So, in a program I'm making, I have an idea, that I can print the character background first, then print another layer on top of the background. Can I do that? But I need to be able to place a single character at a certain position, what function does that?
View 5 RepliesI have a linear buffer coordinate, i am to print onto a screen coordinate.
Say maxy = 20, maxx = 10, bufferx = 20, y, x,
Buffer coordinates to screen coordinates:
Algorithm: So for each maxx'th of bufferx, y will +1 and x will reset.
Mathematical: y = int bufferx / maxx,
const double averageIncr = int (maxx+1/maxx) - double (maxx+1/maxx);
So the amount of averageIncr in (int bufferx / maxx - float bufferx / maxx)
is the screen x coordinate. Then
(int bufferx / maxx - float bufferx / maxx) / averageIncr = x
Screen coordinates to buffer coordinates:
bufferx, y = 21, x = 10, maxy = 20, maxx = 10,
y * x would be the case if bufferx <= max screen coordinate.
There is no max bufferx.
How to find the transition from screen coordinates to buffer coordinates? Also, if the algorithm within a for loop, or that the mathematical way would be slower or not? I rarely touch floating point stuff.
I'm writing a program that stores records into a file and then these records can be printed out. A last name, first name, and score is stored to be exactly 36 characters long (using leading spaces to pad) making it easier to retrieve specific records. For example, three records stored in the file would like like this: (the underscores are simply to illustrate the distance, they are not in the file itself)
_______lastname_______firstname__90__________lname __________fname_100___________last___________first __60
When printed out, the names are formatted as follows:
lastname, firstname: 90
lname, fname: 100
last, first: 60
However, when I print them out this is what I get:
lastname, firstname: 90
lname, fname: 100$
last, first: 60H
For some reason, for any record after the first, an extra character is added to the end. These characters are not in the file, so I was thinking that the array for some reason wasn't being filled completely, (the array is initialized to size 36 and 36 characters are read from the file using fread) so it was printing out a random character assigned to the 36th array position. Except the character never changes, (always a $ for record 2, H for record 3, l for record 4 if i remember) and I've tried reducing the array size or the number of character read and it's the string that gets altered, the random character always remains. I figure the problem must be in the print_records function (appending seems to work no problem). Anyway here is my print records and appending records code.
Code: /*
- Prints a single record stored in the file pointed to by ifp.
*/
void print_record(FILE *ifp, int record) {
[Code]......
I have a character at a co-ordinate, say (3,4) for example, and I need to get him to (10,15). I would like him to move one block every tick or half a second, so that you can see him moving towards his destination. How to achieve this?
View 3 Replies View RelatedHow can i convert pixel to [-1..1]coordinate in opengl? Which function? I want to write a program that is work with
glutmousefunc(),
When I click on the screen a ball is appear on it where clicked. but mouse work with pixel and circle work with coordinate between -1 and 1 ....
After searching on stackoverflow I got this
POINT p;
for (int i = 0;; ++i) {
HWND hwnd = GetConsoleWindow();
system("cls");
if (ScreenToClient(hwnd, &p)) {
//p.x and p.y are now relative to hwnd's client area
} cout << p.x << " " << p.y;
Sleep(200);
}
I'm looking for a function that gives current mouse position(x and y) in that particular console window. I've tried above code but it is not working.
I have 2 points in a cartesian coordinate system, where the first point is always (0,0). Given the second point and a heading in degrees, how would I write an algorithm to determine if the 2nd point is traveling in the general direction of (0,0) ?
For example:
Point a (0,0)
Point b (10,0)
Point b heading = 270 degrees
This would be true this 270 degrees points right and point b is 10 units right of point a. I would probably also want this is be fuzzy somewhat, in that anything from say + or - 30 degrees would also be true, or something like this.
Cam is a pointer to a structure and viewpoint is a vector located within the struct. I am trying to read in from a file the coordinates for the vector. I have also tried &cam->view_point->x as well as &cam.view_point.x and it tells me that I am requesting something not in a struct
Code: count= fscanf(in,"%d %d %d", &cam->view_point.x, &cam->view_point.y,&cam->view_point.z);
How to read pixels from an x,y coordinate using the VGA register values?
byte readVRAMdirect(VGA_Type *VGA, uint_32 start, uint_32 offset) //Used in 256 color mode!
{
if (!VGA->VRAM_size) return 0; //No size!
return VGA->VRAM[SAFEMOD((start*4)+offset,VGA->VRAM_size)]; //The full protected offset!
[code]....
getVRAMScanlineStart(VGA,y) gives the offset register multiplied by 2 (shl 1), multiplied with the current memory address size (byte, word or dword) multiplied by the scanline. 256-color mode is already working. GETBIT gives a bit #(0-7) of a specified byte.
writeVRAMplane & readVRAMplane are used by the CPU to write data to VRAM (address 0xA000:xxxx-0xBFFF:xxxx), determined by the memory read and write modes(working) and the odd/even, planar or chain4 enable mode (working).how to get the 16 color and interleaved shift mode working?
ZIP with screen captures: URL....
I am drawing in a simple (square) MFC window. I realize that (0,0) starts in the upper left hand corner. I wanted to see how MFC handled drawing of angles, so I use this code:
Code:
double CompassDegreesToRadians(double compassDegrees) {
return((PI / 2.0f) - (compassDegrees * PI / 180.0f));
}
// Make pen
CPen penRed;
penRed.CreatePen(PS_SOLID | PS_COSMETIC, 1, RGB(255, 0, 0));
// Test Angles
[Code] .....
