src/graphics/shader.cpp

   1 #include "BlendedSprite.hpp"
   2 #include "BlockLighting.hpp"
   3 #include "DirectionalLighting.hpp"
   4 #include "Program.hpp"
   5 #include "Shader.hpp"
   6
   7 #include "Texture.hpp"
   8 #include "../app/init.hpp"
   9
  10 #include <algorithm>
  11 #include <iostream>
  12 #include <memory>
  13 #include <ostream>
  14 #include <stdexcept>
  15 #include <string>
  16
  17
  18 namespace {
  19
  20 void gl_error(std::string msg) {
  21         const GLubyte *errBegin = gluErrorString(glGetError());
  22         if (errBegin && *errBegin != '\0') {
  23                 const GLubyte *errEnd = errBegin;
  24                 while (*errEnd != '\0') {
  25                         ++errEnd;
  26                 }
  27                 msg += ": ";
  28                 msg.append(errBegin, errEnd);
  29         }
  30         throw std::runtime_error(msg);
  31 }
  32
  33 }
  34
  35 namespace blank {
  36
  37 Shader::Shader(GLenum type)
  38 : handle(glCreateShader(type)) {
  39         if (handle == 0) {
  40                 gl_error("glCreateShader");
  41         }
  42 }
  43
  44 Shader::~Shader() {
  45         if (handle != 0) {
  46                 glDeleteShader(handle);
  47         }
  48 }
  49
  50 Shader::Shader(Shader &&other) noexcept
  51 : handle(other.handle) {
  52         other.handle = 0;
  53 }
  54
  55 Shader &Shader::operator =(Shader &&other) noexcept {
  56         std::swap(handle, other.handle);
  57         return *this;
  58 }
  59
  60
  61 void Shader::Source(const GLchar *src) noexcept {
  62         const GLchar* src_arr[] = { src };
  63         glShaderSource(handle, 1, src_arr, nullptr);
  64 }
  65
  66 void Shader::Compile() noexcept {
  67         glCompileShader(handle);
  68 }
  69
  70 bool Shader::Compiled() const noexcept {
  71         GLint compiled = GL_FALSE;
  72         glGetShaderiv(handle, GL_COMPILE_STATUS, &compiled);
  73         return compiled == GL_TRUE;
  74 }
  75
  76 void Shader::Log(std::ostream &out) const {
  77         int log_len = 0, max_len = 0;
  78         glGetShaderiv(handle, GL_INFO_LOG_LENGTH, &max_len);
  79         std::unique_ptr<char[]> log(new char[max_len]);
  80         glGetShaderInfoLog(handle, max_len, &log_len, log.get());
  81         out.write(log.get(), log_len);
  82 }
  83
  84
  85 void Shader::AttachToProgram(GLuint id) const noexcept {
  86         glAttachShader(id, handle);
  87 }
  88
  89
  90 Program::Program()
  91 : handle(glCreateProgram()) {
  92         if (handle == 0) {
  93                 gl_error("glCreateProgram");
  94         }
  95 }
  96
  97 Program::~Program() {
  98         if (handle != 0) {
  99                 glDeleteProgram(handle);
 100         }
 101 }
 102
 103
 104 const Shader &Program::LoadShader(GLenum type, const GLchar *src) {
 105         shaders.emplace_back(type);
 106         Shader &shader = shaders.back();
 107         shader.Source(src);
 108         shader.Compile();
 109         if (!shader.Compiled()) {
 110                 shader.Log(std::cerr);
 111                 throw std::runtime_error("compile shader");
 112         }
 113         Attach(shader);
 114         return shader;
 115 }
 116
 117 void Program::Attach(Shader &shader) noexcept {
 118         shader.AttachToProgram(handle);
 119 }
 120
 121 void Program::Link() noexcept {
 122         glLinkProgram(handle);
 123 }
 124
 125 bool Program::Linked() const noexcept {
 126         GLint linked = GL_FALSE;
 127         glGetProgramiv(handle, GL_LINK_STATUS, &linked);
 128         return linked == GL_TRUE;
 129 }
 130
 131 void Program::Log(std::ostream &out) const {
 132         int log_len = 0, max_len = 0;
 133         glGetProgramiv(handle, GL_INFO_LOG_LENGTH, &max_len);
 134         std::unique_ptr<char[]> log(new char[max_len]);
