X-Git-Url: http://de.git.xonotic.org/?p=xonotic%2Fdarkplaces.git;a=blobdiff_plain;f=mathlib.h;h=ba362ce32b4262c9b27d3ed19b791e83b19db278;hp=c4d82865532b6bdffbccdbb9845c8fa452664b15;hb=2861288617172d7be2fc45c92b3bc1adb04f8a2a;hpb=86a799933460c0c03cad9a7d3b7a7e5f7624af6b

diff --git a/mathlib.h b/mathlib.h
index c4d82865..ba362ce3 100644
--- a/mathlib.h
+++ b/mathlib.h
@@ -51,6 +51,8 @@ extern vec3_t vec3_origin;
 
 #define lhrandom(MIN,MAX) ((rand() & 32767) * (((MAX)-(MIN)) * (1.0f / 32767.0f)) + (MIN))
 
+#define invpow(base,number) (log(number) / log(base))
+
 #define DEG2RAD(a) ((a) * ((float) M_PI / 180.0f))
 #define RAD2DEG(a) ((a) * (180.0f / (float) M_PI))
 #define ANGLEMOD(a) (((int) ((a) * (65536.0f / 360.0f)) & 65535) * (360.0f / 65536.0f))
@@ -62,6 +64,7 @@ extern vec3_t vec3_origin;
 #define VectorSubtract(a,b,c) ((c)[0]=(a)[0]-(b)[0],(c)[1]=(a)[1]-(b)[1],(c)[2]=(a)[2]-(b)[2])
 #define VectorAdd(a,b,c) ((c)[0]=(a)[0]+(b)[0],(c)[1]=(a)[1]+(b)[1],(c)[2]=(a)[2]+(b)[2])
 #define VectorCopy(a,b) ((b)[0]=(a)[0],(b)[1]=(a)[1],(b)[2]=(a)[2])
+#define VectorMultiply(a,b,c) ((c)[0]=(a)[0]*(b)[0],(c)[1]=(a)[1]*(b)[1],(c)[2]=(a)[2]*(b)[2])
 #define CrossProduct(a,b,c) ((c)[0]=(a)[1]*(b)[2]-(a)[2]*(b)[1],(c)[1]=(a)[2]*(b)[0]-(a)[0]*(b)[2],(c)[2]=(a)[0]*(b)[1]-(a)[1]*(b)[0])
 #define VectorNormalize(v) {float ilength = (float) sqrt(DotProduct(v,v));if (ilength) ilength = 1.0f / ilength;v[0] *= ilength;v[1] *= ilength;v[2] *= ilength;}
 #define VectorNormalize2(v,dest) {float ilength = (float) sqrt(DotProduct(v,v));if (ilength) ilength = 1.0f / ilength;dest[0] = v[0] * ilength;dest[1] = v[1] * ilength;dest[2] = v[2] * ilength;}
@@ -89,6 +92,39 @@ extern vec3_t vec3_origin;
 }
 #define VectorRandom(v) do{(v)[0] = lhrandom(-1, 1);(v)[1] = lhrandom(-1, 1);(v)[2] = lhrandom(-1, 1);}while(DotProduct(v, v) > 1)
 #define VectorBlend(b1, b2, blend, c) do{float iblend = 1 - (blend);VectorMAM(iblend, b1, blend, b2, c);}while(0)
+#define BoxesOverlap(a,b,c,d) ((a)[0] <= (d)[0] && (b)[0] >= (c)[0] && (a)[1] <= (d)[1] && (b)[1] >= (c)[1] && (a)[2] <= (d)[2] && (b)[2] >= (c)[2])
+
+// fast PointInfrontOfTriangle
+// subtracts v1 from v0 and v2, combined into a crossproduct, combined with a
+// dotproduct of the light location relative to the first point of the
+// triangle (any point works, since any triangle is obviously flat), and
+// finally a comparison to determine if the light is infront of the triangle
+// (the goal of this statement) we do not need to normalize the surface
+// normal because both sides of the comparison use it, therefore they are
+// both multiplied the same amount...  furthermore the subtract can be done
+// on the vectors, saving a little bit of math in the dotproducts
+#define PointInfrontOfTriangle(p,a,b,c) (((p)[0] - (a)[0]) * (((a)[1] - (b)[1]) * ((c)[2] - (b)[2]) - ((a)[2] - (b)[2]) * ((c)[1] - (b)[1])) + ((p)[1] - (a)[1]) * (((a)[2] - (b)[2]) * ((c)[0] - (b)[0]) - ((a)[0] - (b)[0]) * ((c)[2] - (b)[2])) + ((p)[2] - (a)[2]) * (((a)[0] - (b)[0]) * ((c)[1] - (b)[1]) - ((a)[1] - (b)[1]) * ((c)[0] - (b)[0])) > 0)
+#if 0
+// readable version, kept only for explanatory reasons
+int PointInfrontOfTriangle(const float *p, const float *a, const float *b, const float *c)
+{
+	float dir0[3], dir1[3], normal[3];
+
+	// calculate two mostly perpendicular edge directions
+	VectorSubtract(a, b, dir0);
+	VectorSubtract(c, b, dir1);
+
+	// we have two edge directions, we can calculate a third vector from
+	// them, which is the direction of the surface normal (it's magnitude
+	// is not 1 however)
+	CrossProduct(dir0, dir1, normal);
+
+	// compare distance of light along normal, with distance of any point
+	// of the triangle along the same normal (the triangle is planar,
+	// I.E. flat, so all points give the same answer)
+	return DotProduct(p, normal) > DotProduct(a, normal);
+}
+#endif
 
 /*
 // LordHavoc: quaternion math, untested, don't know if these are correct,
@@ -181,9 +217,13 @@ tinydoubleplane_t;
 
 void RotatePointAroundVector(vec3_t dst, const vec3_t dir, const vec3_t point, float degrees);
 
+float RadiusFromBounds (const vec3_t mins, const vec3_t maxs);
+float RadiusFromBoundsAndOrigin (const vec3_t mins, const vec3_t maxs, const vec3_t origin);
+
 // print a matrix to the console
 struct matrix4x4_s;
 void Matrix4x4_Print(const struct matrix4x4_s *in);
+int Math_atov(const char *s, vec3_t out);
 
 #endif