//declarations
float x,y;
int i;
char* text[10];
int InitGL(GLvoid)
{
//...init stuff
x = 30; y = 469; i = 0;
text[0] = "Scrolling text";
text[1] = "bla bla";
text[2] = "bla bla again"
}
int DrawGLScene(GLvoid)
{
//draw stuff
glScissor(2, 2, 780, 580);
glEnable(GL_SCISSOR_TEST); glColor4f(1.0,1.0,1.0,1.0);
glPrint(((int) x),((int)y),0,((const char* )text));
glDisable(GL_SCISSOR_TEST); y-=0.1;
i++;
glFlush();
}
If i use glPrint(((int) x),((int)y),0,((const char* )text[0]));
it works showing one single line scrolling up the screen, but if i try to make a loop (like in the example above) so that all the 3 lines scroll together one after the other the program crashes...
Any ideas on how to make it work ?
Edited by - ezekio on November 18, 2001 1:38:48 PM
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how to write a scroller
November 18, 2001 12:36 PM
Hy all you opengl programmers...
I have a problem for sometime now : i want to write a scroller but don't quite know how, this is what a managed to do so far :
linux resistance is full
126
November 18, 2001 01:32 PM
hmm what is up with this line:
glPrint(((int) x),((int)y),0,((const char* )text));
?
first of all, if I understand what you're doing right, shouldn't it be text?
also I don't understand how you're doing the integer casting. The way I do it is int(x) not (int) x
unless there is something different about how your compiler does casting, but then it wouldn't be ansi C I suppose.
hmmm I see the i in brackets won't show up
i meant:
oh and if you want to display source code the code for it is
[ source ]
.... your code here...
[ / source ]
without the spaces
Edited by - element2001 on November 18, 2001 2:39:53 PM
glPrint(((int) x),((int)y),0,((const char* )text));
?
first of all, if I understand what you're doing right, shouldn't it be text?
also I don't understand how you're doing the integer casting. The way I do it is int(x) not (int) x
unless there is something different about how your compiler does casting, but then it wouldn't be ansi C I suppose.
hmmm I see the i in brackets won't show up
i meant:
|
oh and if you want to display source code the code for it is
[ source ]
.... your code here...
[ / source ]
without the spaces
Edited by - element2001 on November 18, 2001 2:39:53 PM
122
November 18, 2001 01:45 PM
(int) x is the good old fashioned c-style cast. int(x) is the "functional cast" notation that was brought in for the early drafts of the c++ standard (which does the same thing as the old cast).
Officially, both types have been replaced by the new c++ casts:
You`ll still see old c hacks like myself using the classic cast notation every now and then (even though its been depreciated). They are more concise, but easy to misuse.
EDITL Forgot the source tags...
Edited by - Krunk on November 18, 2001 2:46:50 PM
Officially, both types have been replaced by the new c++ casts:
|
You`ll still see old c hacks like myself using the classic cast notation every now and then (even though its been depreciated). They are more concise, but easy to misuse.
EDITL Forgot the source tags...
Edited by - Krunk on November 18, 2001 2:46:50 PM
122
November 18, 2001 01:55 PM
Wow, this doesn''t make sense to me at all. How did you get this to compile?
1. How exactly are you assigning text into the CHAR POINTER ARRAY. It''s a char pointer, not a buffer. You need a buffer...
-nt20
"nikolatesla20"
1. How exactly are you assigning text into the CHAR POINTER ARRAY. It''s a char pointer, not a buffer. You need a buffer...
-nt20
"nikolatesla20"
"nikolatesla20"
126
November 18, 2001 04:01 PM
Yes, that and also when you increment i++ wouldn''t it go above 10 which would put it past the last element in the array? assuming you had the assignments of text right which they aren''t either as NikolaTesla pointed out.
November 19, 2001 06:00 AM
well first of all the code works 
second this is how i declared the function glPrint
I was using code & /code from another forum
Anyway besides my bad english (sorry) i still don't have a good method to scroll some texts . Any ideeas ?
To be more specific i'm trying to do something like the end scroller from the fr8-08 demo ...
Edited by - ezekio on November 19, 2001 7:01:48 AM
second this is how i declared the function glPrint
|
I was using code & /code from another forum
Anyway besides my bad english (sorry) i still don't have a good method to scroll some texts . Any ideeas ?
To be more specific i'm trying to do something like the end scroller from the fr8-08 demo ...
Edited by - ezekio on November 19, 2001 7:01:48 AM
linux resistance is full
1,658
November 19, 2001 06:20 AM
nikolatesla20:
A string is an array of char.
Arrays and pointers are interchangeable (except for memory management issues )
A static chain (one you have in your code) can be assigned to a char* without any problems... so long as you don't try to modify the string itself.
edit:
And a buffer is a space in memory... in this case, represented by a pointer to char, that is, a char array.
Edited by - Fruny on November 19, 2001 7:22:14 AM
A string is an array of char.
Arrays and pointers are interchangeable (except for memory management issues
)A static chain (one you have in your code) can be assigned to a char* without any problems... so long as you don't try to modify the string itself.
edit:
And a buffer is a space in memory... in this case, represented by a pointer to char, that is, a char array.
Edited by - Fruny on November 19, 2001 7:22:14 AM
"Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it." — Brian W. Kernighan
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