Messages

1

Graphics / Re: Faster drawing for multiple shapes

« on: August 25, 2016, 02:50:19 am »

Ok thanks.
Still 1 question: imagine i have to draw the same shape/whatever alot (rly alot) of times.
what option would be faster: Shape or VertexArray?

2

Graphics / Faster drawing for multiple shapes

« on: August 23, 2016, 03:17:04 am »

I have to draw alot of times the same set of shapes, and i would like to know if there is a way to group those together so that i would only need to perform grouping once and that i could draw that on a RenderWindow faster.

3

General / Re: Problem with running a big-array-of-pixels app

« on: July 22, 2016, 11:22:13 pm »

ok now i get it, i was just ignoring the fact texture and sprite would take space in the stack, im really sorry...
i know this question has nothing to do with sfml, but you said i could store the array in the heap, but i should better use vector cause its safe.

what do u mean by 'safe'? i guess you mean std::vector is still stored in the stack, and it is still safer than an array stored in the heap.

1 more question: most of the time, a function that takes an array or an array pointer can also take a vector or a vector pointer?

4

General / Re: Problem with running a big-array-of-pixels app

« on: July 21, 2016, 01:18:10 am »

Thanks alot, the pointer worked.
I'll try to see those compiler stuff, but I was trying not to go really deep into that.

So, basically, it is always best to use a std::vector instead of array, right?
I guess that could be translated to reality as "No-one uses arrays of pixels, just vectors". it is very important to know what are the current standard ways to do stuff. For instance, i first met arrays and then vectors, but as soon as i met vectors i abandoned arrays, as vectors would do the same as arrays and they are more dynamic. so now even for fixed arrays, i replace arrays for vectors.

Another question... As some funny pic states, programmers say "It doesnt work. Why? / It works. Why?"
So why doesnt an array of pixels work?

5

General / Re: Problem with running a big-array-of-pixels app

« on: July 20, 2016, 07:37:08 pm »

I have replaced that statement by std::vector<sf::Uint8> pixels(W*H*4);, but it says:
"error: no matching function for call to 'sf::Texture::update(std::vector<unsigned char>&)".

(actually, sf::Texture::update has no overload for std::vector<>, but only for sf::Uint8, Image and Window)

Also, I've experimented an isolated sf::Uint8 array, and memory is not the problem, since I've tested declarating such an array with 2000*2000*4 elements, and it works fine.

Also, i've tracked the problem to the statement texture.update(pixels);. Still dont understand why.

btw, that statement is not illegal since i've used it in the app i'm developing and it worked fine up to 716*716*4.

6

General / Problem with running a big-array-of-pixels app

« on: July 20, 2016, 06:34:38 pm »

So, this is obviously not my real app, but i managed to isolate it to this piece of code.

#include <SFML/Graphics.hpp>
#include <SFML/Window.hpp>
#include <SFML/System.hpp>
#include <cstdio>

int main()
{
    long int W;
    scanf("%d", &W);
    const long int H = W;

    sf::Texture texture;
    sf::Sprite sprite;

    if(!texture.create(W, H)) throw "ERR";

    sf::Uint8 pixels[W*H*4];
    texture.update(pixels);
    sprite.setTexture(texture);

    return 0;
}

In the actual program, I'm manipulating an array of pixels pixel-by-pixel.
I've tested for W=716 and lower values, and it presented the standard "Status 0" stuff at the end.
But for W=717 and larger values, a box pops up, where you can read:

"ProblemProject.exe stopped working
Windows is searching for a solution to the problem..."

and then another one saying:

"ProblemProject.exe stopped working
Windows is collecting information about the problem. This process might take several minutes..."

and finally one saying:

"ProblemProject.exe stopped working
A problem led to the program to stop working correctly. Windows will close the program and warn you if there is a possible solution."

I click a "Close program" button, and the Console presents the message:

"Process returned 255 (0xFF)   execution time : 9.685 s
Press any key to continue."

I've tested the code for a full-window (red-coloured xd) rectangle shape and it worked fine for every value of W.

I'm using static (and static debug as well) versions of all the SFML 2.3.2 libraries (both with -s and -s-d i get the same thing), and using
CodeBlocks Release 13.12 rev 9501 (2013/12/25 19:25:45) gcc 4.7.1 Windows/unicode - 32 bit

I'm working on Windows10, and my GPU is NVIDIA GEFORCE GTX 950M.

Please help me, I'm almost certain it must be a begginer's issue, but I still couldn't find any related post.