Using this code, and changing the value of angle1 to these values (0, 90, 180, 270) I think MFC uses the coordinate system:
Code:
180 -y
|
|
-x 270---------------- 90 +x
|
|
0 +y
This seems like a strange coordinate system to use. Am I doing something wrong? If this is correct, how can I convert my calculations to this coordinate system? (compass degrees):
Code:
0 +y
|
|
-x 270---------------- 90 +x
|
|
180 -y
I am very much new to C programming. However, I have an assignment regarding linked list.
Problem Statement is: Using linked list store the coordinates of four cartesian points and then find the coordinates having longest distance from its origin.
I keep getting this warning message and I do not know how to fix it. Is it because I'm using char to instead of strings to replace all 't' with 'lp'?
#include<iostream>
#include<string>
#include <stdio.h>
using namespace std;
char * scanf(char * a) {
[code]....
Double values are stored in text file. 23.5 36.8 34.2 ... My teacher told me to read them character by character and then make words, like i have to read "2" "3" "." "5" and now have to make it or treat it as word and then using atoi(). I have to convert it into double. but i dont know how to do this....
View 5 Replies View RelatedI have to optimize a code for below scenario. I am reading stdin (a file redirected to stdin) character by character. How many chars are going to come is not known. After every few chars there is a seaparator. e.g $ as below
rhhrkkj$hghjhdf$ddfkrjt
While reading, if the separator arrives I'm processing the string stored before that separator and then continue reading stdin in same fashion, till EOF. I am using getc(stdin) to read chars.
Using gprof I can see most of the program time is spent inside main() , for this reading logic. Rest of the program is just some insert and search operations. I am getting time of 0.01 secs at the moment, want to reduce further.
How do I write an a program that will read an input file character by character?
View 1 Replies View RelatedIn my program, I'm supposed to read a text file (the name of which is given to me as a command line paramater, as long with an integer), and display the text in a specific format (each line can only be as long as the integer). However, I'm having trouble even reading the text file. I don't know the syntax. I'm only allowed to edit the function that does the formatting, and the code in that is
void typeset (int maxWidth, istream& documentIn)
I don't know how to 'read' the file, as most examples online are ifstream, or openFile or something like that. What I want to do is just read the first character of the file, and continuously keep reading characters until the end of the file.
So I'm trying to create a function that replaces any instance of a character in a string with another. So first I tried the replace() string member function:
In my implementation file
void NewString::ReplaceChar(const char& target,const char& entry)
{
this->replace(this->begin(),this->end(), target, entry);
};
Main program
#include "NewString.h"
using namespace ...;
int main()
[Code].....
Instead of replacing the the l's with y's it outputted a long string of y's. Also, NewString is derived from the string class (it's for the assignment). the header and whole implementation file, already tested.
I've also tried, instead, to use a for loop in ReplaceChar() but I need to overload the == operator and I don't know how I should exactly:
bool NewString::operator ==(const char& target)const {
if(*this == target)
return true;
[Code]....
I want the == operator to test if the value in the char array is equal to target but I'm not sure how to pass in the position. I'm guessing the this pointer in ReplaceChar() is not the same as the one dereferenced in ==() because target is never replaced by entry in the string.
Can we do this :
Code:
char strings[][100]={"ABC","EFG","IJK","LKM"};
char temp[100];
temp=strings[1];
What the heck is wrong with my logic? I just print a rectangle!!! I have played with thing for ever it seems. I thought the rotating part would be hard but now I find myself stuck.
Code:
#include <istream>
#include "triangle.h"
using namespace std;
void triangle::create_triangle() {
[Code] ....
I need c source that give the url txt file and print the txt file
(get the http://site.com/text.txt) and print the (text.txt) file Content.
I have an array, ary[size+1] and the original values entered and then another value, x, entered. I found the index of x that makes the array nondecreasing order
Code:
void InsertX (int ary[], int size, int x)
{
int i=0;
int j;
int index;
while(ary[i]<x)
[Code]...
But i can't figure out how to print the new array with x in it, using its index
how to print a box using 2d arrrays. i have to create a tetris game which a im stuck at this stage... so far i have tired i can only come out with this..my coding done so far is as follows:
Code:
#include <stdio.h>
#define ROW 15
#define COLUMN 15
void disp_box (char b[ROW][COLUMN])
}
[code]....
I expected this program to print out:
Code: Enter your desired monthly salary: $2000___
Gee! $2000.00 a month is $24000.00 a year. Instead, it printed out:
Code: Enter your desired monthly salary: $2000___
Gee! $2000.00 a month is $24000.00 a year. I don't understand how it got the extra nextline in the middle.
Here is the code:
Code:
#include <stdio.h>
int main(void) {
float salary;
printf("aEnter your desired monthly salary:");
[Code].....
#include <iostream>
#include <string>
using namespace std;
struct studentType {
string name;
double gpa;
[Code] .....
#include <iostream>
using std::cout;
using std::cin;
using std::endl;
using std::ios;
#include "Course.h"
#include <list>
[Code] ....
The program works well, except for the fact when it prints out the list (starting at the for-loop on line 65) each line is the same as the last, like it overwrites itself every time it traverses the while(true) loop.
I have previous threads asking how to make a list of words that were matched up be printed out into a .css or .txt
Is there anyway to make the words being printed out in CMD after debugging/compiling a script printed out in a .txt/.cpp file instead? CMD only has 300 lines. I need the outcome to be printed out elsewhere so more lines can be posted rather than 300.