OpenClonk
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Properties Friends Macros
C4FoWAmbient.cpp
Go to the documentation of this file.
1 /*
2  * OpenClonk, http://www.openclonk.org
3  *
4  * Copyright (c) 2014-2016, The OpenClonk Team and contributors
5  *
6  * Distributed under the terms of the ISC license; see accompanying file
7  * "COPYING" for details.
8  *
9  * "Clonk" is a registered trademark of Matthes Bender, used with permission.
10  * See accompanying file "TRADEMARK" for details.
11  *
12  * To redistribute this file separately, substitute the full license texts
13  * for the above references.
14  */
15 
16 #include "C4Include.h"
19 #include "landscape/fow/C4FoW.h"
20 #include "graphics/C4Draw.h"
21 
22 namespace
23 {
24 
25 template<typename LightMap>
26 double AmbientForPix(int x0, int y0, double R, const LightMap& light_map)
27 {
28  double d = 0.;
29 
30  const int Ri = static_cast<int>(R);
31  for(int y = 1; y <= Ri; ++y)
32  {
33  // quarter circle
34  int max_x = static_cast<int>(sqrt(R * R - y * y));
35  for(int x = 1; x <= max_x; ++x)
36  {
37  const double l = sqrt(x*x + y*y);
38  assert(l <= R);
39 
40  if(light_map(x0 + x, y0 + y)) d += 1. / l;
41  if(light_map(x0 + x, y0 - y)) d += 1. / l;
42  if(light_map(x0 - x, y0 - y)) d += 1. / l;
43  if(light_map(x0 - x, y0 + y)) d += 1. / l;
44  }
45 
46  // Vertical/Horizontal lines
47  const double l = static_cast<double>(y);
48  if(light_map(x0 + y, y0)) d += 1. / l;
49  if(light_map(x0 - y, y0)) d += 1. / l;
50  if(light_map(x0, y0 + y)) d += 1. / l;
51  if(light_map(x0, y0 - y)) d += 1. / l;
52  }
53 
54  // Central pix
55  if(light_map(x0, y0)) d += 2 * sqrt(M_PI); // int_0^2pi int_0^1/sqrt(pi) 1/r dr r dphi
56 
57  return d;
58 }
59 
60 // Everything is illuminated, independent of the landscape
61 // This is used to obtain the normalization factor
62 struct LightMapFull {
63  LightMapFull() = default;
64  bool operator()(int x, int y) const { return true; }
65 };
66 
67 struct LightMapZoom {
68  LightMapZoom(const C4Landscape& landscape, double sx, double sy):
69  Landscape(landscape), sx(sx), sy(sy) {}
70 
71  // Returns whether zoomed coordinate is LightMap or not
72  bool operator()(int x, int y) const
73  {
74  // Landscape coordinates
75  const int lx = Clamp(static_cast<int>((x + 0.5) * sx), 0, Landscape.GetWidth() - 1);
76  const int ly = Clamp(static_cast<int>((y + 0.5) * sy), 0, Landscape.GetHeight() - 1);
77  // LightMap check
79  }
80 
81  const C4Landscape& Landscape;
82  const double sx;
83  const double sy;
84 };
85 
86 } // anonymous namespace
87 
88 C4FoWAmbient::C4FoWAmbient() = default;
89 
91 {
92  Clear();
93 }
94 
96 {
97 #ifndef USE_CONSOLE
98  if(Tex != 0) glDeleteTextures(1, &Tex);
99  Tex = 0;
100 #endif
101  Resolution = Radius = FullCoverage = 0.;
102  SizeX = SizeY = 0;
103  LandscapeX = LandscapeY = 0;
104  Brightness = 1.;
105 }
106 
107 void C4FoWAmbient::CreateFromLandscape(const C4Landscape& landscape, double resolution, double radius, double full_coverage)
108 {
109  assert(resolution >= 1.);
110  assert(radius >= 1.);
111  assert(full_coverage > 0 && full_coverage <= 1.);
112 
113  // Clear old map
114  Clear();
115 
116  Resolution = resolution;
117  Radius = radius;
118  FullCoverage = full_coverage;
119 
120  // Number of zoomed pixels
121  LandscapeX = Landscape.GetWidth();
122  LandscapeY = Landscape.GetHeight();
123  SizeX = std::min<unsigned int>(static_cast<unsigned int>(ceil(LandscapeX / resolution)), pDraw->MaxTexSize);
124  SizeY = std::min<unsigned int>(static_cast<unsigned int>(ceil(LandscapeY / resolution)), pDraw->MaxTexSize);
125 
126 #ifndef USE_CONSOLE
127  glGenTextures(1, &Tex);
128  glBindTexture(GL_TEXTURE_2D, Tex);
129  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
130  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
131  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
132  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
133  glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, SizeX, SizeY, 0, GL_RED, GL_FLOAT, nullptr);
134 
137  uint32_t dt = C4TimeMilliseconds::Now() - begin;
138  LogF("Created %ux%u ambient map in %g secs", SizeX, SizeY, dt / 1000.);
139 #endif
140 }
141 
142 void C4FoWAmbient::UpdateFromLandscape(const C4Landscape& landscape, const C4Rect& update)
143 {
144 #ifndef USE_CONSOLE
145  // Nothing to do?
