* (bug #3639) BoxOnPlaneSide rewrite (Diego de Estrada/Patrick Bagget/Daniel

  Gibson)


git-svn-id: svn://svn.icculus.org/quake3/trunk@1635 edf5b092-35ff-0310-97b2-ce42778d08ea

1 files changed, 15 insertions, 315 deletions

diff --git a/code/qcommon/q_math.c b/code/qcommon/q_math.c
index 80c9f8e..d2e0187 100644
--- a/code/qcommon/q_math.c
+++ b/code/qcommon/q_math.c
@@ -647,50 +647,14 @@ void SetPlaneSignbits (cplane_t *out) {
 BoxOnPlaneSide
 
 Returns 1, 2, or 1 + 2
-
-// this is the slow, general version
-int BoxOnPlaneSide2 (vec3_t emins, vec3_t emaxs, struct cplane_s *p)
-{
-	int		i;
-	float	dist1, dist2;
-	int		sides;
-	vec3_t	corners[2];
-
-	for (i=0 ; i<3 ; i++)
-	{
-		if (p->normal[i] < 0)
-		{
-			corners[0][i] = emins[i];
-			corners[1][i] = emaxs[i];
-		}
-		else
-		{
-			corners[1][i] = emins[i];
-			corners[0][i] = emaxs[i];
-		}
-	}
-	dist1 = DotProduct (p->normal, corners[0]) - p->dist;
-	dist2 = DotProduct (p->normal, corners[1]) - p->dist;
-	sides = 0;
-	if (dist1 >= 0)
-		sides = 1;
-	if (dist2 < 0)
-		sides |= 2;
-
-	return sides;
-}
-
 ==================
 */
-
-#if !id386
-
-int BoxOnPlaneSide (vec3_t emins, vec3_t emaxs, struct cplane_s *p)
+int BoxOnPlaneSide(vec3_t emins, vec3_t emaxs, struct cplane_s *p)
 {
-	float	dist1, dist2;
-	int		sides;
+	float	dist[2];
+	int		sides, b, i;
 
-// fast axial cases
+	// fast axial cases
 	if (p->type < 3)
 	{
 		if (p->dist <= emins[p->type])
@@ -700,291 +664,27 @@ int BoxOnPlaneSide (vec3_t emins, vec3_t emaxs, struct cplane_s *p)
 		return 3;
 	}
 
-// general case
-	switch (p->signbits)
+	// general case
+	dist[0] = dist[1] = 0;
+	if (p->signbits < 8) // >= 8: default case is original code (dist[0]=dist[1]=0)
 	{
-	case 0:
-		dist1 = p->normal[0]*emaxs[0] + p->normal[1]*emaxs[1] + p->normal[2]*emaxs[2];
-		dist2 = p->normal[0]*emins[0] + p->normal[1]*emins[1] + p->normal[2]*emins[2];
-		break;
-	case 1:
-		dist1 = p->normal[0]*emins[0] + p->normal[1]*emaxs[1] + p->normal[2]*emaxs[2];
-		dist2 = p->normal[0]*emaxs[0] + p->normal[1]*emins[1] + p->normal[2]*emins[2];
-		break;
-	case 2:
-		dist1 = p->normal[0]*emaxs[0] + p->normal[1]*emins[1] + p->normal[2]*emaxs[2];
-		dist2 = p->normal[0]*emins[0] + p->normal[1]*emaxs[1] + p->normal[2]*emins[2];
-		break;
-	case 3:
-		dist1 = p->normal[0]*emins[0] + p->normal[1]*emins[1] + p->normal[2]*emaxs[2];
-		dist2 = p->normal[0]*emaxs[0] + p->normal[1]*emaxs[1] + p->normal[2]*emins[2];
-		break;
-	case 4:
-		dist1 = p->normal[0]*emaxs[0] + p->normal[1]*emaxs[1] + p->normal[2]*emins[2];
-		dist2 = p->normal[0]*emins[0] + p->normal[1]*emins[1] + p->normal[2]*emaxs[2];
-		break;
-	case 5:
-		dist1 = p->normal[0]*emins[0] + p->normal[1]*emaxs[1] + p->normal[2]*emins[2];
-		dist2 = p->normal[0]*emaxs[0] + p->normal[1]*emins[1] + p->normal[2]*emaxs[2];
-		break;
-	case 6:
-		dist1 = p->normal[0]*emaxs[0] + p->normal[1]*emins[1] + p->normal[2]*emins[2];
-		dist2 = p->normal[0]*emins[0] + p->normal[1]*emaxs[1] + p->normal[2]*emaxs[2];
-		break;
-	case 7:
-		dist1 = p->normal[0]*emins[0] + p->normal[1]*emins[1] + p->normal[2]*emins[2];
-		dist2 = p->normal[0]*emaxs[0] + p->normal[1]*emaxs[1] + p->normal[2]*emaxs[2];
-		break;
-	default:
-		dist1 = dist2 = 0;		// shut up compiler
-		break;
+		for (i=0 ; i<3 ; i++)
+		{
+			b = (p->signbits >> i) & 1;
+			dist[ b] += p->normal[i]*emaxs[i];
+			dist[!b] += p->normal[i]*emins[i];
+		}
 	}
 
