metaforce/Runtime/World/CFluidPlane.hpp

#pragma once

#include <algorithm>
#include <cmath>
#include <optional>
#include <vector>

#include "Runtime/CToken.hpp"
#include "Runtime/RetroTypes.hpp"
#include "Runtime/Graphics/CTexture.hpp"
#include "Runtime/Graphics/Shaders/CFluidPlaneShader.hpp"
#include "Runtime/World/CFluidUVMotion.hpp"

#include <zeus/CAABox.hpp>
#include <zeus/CColor.hpp>
#include <zeus/CFrustum.hpp>
#include <zeus/CVector2f.hpp>

namespace urde {
class CFluidUVMotion;
class CRipple;
class CRippleManager;
class CScriptWater;
class CStateManager;

class CFluidPlaneRender {
public:
  enum class NormalMode { None, NoNormals, Normals, NBT };

  static int numTilesInHField;
  static int numSubdivisionsInTile;
  static int numSubdivisionsInHField;

  struct SPatchInfo {
    u8 x0_xSubdivs, x1_ySubdivs;
    zeus::CVector2f x4_localMin, xc_globalMin;
    float x14_tileSize;
    float x18_rippleResolution;
    float x1c_tileHypRadius;
    float x20_ooTileSize;
    float x24_ooRippleResolution;
    u16 x28_tileX;
    u16 x2a_gridDimX;
    u16 x2c_gridDimY;
    u16 x2e_tileY;
    const bool* x30_gridFlags;
    u8 x34_redShift;
    u8 x35_greenShift;
    u8 x36_blueShift;
    NormalMode x37_normalMode;
    float x38_wavecapIntensityScale;

  public:
    SPatchInfo(const zeus::CVector3f& localMin, const zeus::CVector3f& localMax, const zeus::CVector3f& pos,
               float rippleResolution, float tileSize, float wavecapIntensityScale, int numSubdivisionsInHField,
               NormalMode normalMode, int redShift, int greenShift, int blueShift, u32 tileX, u32 gridDimX,
               u32 gridDimY, u32 tileY, const bool* gridFlags) {
      x0_xSubdivs = std::min(s16((localMax.x() - localMin.x()) / rippleResolution + 1.f - FLT_EPSILON) + 2,
                             numSubdivisionsInHField + 2);
      x1_ySubdivs = std::min(s16((localMax.y() - localMin.y()) / rippleResolution + 1.f - FLT_EPSILON) + 2,
                             numSubdivisionsInHField + 2);
      float tileHypRadius = tileSize * tileSize * 2 * 0.25f;
      x4_localMin = localMin.toVec2f();
      xc_globalMin = x4_localMin + pos.toVec2f();
      x14_tileSize = tileSize;
      x18_rippleResolution = rippleResolution;
      if (tileHypRadius != 0.f)
        tileHypRadius = std::sqrt(tileHypRadius);
      x1c_tileHypRadius = tileHypRadius;
      x20_ooTileSize = 1.f / x14_tileSize;
      x24_ooRippleResolution = 1.f / x18_rippleResolution;
      x28_tileX = u16(tileX);
      x2a_gridDimX = u16(gridDimX);
      x2c_gridDimY = u16(gridDimY);
      x2e_tileY = u16(tileY);
      x30_gridFlags = gridFlags;
      x34_redShift = u8(redShift);
      x35_greenShift = u8(greenShift);
      x36_blueShift = u8(blueShift);
      x37_normalMode = normalMode;
      x38_wavecapIntensityScale = wavecapIntensityScale;
    }
  };

  struct SRippleInfo {
    const CRipple& x0_ripple;
    int x4_fromX;
    int x8_toX;
    int xc_fromY;
    int x10_toY;
    int x14_gfromX;
    int x18_gtoX;
    int x1c_gfromY;
    int x20_gtoY;

  public:
    SRippleInfo(const CRipple& ripple, int fromX, int toX, int fromY, int toY)
    : x0_ripple(ripple), x14_gfromX(fromX), x18_gtoX(toX), x1c_gfromY(fromY), x20_gtoY(toY) {}
  };

  struct SHFieldSample {
    float height;
    s8 nx;
    s8 ny;
    s8 nz;
    u8 wavecapIntensity;

