Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Levi]

You probably need to re-render with each frame.

Something like:  TCODConsole::root->console_flush()   in your while loop.

(although I'm not sure of the exact syntax)

[Simmura McCrea]

Same thing, just a blank frozen window.

[Sirus]

I don't know what a 201 course is, but it's not quite an introductory course. The class has a pre-requisite called Computer Logic, which I assume would cover these things. Problem is, I took that class several years ago, and it was basically making endless flow charts and a little bit of pseudocode. No real code involved in any language. Talking to the other students, it seems like the curriculum changed a great deal while I was gone, and actually does some Assembly or UNIX or something now. It's still supposed to be a basics class, since we started with the classic Hello World and began working our way up.

[Simmura McCrea]

You probably need to re-render with each frame.

Something like:  TCODConsole::root->console_flush()   in your while loop.

(although I'm not sure of the exact syntax)

That's got it. Cheers.

[MaximumZero]

Why does OOP feel so different than Procedural programming? I'm freaking lost. I don't even know what I'm supposed to be doing.

[Levi]

Why does OOP feel so different than Procedural programming? I'm freaking lost. I don't even know what I'm supposed to be doing.

Just pretend you are doing procedural programming then, but:

- If you have data, put it in an class.
- If you have a function that manipulates that data, put that function in the same class.

Although I suppose depending on what you are working on, that might not always work. 

[Sirus]

Ok, I've been beating my head against this problem for the past two hours, and this assignment is due by midnight, so if I could kindly have a little help? I think the problem is that it's not calling the calculate function properly, as the program will run, and it'll do the printf() statements just fine, but I just get zeroes and 8-digit numbers.

Spoiler (click to show/hide)

Code: [Select]

#include <stdio.h>

#define TAX_RATE 8.50

//Function Declarations
void getData(int*, float*, float*);
void calculate(float*, int*, float*, float*, float*, float*, float*, float*);
void outputData();

int main (void)
{
// Local Declarations
int    quantity;

float  discountRate;
float  discountAm;
float  unitPrice;
float  subTotal;
float  subTaxable;
float  taxAm;
float  total;

// Statements
getData(&quantity, &unitPrice, &discountRate);
calculate(&subTotal, &quantity, &unitPrice, &discountAm, &discountRate, &subTaxable, &taxAm, &total);
outputData(&quantity, &unitPrice, &subTotal, &discountAm, &subTaxable, &taxAm, &total);

return 0;
} // main

void getData(int *quantity, float *unitPrice, float *discountRate)
{
//Statements
printf("\nEnter number of items sold:         ");
scanf("%d", &*quantity);

printf("Enter the unit price:               ");
scanf("%f", &*unitPrice);

printf("Enter the discount rate (per cent): ");
scanf("%f", &*discountRate);

return;
}

void calculate(float subTotal, int quantity, float unitPrice, float discountAm, float discountRate, float subTaxable, float taxAm, float total)
{
//Calculations
subTotal    = quantity * unitPrice;
discountAm  = subTotal * discountRate / 100.0;
subTaxable  = subTotal - discountAm;
taxAm = subTaxable * TAX_RATE/ 100.00;
total = subTaxable + taxAm;

return;
}

void outputData(int quantity, float unitPrice, float subTotal, float discountAm, float subTaxable, float taxAm, float total)
{
//Statements
printf("\nQuantity sold:       %6d\n", quantity);
printf("Unit Price of items: %9.2f\n", unitPrice);
printf("                     ------------\n");

printf("Subtotal :           %9.2f\n", subTotal);
printf("Discount:           -%9.2f\n", discountAm);
printf("Discounted total:    %9.2f\n", subTaxable);
printf("Sales tax:          +%9.2f\n", taxAm);
printf("Total sale:          %9.2f\n", total);
}

The only error I can see on-screen (and again, the program will actually run with it), is a red line under the outputData statement in the main function. Mousing over it gives the message "no instance of overloaded function "outputData" matches the argument list".

