power_play/src/base/base_shader.gh

////////////////////////////////////////////////////////////
//~ Base math types

#define Pi              ((f32)3.14159265358979323846)
#define Tau             ((f32)6.28318530717958647693)
#define GoldenRatio     ((f32)1.61803398874989484820)

typedef float2 Vec2;
typedef float3 Vec3;
typedef float4 Vec4;
typedef int2 Vec2I32;
typedef int3 Vec3I32;
typedef int4 Vec4I32;
typedef uint2 Vec2U32;
typedef uint3 Vec3U32;
typedef uint4 Vec4U32;
typedef float2x3 Xform;
typedef float4 Rect;
typedef float4 ClipRect;
typedef float4 Aabb;
typedef float4 Quad;
typedef float4x4 Mat4x4;

////////////////////////////////////////////////////////////
//~ Range types

Struct(Rng)    { f32 min; f32 max; };
Struct(RngI32) { i32 min; i32 max; };
Struct(RngU32) { u32 min; u32 max; };

Struct(Rng2)    { Vec2 p0;    Vec2 p1; };
Struct(Rng2I32) { Vec2I32 p0; Vec2I32 p1; };
Struct(Rng2U32) { Vec2U32 p0; Vec2U32 p1; };

Struct(Rng3)    { Vec3 p0;    Vec3 p1; };
Struct(Rng3I32) { Vec3I32 p0; Vec3I32 p1; };
Struct(Rng3U32) { Vec3U32 p0; Vec3U32 p1; };

////////////////////////////////////////////////////////////
//~ Countof

template<typename T, u32 N>
u32 countof(T arr[N])
{
  return N;
}

////////////////////////////////////////////////////////////
//~ Min / max

//- Min
#define MinU8(...) min(__VA_ARGS__)
#define MinI8(...) min(__VA_ARGS__)
#define MinU32(...) min(__VA_ARGS__)
#define MinI32(...) min(__VA_ARGS__)
#define MinF32(...) min(__VA_ARGS__)
#define MinU64(...) min(__VA_ARGS__)
#define MinI64(...) min(__VA_ARGS__)
#define MinF64(...) min(__VA_ARGS__)

//- Max
#define MaxU8(...) max(__VA_ARGS__)
#define MaxI8(...) max(__VA_ARGS__)
#define MaxU32(...) max(__VA_ARGS__)
#define MaxI32(...) max(__VA_ARGS__)
#define MaxF32(...) max(__VA_ARGS__)
#define MaxU64(...) max(__VA_ARGS__)
#define MaxI64(...) max(__VA_ARGS__)
#define MaxF64(...) max(__VA_ARGS__)

//- Clamp
#define ClampU32(...) clamp(__VA_ARGS__)
#define ClampI32(...) clamp(__VA_ARGS__)
#define ClampF32(...) clamp(__VA_ARGS__)
#define ClampU64(...) clamp(__VA_ARGS__)
#define ClampI64(...) clamp(__VA_ARGS__)
#define ClampF64(...) clamp(__VA_ARGS__)

////////////////////////////////////////////////////////////
//~ Color helpers

Vec4 Vec4FromU32(u32 v)
{
  Vec4 result;
  result.x = ((v >> 0) & 0xFF) / 255.0;
  result.y = ((v >> 8) & 0xFF) / 255.0;
  result.z = ((v >> 16) & 0xFF) / 255.0;
  result.w = ((v >> 24) & 0xFF) / 255.0;
  return result;
}

u32 U32FromVec4(Vec4 v)
{
  u32 result;
  result |= (((u32)(v.x * 255.0)) & 0xFF) << 0;
  result |= (((u32)(v.y * 255.0)) & 0xFF) << 8;
  result |= (((u32)(v.z * 255.0)) & 0xFF) << 16;
  result |= (((u32)(v.w * 255.0)) & 0xFF) << 24;
  return result;
}

f32 LinearFromSrgbF32(f32 srgb)
{
  f32 result;
  if (srgb <= 0.04045f)
  {
    result = srgb / 12.92f;
  }
  else
  {
    result = pow((srgb + 0.055f) / 1.055f, 2.4f);
  }
  return result;
}

Vec4 LinearFromSrgb(Vec4 srgb)
{
  Vec4 result;
  result.x = LinearFromSrgbF32(srgb.x);
  result.y = LinearFromSrgbF32(srgb.y);
  result.z = LinearFromSrgbF32(srgb.z);
  result.w = srgb.w;
  return result;
}

////////////////////////////////////////////////////////////
//~ Vertex ID helpers