 	sides = 0;
-	if (dist1 >= p->dist)
+	if (dist[0] >= p->dist)
 		sides = 1;
-	if (dist2 < p->dist)
+	if (dist[1] < p->dist)
 		sides |= 2;
 
 	return sides;
 }
-#elif __GNUC__
-// use matha.s
-#else
-#pragma warning( disable: 4035 )
-
-__declspec( naked ) int BoxOnPlaneSide (vec3_t emins, vec3_t emaxs, struct cplane_s *p)
-{
-	static int bops_initialized;
-	static int Ljmptab[8];
-
-	__asm {
-
-		push ebx
-			
-		cmp bops_initialized, 1
-		je  initialized
-		mov bops_initialized, 1
-		
-		mov Ljmptab[0*4], offset Lcase0
-		mov Ljmptab[1*4], offset Lcase1
-		mov Ljmptab[2*4], offset Lcase2
-		mov Ljmptab[3*4], offset Lcase3
-		mov Ljmptab[4*4], offset Lcase4
-		mov Ljmptab[5*4], offset Lcase5
-		mov Ljmptab[6*4], offset Lcase6
-		mov Ljmptab[7*4], offset Lcase7
-			
-initialized:
-
-		mov edx,dword ptr[4+12+esp]
-		mov ecx,dword ptr[4+4+esp]
-		xor eax,eax
-		mov ebx,dword ptr[4+8+esp]
-		mov al,byte ptr[17+edx]
-		cmp al,8
-		jge Lerror
-		fld dword ptr[0+edx]
-		fld st(0)
-		jmp dword ptr[Ljmptab+eax*4]
-Lcase0:
-		fmul dword ptr[ebx]
-		fld dword ptr[0+4+edx]
-		fxch st(2)
-		fmul dword ptr[ecx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[4+ebx]
-		fld dword ptr[0+8+edx]
-		fxch st(2)
-		fmul dword ptr[4+ecx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[8+ebx]
-		fxch st(5)
-		faddp st(3),st(0)
-		fmul dword ptr[8+ecx]
-		fxch st(1)
-		faddp st(3),st(0)
-		fxch st(3)
-		faddp st(2),st(0)
-		jmp LSetSides
-Lcase1:
-		fmul dword ptr[ecx]
-		fld dword ptr[0+4+edx]
-		fxch st(2)
-		fmul dword ptr[ebx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[4+ebx]
-		fld dword ptr[0+8+edx]
-		fxch st(2)
-		fmul dword ptr[4+ecx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[8+ebx]
-		fxch st(5)
-		faddp st(3),st(0)
-		fmul dword ptr[8+ecx]
-		fxch st(1)
-		faddp st(3),st(0)
-		fxch st(3)
-		faddp st(2),st(0)
-		jmp LSetSides
-Lcase2:
-		fmul dword ptr[ebx]
-		fld dword ptr[0+4+edx]
-		fxch st(2)
-		fmul dword ptr[ecx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[4+ecx]
-		fld dword ptr[0+8+edx]
-		fxch st(2)
-		fmul dword ptr[4+ebx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[8+ebx]
-		fxch st(5)
-		faddp st(3),st(0)
-		fmul dword ptr[8+ecx]
-		fxch st(1)
-		faddp st(3),st(0)
-		fxch st(3)
-		faddp st(2),st(0)
-		jmp LSetSides
-Lcase3:
-		fmul dword ptr[ecx]
-		fld dword ptr[0+4+edx]
-		fxch st(2)
