Inconsistent speed when changing window size | Together C & C++ | Page 1

hexed smeltBOT Jul 6, 2024, 4:13 AM

#

When your question is answered use !solved to mark the question as resolved.

Remember to ask specific questions, provide necessary details, and reduce your question to its simplest form. For tips on how to ask a good question use !howto ask.

dense orchid Jul 6, 2024, 4:15 AM

#

Hello, no one will download a zip

#

Please paste your code

hasty saffron Jul 6, 2024, 4:15 AM

#

dense orchid Hello, no one will download a zip

this

bleak trench Jul 6, 2024, 4:15 AM

#

!howto ask

hexed smeltBOT Jul 6, 2024, 4:15 AM

#

bleak trench !howto ask

How to Ask a Programming Question

Anyone can ask a question in our programming channels. Following the guide Writing The Perfect Question is recommended.

What to Post

State your problem clearly and provide all necessary details:

the relevant portion of your code, or all of it
the expected output
the actual output (or the full error)
:trophy: Gold Standard: Minimal Reproducible Example

Where to Post

Provide the relevant code in the message, and format it nicely with a code block*. If it's too much for one message, you can upload it:

Compiler Explorer for most C and C++ snippets
OnlineGDB for interaction, debugging
:no_entry: Do not post screenshots, let alone photos of your screen!

swift coyote Jul 6, 2024, 4:16 AM

#

dense orchid Please paste your code

There are multiple files

#

So do I just paste all?

dense orchid Jul 6, 2024, 4:16 AM

#

!howto ask

hexed smeltBOT Jul 6, 2024, 4:16 AM

#

dense orchid !howto ask

How to Ask a Programming Question

Anyone can ask a question in our programming channels. Following the guide Writing The Perfect Question is recommended.

What to Post

State your problem clearly and provide all necessary details:

the relevant portion of your code, or all of it
the expected output
the actual output (or the full error)
:trophy: Gold Standard: Minimal Reproducible Example

Where to Post

Provide the relevant code in the message, and format it nicely with a code block*. If it's too much for one message, you can upload it:

Compiler Explorer for most C and C++ snippets
OnlineGDB for interaction, debugging
:no_entry: Do not post screenshots, let alone photos of your screen!

dense orchid Jul 6, 2024, 4:16 AM

#

read the last 3 lines of that^

bleak trench Jul 6, 2024, 4:17 AM

#

swift coyote So do I just paste all?

The more code you send, the less likely anyone will help, unfortunatley

#

No one wants to read hundreds of lines

#

It's best if you can send just the relevant parts

swift coyote Jul 6, 2024, 4:18 AM

#

float delta_time = 0.016666f;
LARGE_INTEGER frame_begin_time;
QueryPerformanceCounter(&frame_begin_time);

float performance_frequency;
{
    LARGE_INTEGER perf;
    QueryPerformanceFrequency(&perf);
    performance_frequency = (float)perf.QuadPart;
}

simulate_game(&input, delta_time);
LARGE_INTEGER frame_end_time;
QueryPerformanceCounter(&frame_end_time);
delta_time = (float)(frame_end_time.QuadPart - frame_begin_time.QuadPart) / performance_frequency;
frame_begin_time = frame_end_time;

simulate_game(Input* input, float dt) {
clear_screen(0xff5500);

float speed = 5.f; // Units per second
if (is_down(BUTTON_UP)) player_pos_y += speed * dt;
if (is_down(BUTTON_DOWN)) player_pos_y -= speed * dt;
if (is_down(BUTTON_LEFT)) player_pos_x -= speed * dt;
if (is_down(BUTTON_RIGHT)) player_pos_x += speed * dt;
draw_rect(player_pos_x, player_pos_y, 0.5, 0.5, 0x00ff22);

#

I guess these are all of the important parts

#

Basically it calculates second per frame

#

From what the video told me

#

And then it just take delta_time and multiply with speed

bleak trench Jul 6, 2024, 4:20 AM

#

!code

hexed smeltBOT Jul 6, 2024, 4:20 AM

#

How to Format Code on Discord

Markup

```cpp
int main() {}
```

Result

int main() {}

swift coyote Jul 6, 2024, 4:22 AM

#

internal void
simulate_game(Input* input, float dt) {
    clear_screen(0xff5500);

    float speed = 5.f; // Units per second
    if (is_down(BUTTON_UP)) player_pos_y += speed * dt;
    if (is_down(BUTTON_DOWN)) player_pos_y -= speed * dt;
    if (is_down(BUTTON_LEFT)) player_pos_x -= speed * dt;
    if (is_down(BUTTON_RIGHT)) player_pos_x += speed * dt;
    draw_rect(player_pos_x, player_pos_y, 0.5, 0.5, 0x00ff22);

