PlayStation Development Network

Code: Select all

const auto x1y1 = perlin.noise2d(x1, y1),
           x0y0 = perlin.noise2d(x0, y0),
           ...;
                
mesh[meshIdx]   = {X+1  , x1y1, Z+1, 0};
mesh[meshIdx+1] = {X    , x0y0, Z  , 0};
mesh[meshIdx+2] = {X    , x0y1, Z+1, 0};

//calculate side2 - side1 for cross
const SVECTOR side1 = {mesh[meshIdx+1].vx - mesh[meshIdx].vx, mesh[meshIdx+1].vy - mesh[meshIdx].vy, mesh[meshIdx+1].vz - mesh[meshIdx].vz };
const SVECTOR side2 = {mesh[meshIdx+1].vx - mesh[meshIdx+2].vx, mesh[meshIdx+1].vy - mesh[meshIdx+2].vy, mesh[meshIdx+1].vz - mesh[meshIdx+2].vz };
                
normals[0] = MathUtils::cross(side1, side2);

mesh[meshIdx+3] = {X  , x0y0, Z,   0};
mesh[meshIdx+4] = {X+1, x1y1, Z+1, 0};
mesh[meshIdx+5] = {X+1, x1y0, Z,   0};

//calculate side4 - side3 for cross
const SVECTOR side3 = {mesh[meshIdx+4].vx - mesh[meshIdx+3].vx, mesh[meshIdx+4].vy - mesh[meshIdx+3].vy, mesh[meshIdx+4].vz - mesh[meshIdx+3].vz };
const SVECTOR side4 = {mesh[meshIdx+4].vx - mesh[meshIdx+5].vx, mesh[meshIdx+4].vy - mesh[meshIdx+5].vy, mesh[meshIdx+4].vz - mesh[meshIdx+5].vz };

normals[1] = MathUtils::cross(side3, side4);

Code: Select all

static constexpr SVECTOR cross(const SVECTOR& left, const SVECTOR& right)
{
    return {((left.vy*right.vz)-(left.vz*right.vy))>>12,
            ((left.vz*right.vx)-(left.vx*right.vz))>>12,
            ((left.vx*right.vy)-(left.vy*right.vx))>>12
    };
}