-		fmul dword ptr[ebx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[4+ecx]
-		fld dword ptr[0+8+edx]
-		fxch st(2)
-		fmul dword ptr[4+ebx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[8+ebx]
-		fxch st(5)
-		faddp st(3),st(0)
-		fmul dword ptr[8+ecx]
-		fxch st(1)
-		faddp st(3),st(0)
-		fxch st(3)
-		faddp st(2),st(0)
-		jmp LSetSides
-Lcase4:
-		fmul dword ptr[ebx]
-		fld dword ptr[0+4+edx]
-		fxch st(2)
-		fmul dword ptr[ecx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[4+ebx]
-		fld dword ptr[0+8+edx]
-		fxch st(2)
-		fmul dword ptr[4+ecx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[8+ecx]
-		fxch st(5)
-		faddp st(3),st(0)
-		fmul dword ptr[8+ebx]
-		fxch st(1)
-		faddp st(3),st(0)
-		fxch st(3)
-		faddp st(2),st(0)
-		jmp LSetSides
-Lcase5:
-		fmul dword ptr[ecx]
-		fld dword ptr[0+4+edx]
-		fxch st(2)
-		fmul dword ptr[ebx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[4+ebx]
-		fld dword ptr[0+8+edx]
-		fxch st(2)
-		fmul dword ptr[4+ecx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[8+ecx]
-		fxch st(5)
-		faddp st(3),st(0)
-		fmul dword ptr[8+ebx]
-		fxch st(1)
-		faddp st(3),st(0)
-		fxch st(3)
-		faddp st(2),st(0)
-		jmp LSetSides
-Lcase6:
-		fmul dword ptr[ebx]
-		fld dword ptr[0+4+edx]
-		fxch st(2)
-		fmul dword ptr[ecx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[4+ecx]
-		fld dword ptr[0+8+edx]
-		fxch st(2)
-		fmul dword ptr[4+ebx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[8+ecx]
-		fxch st(5)
-		faddp st(3),st(0)
-		fmul dword ptr[8+ebx]
-		fxch st(1)
-		faddp st(3),st(0)
-		fxch st(3)
-		faddp st(2),st(0)
-		jmp LSetSides
-Lcase7:
-		fmul dword ptr[ecx]
-		fld dword ptr[0+4+edx]
-		fxch st(2)
-		fmul dword ptr[ebx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[4+ecx]
-		fld dword ptr[0+8+edx]
-		fxch st(2)
-		fmul dword ptr[4+ebx]
-		fxch st(2)
-		fld st(0)
-		fmul dword ptr[8+ecx]
-		fxch st(5)
-		faddp st(3),st(0)
-		fmul dword ptr[8+ebx]
-		fxch st(1)
-		faddp st(3),st(0)
-		fxch st(3)
-		faddp st(2),st(0)
-LSetSides:
-		faddp st(2),st(0)
-		fcomp dword ptr[12+edx]
-		xor ecx,ecx
-		fnstsw ax
-		fcomp dword ptr[12+edx]
-		and ah,1
-		xor ah,1
-		add cl,ah
-		fnstsw ax
-		and ah,1
-		add ah,ah
-		add cl,ah
-		pop ebx
-		mov eax,ecx
-		ret
-Lerror:
-		int 3
-	}
-}
-#pragma warning( default: 4035 )
 
-#endif
 
 /*
 =================