Vec2 RectUvFromVertexId(u32 id)
{
  static const Vec2 uvs[4] = {
    Vec2(0, 0),
    Vec2(1, 0),
    Vec2(1, 1),
    Vec2(0, 1)
  };
  return uvs[id];
}

////////////////////////////////////////////////////////////
//~ Ndc helpers

Vec2 NdcFromPos(Vec2 pos, Vec2 size)
{
  Vec2 result;
  result = pos / size;
  result *= Vec2(2, -2);
  result += Vec2(-1, 1);
  return result;
}

Vec2 NdcFromUv(Vec2 uv)
{
  Vec2 result;
  result = uv;
  result *= Vec2(2, -2);
  result += Vec2(-1, 1);
  return result;
}

////////////////////////////////////////////////////////////
//~ String helpers

/* https://therealmjp.github.io/posts/hlsl-printf/ */
template<typename T>
u32 U32FromChar(in T c)
{
  if(c == ' ')
  return 32;
  if(c == '!')
  return 33;
  if(c == '\"' || c == '\"')
  return 34;
  if(c == '#')
  return 35;
  if(c == '$')
  return 36;
  if(c == '%')
  return 37;
  if(c == '&')
  return 38;
  if(c == '\'')
  return 39;
  if(c == '(')
  return 40;
  if(c == ')')
  return 41;
  if(c == '*')
  return 42;
  if(c == '+')
  return 43;
  if(c == ',')
  return 44;
  if(c == '-')
  return 45;
  if(c == '.')
  return 46;
  if(c == '/')
  return 47;
  if(c == '0')
  return 48;
  if(c == '1')
  return 49;
  if(c == '2')
  return 50;
  if(c == '3')
  return 51;
  if(c == '4')
  return 52;
  if(c == '5')
  return 53;
  if(c == '6')
  return 54;
  if(c == '7')
  return 55;
  if(c == '8')
  return 56;
  if(c == '9')
  return 57;
  if(c == ':')
  return 58;
  if(c == ';')
  return 59;
  if(c == '<')
  return 60;
  if(c == '=')
  return 61;
  if(c == '>')
  return 62;
  if(c == '?')
  return 63;
  if(c == '@')
  return 64;
  if(c == 'A')
  return 65;
  if(c == 'B')
  return 66;
  if(c == 'C')
  return 67;
  if(c == 'D')
  return 68;
  if(c == 'E')
  return 69;
  if(c == 'F')
  return 70;
  if(c == 'G')
  return 71;
  if(c == 'H')
  return 72;
  if(c == 'I')
  return 73;
  if(c == 'J')
  return 74;
  if(c == 'K')
  return 75;
  if(c == 'L')
  return 76;
  if(c == 'M')
  return 77;
  if(c == 'N')
  return 78;
  if(c == 'O')
  return 79;
  if(c == 'P')
  return 80;
  if(c == 'Q')
  return 81;
  if(c == 'R')
  return 82;
  if(c == 'S')
  return 83;
  if(c == 'T')
  return 84;
  if(c == 'U')
  return 85;
  if(c == 'V')
  return 86;
  if(c == 'W')
  return 87;
  if(c == 'X')
  return 88;
  if(c == 'Y')
  return 89;
  if(c == 'Z')
  return 90;
  if(c == '[')
  return 91;
  if(c == '\\')
  return 92;
  if(c == ']')
  return 93;
  if(c == '^')
  return 94;
  if(c == '_')
  return 95;
  if(c == '`')
  return 96;
  if(c == 'a')
  return 97;
  if(c == 'b')
  return 98;
  if(c == 'c')
  return 99;
  if(c == 'd')
  return 100;
  if(c == 'e')
  return 101;
  if(c == 'f')
  return 102;
  if(c == 'g')
  return 103;
  if(c == 'h')
  return 104;
  if(c == 'i')
  return 105;
  if(c == 'j')
  return 106;
  if(c == 'k')
  return 107;
  if(c == 'l')
  return 108;
  if(c == 'm')
  return 109;
  if(c == 'n')
  return 110;
  if(c == 'o')
  return 111;
  if(c == 'p')
  return 112;
  if(c == 'q')
  return 113;
  if(c == 'r')
  return 114;
  if(c == 's')
  return 115;
  if(c == 't')
  return 116;
  if(c == 'u')
  return 117;
  if(c == 'v')
  return 118;
  if(c == 'w')
  return 119;
  if(c == 'x')
  return 120;
  if(c == 'y')
  return 121;
  if(c == 'z')
  return 122;
  if(c == '{')
  return 123;
  if(c == '|')
  return 124;
  if(c == '}')
  return 125;
  if(c == '~')
  return 126;
  return 0;
}