all float3 and float4 functions and isas

completed all options of float3 and float4 functions in isas and math_c
neon still to be done but that will be on mac.

Engine/source/math/impl/math_c.cpp

@@ -0,0 +1,176 @@
+#include "math/public/float4_dispatch.h"
+#include "math/public/float3_dispatch.h"
+#include "math/mConstants.h"
+#include <cmath>   // for sqrtf, etc.
+
+namespace math_backend::float4::dispatch
+{
+   void install_scalar()
+   {
+      gFloat4.add = [](const float* a, const float* b, float* r) {
+         for (int i = 0; i < 4; i++) r[i] = a[i] + b[i];
+      };
+
+      gFloat4.sub = [](const float* a, const float* b, float* r) {
+         for (int i = 0; i < 4; i++) r[i] = a[i] - b[i];
+      };
+
+      gFloat4.mul = [](const float* a, const float* b, float* r) {
+         for (int i = 0; i < 4; i++) r[i] = a[i] * b[i];
+      };
+
+      gFloat4.mul_scalar = [](const float* a, float s, float* r) {
+         for (int i = 0; i < 4; i++) r[i] = a[i] * s;
+      };
+
+      gFloat4.div = [](const float* a, const float* b, float* r) {
+         for (int i = 0; i < 4; i++) r[i] = a[i] / b[i];
+      };
+
+      gFloat4.div_scalar = [](const float* a, float s, float* r) {
+         float denom = 1.0f / s;
+         for (int i = 0; i < 4; i++) r[i] = a[i] * denom;
+      };
+
+      gFloat4.dot = [](const float* a, const float* b) {
+         float sum = 0.f;
+         for (int i = 0; i < 4; i++) sum += a[i] * b[i];
+         return sum;
+      };
+
+      gFloat4.length = [](const float* a) {
+         float sum = 0.f;
+         for (int i = 0; i < 4; i++) sum += a[i] * a[i];
+         return std::sqrt(sum);
+      };
+
+      gFloat4.lengthSquared = [](const float* a) {
+         float sum = 0.f;
+         for (int i = 0; i < 4; i++) sum += a[i] * a[i];
+         return (sum);
+      };
+
+      gFloat4.normalize = [](float* a) {
+         float len = gFloat4.length(a);
+         if (len > POINT_EPSILON)
+         {
+            float denom = 1.0f / len;
+            for (int i = 0; i < 4; i++)
+               a[i] *= denom;
+         }
+      };
+
+      gFloat4.normalize_mag = [](float* a, float f) {
+         float len = gFloat4.length(a);
+         if (len > POINT_EPSILON)
+         {
+            float denom = f / len;
+            for (int i = 0; i < 4; i++) a[i] *= denom;
+         }
+      };
+
+      gFloat4.lerp = [](const float* from, const float* to, float f, float* r) {
+         for (int i = 0; i < 4; i++) r[i] = from[i] + (to[i] - from[i]) * f;
+      };
+
+      gFloat4.cross = [](const float* a, const float* b, float* r) {
+         const float ax = a[0];
+         const float ay = a[1];
+         const float az = a[2];
+
+         const float bx = b[0];
+         const float by = b[1];
+         const float bz = b[2];
+
+         r[0] = ay * bz - az * by;
+         r[1] = az * bx - ax * bz;
+         r[2] = ax * by - ay * bx;
+      };
+   }
+}
+
+namespace math_backend::float3::dispatch
+{
+   void install_scalar()
+   {
+      gFloat3.add = [](const float* a, const float* b, float* r) {
+         for (int i = 0; i < 3; i++) r[i] = a[i] + b[i];
+      };
+
+      gFloat3.sub = [](const float* a, const float* b, float* r) {
+         for (int i = 0; i < 3; i++) r[i] = a[i] - b[i];
+      };
+
+      gFloat3.mul = [](const float* a, const float* b, float* r) {
+         for (int i = 0; i < 3; i++) r[i] = a[i] * b[i];
+      };
+
+      gFloat3.mul_scalar = [](const float* a, float s, float* r) {
+         for (int i = 0; i < 3; i++) r[i] = a[i] * s;
+      };
+
+      gFloat3.div = [](const float* a, const float* b, float* r) {
+         for (int i = 0; i < 3; i++) r[i] = a[i] / b[i];
+      };
+
+      gFloat3.div_scalar = [](const float* a, float s, float* r) {
+         float denom = 1.0f / s;
+         for (int i = 0; i < 3; i++) r[i] = a[i] * denom;
+      };
+
+      gFloat3.dot = [](const float* a, const float* b) {
+         float sum = 0.f;
+         for (int i = 0; i < 3; i++) sum += a[i] * b[i];
+         return sum;
+      };
+
+      gFloat3.length = [](const float* a) {
+         float sum = 0.f;
+         for (int i = 0; i < 3; i++) sum += a[i] * a[i];
+         return std::sqrt(sum);
+      };
+
+      gFloat3.lengthSquared = [](const float* a) {
+         float sum = 0.f;
+         for (int i = 0; i < 3; i++) sum += a[i] * a[i];
+         return (sum);
+      };
+
+      gFloat3.normalize = [](float* a) {
+         float len = gFloat3.length(a);
+         if (len > POINT_EPSILON)
+         {
+            float denom = 1.0 / len;
+            for (int i = 0; i < 3; i++) a[i] *= denom;
+         }
+      };
+
+      gFloat3.normalize_mag = [](float* a, float f) {
+         float len = gFloat3.length(a);
+         if (len > POINT_EPSILON)
+         {
+            float denom = f / len;
+            for (int i = 0; i < 3; i++) a[i] *= denom;
+         }
+      };
+
+      gFloat3.lerp = [](const float* from, const float* to, float f, float* r) {
+         for (int i = 0; i < 3; i++) r[i] = from[i] + (to[i] - from[i]) * f;
+      };
+
+      gFloat3.cross = [](const float* a, const float* b, float* r) {
+         const float ax = a[0];
+         const float ay = a[1];
+         const float az = a[2];
+
+         const float bx = b[0];
+         const float by = b[1];
+         const float bz = b[2];
+
+         r[0] = ay * bz - az * by;
+         r[1] = az * bx - ax * bz;
+         r[2] = ax * by - ay * bx;
+      };
+   }
+}
+