}
int main(){
  float delta_time = 0.016666f;
    LARGE_INTEGER frame_begin_time;
    QueryPerformanceCounter(&frame_begin_time);

    float performance_frequency;
    {
        LARGE_INTEGER perf;
        QueryPerformanceFrequency(&perf);
        performance_frequency = (float)perf.QuadPart;
    }
   simulate_game(&input, delta_time);
  LARGE_INTEGER frame_end_time;
    QueryPerformanceCounter(&frame_end_time);
    delta_time = (float)(frame_end_time.QuadPart - frame_begin_time.QuadPart) / performance_frequency;
    frame_begin_time = frame_end_time;
}

dense orchid Jul 6, 2024, 4:24 AM

#

And you need to calculate length of each frame?

#

To fix your issue?

swift coyote Jul 6, 2024, 4:26 AM

#

From the video I watched. Yes that's what they did

#

And then they used that time length and multiply with speed

dense orchid Jul 6, 2024, 4:26 AM

#

Speed of what

swift coyote Jul 6, 2024, 4:27 AM

#

Movement speed

#

Of the object that the user controls

#

They did that so the movement speed doesn't change when the window changes in size

dense orchid Jul 6, 2024, 4:28 AM

#

so the speed of the square/rectangle your drawing changes when you resize the application window

swift coyote Jul 6, 2024, 4:29 AM

#

Yes that's the problem

#

The smaller the application window

dense orchid Jul 6, 2024, 4:29 AM

#

swift coyote And then they used that time length and multiply with speed

So why cant you do this

#

i see your code calculating the length

swift coyote Jul 6, 2024, 4:30 AM

#

It does that but I don't know why it doesn't apply

#

So it does calculate the length

#

And I multiply the length with movement speed

#

But the movement speed changes

#

Despite that

dense orchid Jul 6, 2024, 4:32 AM

#

swift coyote And I multiply the length with movement speed

So you multiply speed with length to get this new speed value or whatever

#

What are you doing with this value

#

Where is that handled

#

is length * initial rect speed = new rect speed

#

or what does this value represent

swift coyote Jul 6, 2024, 4:34 AM

#

dense orchid is length * initial rect speed = new rect speed

Yes that is what I want to do

#

You can see that in simulate_game function

dense orchid Jul 6, 2024, 4:34 AM

#

swift coyote You can see that in simulate_game function

No

#

I only see you subtract initial frame time from final frame time

#

And divide it by “performance frequency”

#

i dont see you setting it to be the new speed of the rectangle

swift coyote Jul 6, 2024, 4:39 AM

#

I guess it's time * speed = distance
Speed is already determined (5.f)
So what I want is for the time to change so that distance between first pos and next pos stays the same throughout despite the size of the window
However, time doesn't change or something not working which results in smaller window => distance longer I guess

#

Can I send video for you to see the problem?

#

I think it will be a bit easier if you can see the problem

dense orchid Jul 6, 2024, 4:41 AM

#

swift coyote Can I send video for you to see the problem?

Sure

#

send relevant timestamps too

swift coyote Jul 6, 2024, 4:46 AM

#

At 50 second is where you can see my problem

#

The first part is the expected output

#

I'm currently learning this course on youtube

#

Hope this helps a bit

#

If you need more information, I will try to provide all everything

#

I will comeback after half an hour

#

Thankyou for taking your time looking into this

hexed smeltBOT Jul 6, 2024, 4:56 AM

#

@swift coyote Has your question been resolved? If so, type !solved :)

hexed smeltBOT Jul 6, 2024, 7:49 AM

#

@swift coyote

Please Do Not Delete Posts!

Please don't delete forum posts. They can be helpful to refer to later and other members can learn from them. In the future you can use !solved to close a post and mark a post as solved.

swift coyote Jul 6, 2024, 8:27 AM

#

!solved

#Inconsistent speed when changing window size