display manager and only that object.
Returns
true on success or false on failure.

◆ init()

bool CRM64Pro::Timer::init ( eTimerState tsOpt = TS_INIT)

Initialize the timer system.

The first call to this method initializes the SDL timer subsystem.

Parameters
tsOptCheck ::eTimerState enum for further information. Default is TS_INIT.
Returns
true on success or false on failure.
Note
init(TS_RESET) is called internally by Main::cleanUp().

◆ setRate()

bool CRM64Pro::Timer::setRate ( Uint16 iR,
Uint16 iL )

Set preferred Render and Logic Frame Rate.

Parameters
iRpreferred Render Frame Rate. Default 0 means unlimited. Maximum value is 500.
iLpreferred Logic Frame Rate. Default 0 means unlimited. Maximum value is 20000.
Returns
true on success or false on failure.

◆ getLFR()

Sint32 CRM64Pro::Timer::getLFR ( ) const

Get the preferred Logic Frame Rate.

Returns
0 or positive value on success or -1 on failure.

◆ getRFR()

Sint32 CRM64Pro::Timer::getRFR ( ) const

Get the preferred Render Frame Rate.

Returns
0 or positive value on success or -1 on failure.

◆ getAverageRFR()

float CRM64Pro::Timer::getAverageRFR ( ) const

Get the average Render Frame Rate since the last timer init or reset.

Returns
0 or positive value on success or -1 on failure.

◆ getAverageLFR()

float CRM64Pro::Timer::getAverageLFR ( ) const

Get the average Logic Frame Rate since the last timer init or reset.

Returns
0 or positive value on success or -1 on failure.

◆ getCurrentRFR()

Uint32 CRM64Pro::Timer::getCurrentRFR ( ) const

Get current Render Frame Rate during last recent second.

Returns
Render Frame Rate.

◆ getCurrentLFR()

Uint32 CRM64Pro::Timer::getCurrentLFR ( ) const

Get current Logic Frame Rate during last recent second.

Returns
Logic Frame Rate.

◆ getRenderFrames()

Uint32 CRM64Pro::Timer::getRenderFrames ( ) const

Get total render frames since the last timer init or reset.

Returns
Total number of Render frames.

◆ getLogicFrames()

Uint32 CRM64Pro::Timer::getLogicFrames ( ) const

Get total logic frames since the last timer init or reset.

Returns
Total number of Logic frames.

◆ getTime()

float CRM64Pro::Timer::getTime ( ) const

Get the execution time (in seconds) since the last timer init or reset.

This time will be constant inside the same Logic Frame iteration and will be updated on Main::update() if a new Logic Frame must be produced.

Returns
0 or positive value on success or -1 on failure.

◆ getTicks()

Uint64 CRM64Pro::Timer::getTicks ( )

Get the execution time (in milliseconds) since the last timer init or reset.

This time will be constant inside the same Logic Frame iteration and will be updated on Main::update() if a new Logic Frame must be produced.

Returns
unsigned int 32bits with the milliseconds.

◆ getTicksNow()

Uint64 CRM64Pro::Timer::getTicksNow ( )

Get the execution time (in milliseconds) since the last timer init or reset.

This time will be exactly the "now" time, on other words, it is not linked anyway to the Logic Frame iteration.

Returns
unsigned int 32bits with the milliseconds.

◆ getHiResTime()

Uint64 CRM64Pro::Timer::getHiResTime ( )

Get the execution time (in nanoseconds) since the last timer init or reset.

This is the high resolution timer when you need more accurate time precision.

Returns
unsigned 64bits with the nanoseconds.

◆ benchCreate()

Sint32 CRM64Pro::Timer::benchCreate ( const string & sName,
Sint32 iRuns = 0,
const string & sUnit = "ms",
eBenchMetric eMetric = BM_LATENCY )

Create a microbenchmark.

Creates a named benchmark with an estimated number of measurement runs.

Parameters
sNamestring with the name of this benchmark.
iRunsestimated number of runs. Default 0 (automatically managed).
sUnitunit of measurement (e.g., "ms", "ns", "ops/s", "MB/s"). Default "ms".
eMetricmetric direction: BM_LATENCY (lower is better) or BM_THROUGHPUT (higher is better). Default BM_LATENCY.
Returns
greater than 0 on success (the Bench id) or a negative error code on failure.
Note
If a benchmark with the same name already exists, it returns the existing Bench id.

◆ benchStart()

bool CRM64Pro::Timer::benchStart ( Sint32 idBench)

Start a microbenchmark measurement cycle.

Parameters
idBenchBench id.
Returns
true on success or false on failure.
Note
Each benchStart() must be followed by a benchStop().

◆ benchStop()

bool CRM64Pro::Timer::benchStop ( Sint32 idBench,
Uint64 workAmount = 1 )

Stop a microbenchmark measurement cycle.

Stops the measurement and records the elapsed time. For throughput benchmarks, also records the amount of work completed to calculate throughput.

Parameters
idBenchBench id.
workAmountAmount of work completed during this measurement cycle. For LATENCY benchmarks: ignored (defaults to 1). For THROUGHPUT benchmarks: work done in the unit's base quantity (e.g., bytes for "MB/s", operations for "ops/s").
Returns
true on success or false on failure.
Note
Each benchStart() must be followed by a benchStop(). For LATENCY: stores elapsed time in the specified unit. For THROUGHPUT: calculates and stores throughput = workAmount / elapsed_time.

◆ benchClose()

bool CRM64Pro::Timer::benchClose ( Sint32 idBench)

Close a microbenchmark.

Frees the resources of the benchmark and its stats.

Parameters
idBenchBench id. Use -1 to close all benchmarks.
Returns
true on success or false on failure.

◆ benchStats()

bool CRM64Pro::Timer::benchStats ( Sint32 idBench,
Stats & stats )

Calculate the statistical analysis given the current measurements.

Parameters
idBenchBench id.
statsa Stats struct to be filled with current stats. The values are given in milliseconds.
Returns
true on success or false on failure.

◆ benchInfo()

bool CRM64Pro::Timer::benchInfo ( Sint32 idBench)

Display benchmark information to the default log.

Outputs the benchmark statistics to the default log.

Parameters
idBenchBench id.
Returns
true on success or false on failure.
Note
If statistics haven't been calculated yet, benchStats() will be called automatically.

◆ benchInfoEx() [1/2]

bool CRM64Pro::Timer::benchInfoEx ( Sint32 idBench,
const string & sTitle = "Report" )

Generate HTML benchmark report for a single benchmark.

Parameters
idBenchBench id.
sTitleReport title used in the HTML and filename. Default "Report".
Returns
true on success or false on failure.
Note
Unit and metric direction are read from the benchmark properties set during benchCreate(). Generates file: Microbench_{TITLE}_YYYYMMDD_HHMMSS.html in the current working directory.

◆ benchInfoEx() [2/2]

bool CRM64Pro::Timer::benchInfoEx ( const vector< Sint32 > & vBenchIds,
const string & sTitle = "Report" )

Generate HTML benchmark report for multiple benchmarks.

Parameters
vBenchIdsVector of Bench ids to include in the report.
sTitleReport title used in the HTML and filename. Default "Report".
Returns
true on success or false on failure.
Note
Unit and metric direction are read from the first benchmark in the vector. If other benchmarks have different units/metrics, a warning is logged but processing continues. The first benchmark in the vector is used as baseline for delta calculations. Generates file: Microbench_{TITLE}_YYYYMMDD_HHMMSS.html in the current working directory.