[RulerOfNothing]

Well, have you tried removing the &* from the getData function? If that doesn't work, you should at least have the program echo the inputted values to check if they got into the program correctly.

[Sirus]

Same result as before. Damn.

[Xegeth]

You have the wrong function declarations. outputData needs arguments on line 8, and calculate uses pointers in the declaration but not the definition. I'd guess the program runs because it compiled in the past and you're using the old version of the program.

[Max White]

Yea, what Xegeth said. For example, first few lines of code should be...

Code: [Select]

#include <stdio.h>

#define TAX_RATE 8.50

//Function Declarations
void getData(int*, float*, float*);
void calculate(float*, int*, float*, float*, float*, float*, float*, float*);
void outputData(int quantity, float unitPrice, float subTotal, float discountAm, float subTaxable, float taxAm, float total)

[kaijyuu]

Wonder if anyone here has any experience with this....


I'm tired of hardcoding behavior of sprites/etc in my game. Compile times get incredibly long when doing it in raw c++, plus making tools for myself would make things much less tedious and repetitive. I need to stop putting attributes in the c++ files themselves, and make me a tool where I can modify and import them into the game, like a real engine.

So I need to implement a scripting language for behavior. Any suggestions? I'm looking into Lua right now and it looks pretty nifty. However I have zero experience with it (or most scripting languages, really) so before I take the dive I'd like some second opinions. Some friends of mine are suggesting Python, as well.

It just needs to be able to interact with c++ and be easily written within a Qt application (which I'll be making my tools with --  has decent text editor functionality IIRC so that shouldn't be an issue). Speed is also a factor, as I'll be using it for everything's behavior, including stuff like particle effects. I'd love to write my own, but I don't want to spend 3 years making this, when I can have a much more versatile language implemented in half the time. Plus I plan to release this game engine someday, and a well known language will make it easier for people to pick up.

[fergus]

First, there's some problems with function definitions:

Code: [Select]

void calculate(float*, int*, float*, float*, float*, float*, float*, float*);
void calculate(float subTotal, int quantity, float unitPrice, float discountAm, float discountRate, float subTaxable, float taxAm, float total)
This is probably your problem, I'm pretty sure you want to pass by value, not by reference, so remove the *'s from the first line.

Code: [Select]

void outputData();
void outputData(int quantity, float unitPrice, float subTotal, float discountAm, float subTaxable, float taxAm, float total)
I'm surprised this even compiles without an error, but you need to change the first line to match the second.

As for actually calling them:

Code: [Select]

calculate(&subTotal, &quantity, &unitPrice, &discountAm, &discountRate, &subTaxable, &taxAm, &total);
outputData(&quantity, &unitPrice, &subTotal, &discountAm, &subTaxable, &taxAm, &total);
Both of these are wrong: outputData doesn't need pointers and calculate does need them, but doesn't dereference them properly, it does direct arithmetic on the values passed, not on the values pointed to, which explains the large numbers. To do this correctly, you should dereference the pointers in calculate when you use them.

Third, you should remove the &* from getData, printf doesn't generally use pointers and you should pass the values instead.

[Sirus]

Ok, I made those changes (though I can't say I remember seeing that in any of my previous assignments, sample programs, or notes, but w/e), and got rid of the ampersands in the outputData statement (they were showing up as an error). This got the program to run, but the results for each of the calculations are -107374176.00. I'm assuming that that's not correct, so back to the drawing board I go.

Fergus, a quick look in my textbook's index shows that "dereference" doesn't show up for another 400 pages. In simple English, please?

[Max White]

*Facepalm*
In programming, when you have an error, and you have several theories on how to solve it, it is best to keep your testing atomic.
That is to say, implement one solution, test it, and if it works you are set! Otherwise, undo the changes and try the next idea... Why would you remove the ampersands and extend the signature of the forward deceleration without testing in between?