7f7553bef2
This one's weird: it doesn't affect the actual generation of ASM in the function, but rather it affects the ASM of sinf and cosf. You see, sinf and cosf are static - they're built right into the EXE. Since the previous code used cosf and sinf, they were embedded into the EXE, and InitTriangleTable would call them directly. However, this isn't what the original EXE does: instead, InitTriangleTable calls an intermediary function, that in turn calls the real cosf and sinf. Turns out this strange code generation is caused by calling cos and sin instead of cosf and sinf, but still using float parameters.
122 lines
1.5 KiB
C++
122 lines
1.5 KiB
C++
#include "Triangle.h"
|
|
|
|
#include <math.h>
|
|
|
|
int gSin[0x100];
|
|
short gTan[0x21];
|
|
|
|
void InitTriangleTable()
|
|
{
|
|
int i;
|
|
float a;
|
|
float b;
|
|
|
|
//Sine
|
|
for (i = 0; i < 0x100; ++i)
|
|
{
|
|
gSin[i] = (int)(sin(i * 6.2831998 / 256.0) * 512.0);
|
|
}
|
|
|
|
//Tangent
|
|
for (i = 0; i < 0x21; ++i)
|
|
{
|
|
a = (float)(i * 6.2831855f / 256.0f);
|
|
b = sin(a) / cos(a);
|
|
gTan[i] = (short)(b * 8192.0f);
|
|
}
|
|
}
|
|
|
|
int GetSin(unsigned char deg)
|
|
{
|
|
return gSin[deg];
|
|
}
|
|
|
|
int GetCos(unsigned char deg)
|
|
{
|
|
deg += 0x40;
|
|
return gSin[deg];
|
|
}
|
|
|
|
unsigned char GetArktan(int x, int y)
|
|
{
|
|
x *= -1;
|
|
y *= -1;
|
|
unsigned char a = 0;
|
|
short k;
|
|
|
|
if (x > 0)
|
|
{
|
|
if (y > 0)
|
|
{
|
|
if (x > y)
|
|
{
|
|
k = (y * 0x2000) / x;
|
|
while (k > gTan[a])
|
|
++a;
|
|
}
|
|
else
|
|
{
|
|
k = (x * 0x2000) / y;
|
|
while (k > gTan[a])
|
|
++a;
|
|
a = 0x40 - a;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (x > -y)
|
|
{
|
|
k = (-y * 0x2000) / x;
|
|
while (k > gTan[a])
|
|
++a;
|
|
a = 0x100 - a;
|
|
}
|
|
else
|
|
{
|
|
k = (x * 0x2000) / -y;
|
|
while (k > gTan[a])
|
|
++a;
|
|
a = 0x100 - 0x40 + a;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (y > 0)
|
|
{
|
|
if (-x > y)
|
|
{
|
|
k = (y * 0x2000) / -x;
|
|
while (k > gTan[a])
|
|
++a;
|
|
a = 0x80 - a;
|
|
}
|
|
else
|
|
{
|
|
k = (-x * 0x2000) / y;
|
|
while (k > gTan[a])
|
|
++a;
|
|
a = 0x40 + a;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (-x > -y)
|
|
{
|
|
k = (-y * 0x2000) / -x;
|
|
while (k > gTan[a])
|
|
++a;
|
|
a = 0x80 + a;
|
|
}
|
|
else
|
|
{
|
|
k = (-x * 0x2000) / -y;
|
|
while (k > gTan[a])
|
|
++a;
|
|
a = 0x100 - 0x40 - a;
|
|
}
|
|
}
|
|
}
|
|
|
|
return a;
|
|
}
|