 135         glGetProgramInfoLog(handle, max_len, &log_len, log.get());
 136         out.write(log.get(), log_len);
 137 }
 138
 139
 140 GLint Program::AttributeLocation(const GLchar *name) const noexcept {
 141         return glGetAttribLocation(handle, name);
 142 }
 143
 144 GLint Program::UniformLocation(const GLchar *name) const noexcept {
 145         return glGetUniformLocation(handle, name);
 146 }
 147
 148
 149 DirectionalLighting::DirectionalLighting()
 150 : program()
 151 , light_direction(1.0f, 3.0f, 2.0f)
 152 , light_color(0.9f, 0.9f, 0.9f)
 153 , vp(1.0f)
 154 , m_handle(0)
 155 , mv_handle(0)
 156 , mvp_handle(0)
 157 , light_direction_handle(0)
 158 , light_color_handle(0)
 159 , fog_density_handle(0) {
 160         program.LoadShader(
 161                 GL_VERTEX_SHADER,
 162                 "#version 330 core\n"
 163                 "layout(location = 0) in vec3 vtx_position;\n"
 164                 "layout(location = 1) in vec3 vtx_color;\n"
 165                 "layout(location = 2) in vec3 vtx_normal;\n"
 166                 "uniform mat4 M;\n"
 167                 "uniform mat4 MV;\n"
 168                 "uniform mat4 MVP;\n"
 169                 "out vec3 frag_color;\n"
 170                 "out vec3 vtx_viewspace;\n"
 171                 "out vec3 normal;\n"
 172                 "void main() {\n"
 173                         "gl_Position = MVP * vec4(vtx_position, 1);\n"
 174                         "vtx_viewspace = (MV * vec4(vtx_position, 1)).xyz;\n"
 175                         "normal = (M * vec4(vtx_normal, 0)).xyz;\n"
 176                         "frag_color = vtx_color;\n"
 177                 "}\n"
 178         );
 179         program.LoadShader(
 180                 GL_FRAGMENT_SHADER,
 181                 "#version 330 core\n"
 182                 "in vec3 frag_color;\n"
 183                 "in vec3 vtx_viewspace;\n"
 184                 "in vec3 normal;\n"
 185                 "uniform vec3 light_direction;\n"
 186                 "uniform vec3 light_color;\n"
 187                 "uniform float fog_density;\n"
 188                 "out vec3 color;\n"
 189                 "void main() {\n"
 190                         "vec3 ambient = vec3(0.1, 0.1, 0.1) * frag_color;\n"
 191                         // this should be the same as the clear color, otherwise looks really weird
 192                         "vec3 fog_color = vec3(0, 0, 0);\n"
 193                         "float e = 2.718281828;\n"
 194                         "vec3 n = normalize(normal);\n"
 195                         "vec3 l = normalize(light_direction);\n"
 196                         "float cos_theta = clamp(dot(n, l), 0, 1);\n"
 197                         "vec3 reflect_color = ambient + frag_color * light_color * cos_theta;\n"
 198                         "float value = pow(e, -pow(fog_density * length(vtx_viewspace), 5));"
 199                         "color = mix(fog_color, reflect_color, value);\n"
 200                 "}\n"
 201         );
 202         program.Link();
 203         if (!program.Linked()) {
 204                 program.Log(std::cerr);
 205                 throw std::runtime_error("link program");
 206         }
 207
 208         m_handle = program.UniformLocation("M");
 209         mv_handle = program.UniformLocation("MV");
 210         mvp_handle = program.UniformLocation("MVP");
 211         light_direction_handle = program.UniformLocation("light_direction");
 212         light_color_handle = program.UniformLocation("light_color");
 213         fog_density_handle = program.UniformLocation("fog_density");
 214 }
 215
 216
 217 void DirectionalLighting::Activate() noexcept {
 218         program.Use();
 219
 220         glUniform3f(light_direction_handle, light_direction.x, light_direction.y, light_direction.z);