146  if(update.Wdt == 0 || update.Hgt == 0) return;
147 
148  assert(Tex != 0);
149 
150  // Factor to go from zoomed to landscape coordinates
151  const double zoom_x = static_cast<double>(Landscape.GetWidth()) / SizeX;
152  const double zoom_y = static_cast<double>(Landscape.GetHeight()) / SizeY;
153  // Update region in zoomed coordinates
154  const unsigned int left = std::max(static_cast<int>( (update.x - Radius) / zoom_x), 0);
155  const unsigned int right = std::min(static_cast<unsigned int>( (update.x + update.Wdt + Radius) / zoom_x), SizeX - 1) + 1;
156  const unsigned int top = std::max(static_cast<int>( (update.y - Radius) / zoom_y), 0);
157  const unsigned int bottom = std::min(static_cast<unsigned int>( (update.y + update.Hgt + Radius) / zoom_y), SizeY - 1) + 1;
158  assert(right > left);
159  assert(bottom > top);
160  // Zoomed radius
161  const double R = Radius / sqrt(zoom_x * zoom_y);
162  // Normalization factor with the full circle
163  // The analytic result is 2*R*M_PI, and this number is typically close to it
164  const double norm = AmbientForPix(0, 0, R, LightMapFull()) * FullCoverage;
165  // Create the ambient map
166  LightMapZoom light_mapZoom(landscape, zoom_x, zoom_y);
167  float* ambient = new float[(right - left) * (bottom - top)];
168  for(unsigned int y = top; y < bottom; ++y)
169  {
170  for(unsigned int x = left; x < right; ++x)
171  {
172  ambient[(y - top) * (right - left) + (x - left)] = std::min(AmbientForPix(x, y, R, light_mapZoom) / norm, 1.0);
173  }
174  }
175 
176 #if 0
177  CSurface8 debug(SizeX, SizeY);
178  for(unsigned int y = 0; y < SizeY; ++y)
179  {
180  for(unsigned int x = 0; x < SizeX; ++x)
181  {
182  debug.SetPix(x, y, int(ambient[y * SizeX + x] * 255. + 0.5));
183  }
184  }
185 
186  CStdPalette pal;
187  for(int i = 0; i < 256; ++i)
188  pal.Colors[i] = i + (i << 8) + (i << 16);
189  debug.Save("Ambient.bmp", &pal);
190 #endif
191 
192  // Update the texture
193  glBindTexture(GL_TEXTURE_2D, Tex);
194  glTexSubImage2D(GL_TEXTURE_2D, 0, left, top, (right - left), (bottom - top), GL_RED, GL_FLOAT, ambient);
195  delete[] ambient;
196 #endif
197 }
198 
199 void C4FoWAmbient::GetFragTransform(const FLOAT_RECT& vpRect, const C4Rect& clipRect, const C4Rect& outRect, float ambientTransform[6]) const
200 {
201  C4FragTransform trans;
202  // Invert Y coordinate
203  trans.Scale(1, -1);
204  trans.Translate(0, outRect.Hgt);
205  // Clip offset
206  trans.Translate(-clipRect.x, -clipRect.y);
207  // Clip normalization (0,0 -> 1,1)
208  trans.Scale(1.0f / clipRect.Wdt, 1.0f / clipRect.Hgt);
209  // Viewport normalization
210  trans.Scale(vpRect.right - vpRect.left, vpRect.bottom - vpRect.top);
211  // Viewport offset
212  trans.Translate(vpRect.left, vpRect.top);
213  // Landscape normalization
214  trans.Scale(1.0f / LandscapeX, 1.0f / LandscapeY);
215 
216  // Extract matrix
217  trans.Get2x3(ambientTransform);
218 }
int MaxTexSize
Definition: C4Draw.h:99
void Translate(float dx, float dy)
Definition: C4FoW.h:38
float bottom
Definition: C4Rect.h:25
float right
Definition: C4Rect.h:25
float left
Definition: C4Rect.h:25
void UpdateFromLandscape(const C4Landscape &landscape, const C4Rect &update)
DWORD Colors[256]
Definition: StdColors.h:184
void CreateFromLandscape(const C4Landscape &landscape, double resolution, double radius, double full_coverage)
Definition: C4Rect.h:27
T Clamp(T bval, T lbound, T rbound)
Definition: Standard.h:44
int32_t Wdt
Definition: C4Rect.h:30
void Scale(float sx, float sy)
Definition: C4FoW.h:45
int32_t y
Definition: C4Rect.h:30
C4Landscape Landscape
C4Draw * pDraw
Definition: C4Draw.cpp:42
int32_t x
Definition: C4Rect.h:30
int32_t GetHeight() const
void Get2x3(float transform[6])
Definition: C4FoW.h:54
int32_t Hgt
Definition: C4Rect.h:30
void SetPix(int iX, int iY, BYTE byCol)
Definition: CSurface8.h:37
bool Save(const char *szFilename, CStdPalette *=nullptr)
Definition: CSurface8.cpp:158
bool LogF(const char *strMessage,...)
Definition: C4Log.cpp:250
bool _GetLight(int32_t x, int32_t y)
float top
Definition: C4Rect.h:25
static C4TimeMilliseconds Now()
int32_t GetWidth() const
void GetFragTransform(const struct FLOAT_RECT &vpRect, const C4Rect &clipRect, const C4Rect &outRect, float ambientTransform[6]) const