    zeus::CVector3f MakeNormal() const { return zeus::CVector3f{nx / 63.f, ny / 63.f, nz / 63.f}.normalized(); }
    zeus::CVector3f MakeBinormal() const { return zeus::CVector3f{nx / 63.f, nz / 63.f, -ny / 63.f}.normalized(); }
    zeus::CVector3f MakeTangent() const { return zeus::CVector3f{nz / 63.f, ny / 63.f, -nx / 63.f}.normalized(); }
    zeus::CColor MakeColor(const CFluidPlaneRender::SPatchInfo& info) const {
      return {(wavecapIntensity >> info.x34_redShift) / 255.f, (wavecapIntensity >> info.x35_greenShift) / 255.f,
              (wavecapIntensity >> info.x36_blueShift) / 255.f};
    }
  };
};

class CFluidPlane {
protected:
  CAssetId x4_texPattern1Id;
  CAssetId x8_texPattern2Id;
  CAssetId xc_texColorId;
  TLockedToken<CTexture> x10_texPattern1;
  TLockedToken<CTexture> x20_texPattern2;
  TLockedToken<CTexture> x30_texColor;
  float x40_alpha;
  EFluidType x44_fluidType;
  float x48_rippleIntensity;
  CFluidUVMotion x4c_uvMotion;

  mutable std::vector<CFluidPlaneShader::Vertex> m_verts;
  mutable std::vector<CFluidPlaneShader::PatchVertex> m_pVerts;
  mutable std::optional<CFluidPlaneShader> m_shader;

  float ProjectRippleVelocity(float baseI, float velDot) const;
  float CalculateRippleIntensity(float baseI) const;

  virtual void RenderStripWithRipples(float curY, const CFluidPlaneRender::SHFieldSample (&heights)[46][46],
                                      const u8 (&flags)[9][9], int startYDiv, const CFluidPlaneRender::SPatchInfo& info,
                                      std::vector<CFluidPlaneShader::Vertex>& vOut,
                                      std::vector<CFluidPlaneShader::PatchVertex>& pvOut) const;
  void RenderPatch(const CFluidPlaneRender::SPatchInfo& info, const CFluidPlaneRender::SHFieldSample (&heights)[46][46],
                   const u8 (&flags)[9][9], bool noRipples, bool flagIs1, std::vector<CFluidPlaneShader::Vertex>& vOut,
                   std::vector<CFluidPlaneShader::PatchVertex>& pvOut) const;

public:
  virtual ~CFluidPlane() = default;
  CFluidPlane(CAssetId texPattern1, CAssetId texPattern2, CAssetId texColor, float alpha, EFluidType fluidType,
              float rippleIntensity, const CFluidUVMotion& motion);

  // Called by CPlayer, CMorphBall, CWeapon, CPuddleSpore, CMagdolite
  virtual void AddRipple(float mag, TUniqueId rippler, const zeus::CVector3f& center, CScriptWater& water,
                         CStateManager& mgr);

  // Called by CAi
  virtual void AddRipple(float intensity, TUniqueId rippler, const zeus::CVector3f& center,
                         const zeus::CVector3f& velocity, const CScriptWater& water, CStateManager& mgr,
                         const zeus::CVector3f& upVec);

  virtual void AddRipple(const CRipple& ripple, const CScriptWater& water, CStateManager& mgr);

  virtual void Render(const CStateManager& mgr, float alpha, const zeus::CAABox& aabb, const zeus::CTransform& xf,
                      const zeus::CTransform& areaXf, bool noNormals, const zeus::CFrustum& frustum,
                      const std::optional<CRippleManager>& rippleManager, TUniqueId waterId,
                      const bool* gridFlags, u32 gridDimX, u32 gridDimY, const zeus::CVector3f& areaCenter) const {}

  float GetAlpha() const { return x40_alpha; }
  EFluidType GetFluidType() const { return x44_fluidType; }
  const CFluidUVMotion& GetUVMotion() const { return x4c_uvMotion; }
  const CTexture& GetColorTexture() const { return *x30_texColor; }
  bool HasColorTexture() const { return x30_texColor.operator bool(); }
  const CTexture& GetTexturePattern1() const { return *x10_texPattern1; }
  bool HasTexturePattern1() const { return x10_texPattern1.operator bool(); }
  const CTexture& GetTexturePattern2() const { return *x20_texPattern2; }
  bool HasTexturePattern2() const { return x20_texPattern2.operator bool(); }
};
} // namespace urde