 221         glUniform3f(light_color_handle, light_color.x, light_color.y, light_color.z);
 222 }
 223
 224 void DirectionalLighting::SetM(const glm::mat4 &m) noexcept {
 225         glm::mat4 mv(view * m);
 226         glm::mat4 mvp(vp * m);
 227         glUniformMatrix4fv(m_handle, 1, GL_FALSE, &m[0][0]);
 228         glUniformMatrix4fv(mv_handle, 1, GL_FALSE, &mv[0][0]);
 229         glUniformMatrix4fv(mvp_handle, 1, GL_FALSE, &mvp[0][0]);
 230 }
 231
 232 void DirectionalLighting::SetLightDirection(const glm::vec3 &dir) noexcept {
 233         light_direction = -dir;
 234         glUniform3f(light_direction_handle, light_direction.x, light_direction.y, light_direction.z);
 235 }
 236
 237 void DirectionalLighting::SetFogDensity(float f) noexcept {
 238         fog_density = f;
 239         glUniform1f(fog_density_handle, fog_density);
 240 }
 241
 242 void DirectionalLighting::SetProjection(const glm::mat4 &p) noexcept {
 243         projection = p;
 244         vp = p * view;
 245 }
 246
 247 void DirectionalLighting::SetView(const glm::mat4 &v) noexcept {
 248         view = v;
 249         vp = projection * v;
 250 }
 251
 252 void DirectionalLighting::SetVP(const glm::mat4 &v, const glm::mat4 &p) noexcept {
 253         projection = p;
 254         view = v;
 255         vp = p * v;
 256 }
 257
 258 void DirectionalLighting::SetMVP(const glm::mat4 &m, const glm::mat4 &v, const glm::mat4 &p) noexcept {
 259         SetVP(v, p);
 260         SetM(m);
 261 }
 262
 263
 264 BlockLighting::BlockLighting()
 265 : program()
 266 , vp(1.0f)
 267 , mv_handle(0)
 268 , mvp_handle(0)
 269 , fog_density_handle(0) {
 270         program.LoadShader(
 271                 GL_VERTEX_SHADER,
 272                 "#version 330 core\n"
 273                 "layout(location = 0) in vec3 vtx_position;\n"
 274                 "layout(location = 1) in vec3 vtx_color;\n"
 275                 "layout(location = 2) in float vtx_light;\n"
 276                 "uniform mat4 MV;\n"
 277                 "uniform mat4 MVP;\n"
 278                 "out vec3 frag_color;\n"
 279                 "out vec3 vtx_viewspace;\n"
 280                 "out float frag_light;\n"
 281                 "void main() {\n"
 282                         "gl_Position = MVP * vec4(vtx_position, 1);\n"
 283                         "frag_color = vtx_color;\n"
 284                         "vtx_viewspace = (MV * vec4(vtx_position, 1)).xyz;\n"
 285                         "frag_light = vtx_light;\n"
 286                 "}\n"
 287         );
 288         program.LoadShader(
 289                 GL_FRAGMENT_SHADER,
 290                 "#version 330 core\n"
 291                 "in vec3 frag_color;\n"
 292                 "in vec3 vtx_viewspace;\n"
 293                 "in float frag_light;\n"
 294                 "uniform float fog_density;\n"
 295                 "out vec3 color;\n"
 296                 "void main() {\n"
 297                         "vec3 ambient = vec3(0.1, 0.1, 0.1) * frag_color;\n"
 298                         "float light_power = clamp(pow(0.8, 15 - frag_light), 0, 1);\n"
 299                         "vec3 fog_color = vec3(0, 0, 0);\n"
 300                         "float e = 2.718281828;\n"
 301                         //"vec3 reflect_color = ambient + frag_color * light_power;\n"
 302                         "vec3 reflect_color = frag_color * light_power;\n"
 303                         "float value = pow(e, -pow(fog_density * length(vtx_viewspace), 5));"
 304                         "color = mix(fog_color, reflect_color, value);\n"
 305                 "}\n"
 306         );
 307         program.Link();
 308         if (!program.Linked()) {
 309                 program.Log(std::cerr);
 310                 throw std::runtime_error("link program");
 311         }
 312
