Regardless of the vbWaitFrame function, I’m with you DogP, I found too many problems using it (mainly because it was not properly implemented since a code like this:
while (VIP_REGS[XPSTTS] & XPBSYR);
when using the optimizing capabilities of the compiler, is and infinite loop) that and the delay is completely random.
but i didn’t found a fix until I properly implemented the clock interrupt, now I have a solution, but it is part of my engine which uses the libgccvb, I use a class called Clock, which implements the following method:
//time delay
void Clock_delay(Clock * const this, u16 miliSeconds){
float time = Clock_getTime(this);
while((Clock_getTime(this)-time)*1000 < miliSeconds);
}
the Clock class has all the necessary information to create a precise delay, so all the Clock's attributes could be expanded as static variables in a c file, but I like to abstract all what I can as a class, and it's is helpul to have more than one clock in a game (more in the vb where you need the automatic pause feature).
I like the open source idea, indeed, my own engine will be released with the whole source code, but it could be helpfull if there is a standard library, one which has the memory mapping, register settings and possible values, etc. And functions implementations can remain open.
About a character printing system, the way I implemented it is using the vbPrint function:
void vbPrint(u8 bgmap, u16 x, u16 y,const char *t_string, u16 bplt);
but since in the engine I'm mannaging the bgmap memory I implemented facade functions:
void printInt(int value,int x,int y);
void printHex(int value,int x,int y);
void printText(char *string,int x,int y);
void printFloat(float value,int x,int y);
and they ask the BGMapManager which is the next free bgmap to use to print text, so this managers keep track of the last bgmap segment used for graphics, and use the next for this kind of printing. I use these functions maily for debugging.
I know that there could be a lot better ways to do it, but I like simple functions which do the hard work for me :-).
I could post the libgccvb I'm using if someone is interested (but be aware that I use the last gccvb which must be compiled).
I almost forget, i have a Textbox class too, which is used to print text but in 3D space, so you can specify the coordinates for the textBox and the engine calculates its parallax, projection, etc. But it is different to the printXXX functions because this kind of text is displayed using a world, and the placement of the text in bgmap memory is optimized.
jorgeche
