C++: Reflect recent gorays changes

[t-mat]

There are trivial changes. Basically aim to the same result as Go's.

Note: I didn't implement fixed output to 'render.ppm'. I think filename fixing is not a good idea. Because it is not convenient for running multiple languages from same directory.

[kidoman]

I am thinking of automating the running benchmark business using something like Jenkins. Since we will never be running two of these benchmarks together on the same node, having one single name (which can be captured as artifact, to visually verify the run) will make:

• invoking the benchmark simple (we can stick to the 3 simple command line arguments)
• a generic job to run any of the language benchmarks

What do you think?

[t-mat]

I prefer to specify output filename :

go run main.go -mp=4 -output=gorays-4mpix.ppm

"render.ppm" as default filename is okay. But hard coded / completely fixed output filename seems too much strict.

[kidoman]

I wanted to use the "flag" library in Go. But is such a possibility equally trivial in other languages/frameworks?

Then I agree, we should keep it flexible

[t-mat]

First of all, I'm sorry for bad PR. I should have implemented same function and create another issue about fixed filename.

But is such a possibility equally trivial in other languages/frameworks?

No, maybe. Many languages have getopt or something like that. But it is not a part of standard for some languages (eg:C/C++/Java).

Proposal: introduce glue scripts

We want to achieve

• Natural command line arguments for the target languages
• Same and simple command line interface for test automation

So I think it is a good time to introduce small glue scripts which receive same argument but run target scripts/executables with different command-line fashion.

example1: run-goray.sh

#!/bin/sh
MEGAPIXELS=$1
ITERATION=$2
THREADS=$3
OUTPUTFILE=$4
LOGFILE=$5
go run ./gorays/main.go -mp=$MEGAPIXELS -times=$ITERATION -procs=$THREADS -output=$OUTPUTFILE > $LOGFILE

example2: run-cppray.sh

#!/bin/sh
MEGAPIXELS=$1
ITERATION=$2
THREADS=$3
OUTPUT=$4
LOGFILE=$5
./bin/cpprays $MEGAPIXELS $ITERATION $THREADS 1> $OUTPUT 2> $LOGFILE

[kidoman]

Hey, nvm :)

I will merge this in now. I like the idea of wrapper scripts. Lets explore that

[t-mat]

Why check for < 0.0f?

I just implemented standard way for clamping to avoid too early optimization. But it was too naive for such a frequently called function.

Would a min(x, 255) be better?

Yes. Your are right.