 313         mv_handle = program.UniformLocation("MV");
 314         mvp_handle = program.UniformLocation("MVP");
 315         fog_density_handle = program.UniformLocation("fog_density");
 316 }
 317
 318
 319 void BlockLighting::Activate() noexcept {
 320         program.Use();
 321 }
 322
 323 void BlockLighting::SetM(const glm::mat4 &m) noexcept {
 324         glm::mat4 mv(view * m);
 325         glm::mat4 mvp(vp * m);
 326         glUniformMatrix4fv(mv_handle, 1, GL_FALSE, &mv[0][0]);
 327         glUniformMatrix4fv(mvp_handle, 1, GL_FALSE, &mvp[0][0]);
 328 }
 329
 330 void BlockLighting::SetFogDensity(float f) noexcept {
 331         fog_density = f;
 332         glUniform1f(fog_density_handle, fog_density);
 333 }
 334
 335 void BlockLighting::SetProjection(const glm::mat4 &p) noexcept {
 336         projection = p;
 337         vp = p * view;
 338 }
 339
 340 void BlockLighting::SetView(const glm::mat4 &v) noexcept {
 341         view = v;
 342         vp = projection * v;
 343 }
 344
 345 void BlockLighting::SetVP(const glm::mat4 &v, const glm::mat4 &p) noexcept {
 346         projection = p;
 347         view = v;
 348         vp = p * v;
 349 }
 350
 351 void BlockLighting::SetMVP(const glm::mat4 &m, const glm::mat4 &v, const glm::mat4 &p) noexcept {
 352         SetVP(v, p);
 353         SetM(m);
 354 }
 355
 356
 357 BlendedSprite::BlendedSprite()
 358 : program()
 359 , vp(1.0f)
 360 , mvp_handle(0)
 361 , sampler_handle(0) {
 362         program.LoadShader(
 363                 GL_VERTEX_SHADER,
 364                 "#version 330 core\n"
 365                 "layout(location = 0) in vec3 vtx_position;\n"
 366                 "layout(location = 1) in vec2 vtx_tex_uv;\n"
 367                 "uniform mat4 MVP;\n"
 368                 "out vec2 frag_tex_uv;\n"
 369                 "void main() {\n"
 370                         "gl_Position = MVP * vec4(vtx_position, 1);\n"
 371                         "frag_tex_uv = vtx_tex_uv;\n"
 372                 "}\n"
 373         );
 374         program.LoadShader(
 375                 GL_FRAGMENT_SHADER,
 376                 "#version 330 core\n"
 377                 "in vec2 frag_tex_uv;\n"
 378                 "uniform sampler2D tex_sampler;\n"
 379                 "out vec4 color;\n"
 380                 "void main() {\n"
 381                         "color = texture(tex_sampler, frag_tex_uv);\n"
 382                 "}\n"
 383         );
 384         program.Link();
 385         if (!program.Linked()) {
 386                 program.Log(std::cerr);
 387                 throw std::runtime_error("link program");
 388         }
 389
 390         mvp_handle = program.UniformLocation("MVP");
 391         sampler_handle = program.UniformLocation("tex_sampler");
 392 }
 393
 394
 395 void BlendedSprite::Activate() noexcept {
 396         program.Use();
 397 }
 398
 399 void BlendedSprite::SetM(const glm::mat4 &m) noexcept {
 400         glm::mat4 mvp(vp * m);
 401         glUniformMatrix4fv(mvp_handle, 1, GL_FALSE, &mvp[0][0]);
 402 }
 403
 404 void BlendedSprite::SetProjection(const glm::mat4 &p) noexcept {
 405         projection = p;
 406         vp = p * view;
 407 }
 408
 409 void BlendedSprite::SetView(const glm::mat4 &v) noexcept {
 410         view = v;
 411         vp = projection * v;
 412 }
 413
 414 void BlendedSprite::SetVP(const glm::mat4 &v, const glm::mat4 &p) noexcept {
 415         projection = p;
 416         view = v;
 417         vp = p * v;
 418 }
 419
 420 void BlendedSprite::SetMVP(const glm::mat4 &m, const glm::mat4 &v, const glm::mat4 &p) noexcept {
 421         SetVP(v, p);
 422         SetM(m);
 423 }
 424
 425 void BlendedSprite::SetTexture(Texture &tex) noexcept {
 426         glActiveTexture(GL_TEXTURE0);
 427         tex.Bind();
 428         glUniform1i(sampler_handle, 0);
 429 }
 430
 431 }