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         GLContext::EnableDepthTest();
 219         GLContext::EnableBackfaceCulling();
 220         program.Use();
 221
 222         glUniform3f(light_direction_handle, light_direction.x, light_direction.y, light_direction.z);
 223         glUniform3f(light_color_handle, light_color.x, light_color.y, light_color.z);
 224 }
 225
 226 void DirectionalLighting::SetM(const glm::mat4 &m) noexcept {
 227         glm::mat4 mv(view * m);
 228         glm::mat4 mvp(vp * m);
 229         glUniformMatrix4fv(m_handle, 1, GL_FALSE, &m[0][0]);
 230         glUniformMatrix4fv(mv_handle, 1, GL_FALSE, &mv[0][0]);
 231         glUniformMatrix4fv(mvp_handle, 1, GL_FALSE, &mvp[0][0]);
 232 }
 233
 234 void DirectionalLighting::SetLightDirection(const glm::vec3 &dir) noexcept {
 235         light_direction = -dir;
 236         glUniform3f(light_direction_handle, light_direction.x, light_direction.y, light_direction.z);
 237 }
 238
 239 void DirectionalLighting::SetFogDensity(float f) noexcept {
 240         fog_density = f;
 241         glUniform1f(fog_density_handle, fog_density);
 242 }
 243
 244 void DirectionalLighting::SetProjection(const glm::mat4 &p) noexcept {
 245         projection = p;
 246         vp = p * view;
 247 }
 248
 249 void DirectionalLighting::SetView(const glm::mat4 &v) noexcept {
 250         view = v;
 251         vp = projection * v;
 252 }
 253
 254 void DirectionalLighting::SetVP(const glm::mat4 &v, const glm::mat4 &p) noexcept {
 255         projection = p;
 256         view = v;
 257         vp = p * v;
 258 }
 259
 260 void DirectionalLighting::SetMVP(const glm::mat4 &m, const glm::mat4 &v, const glm::mat4 &p) noexcept {
 261         SetVP(v, p);
 262         SetM(m);
 263 }
 264
 265
 266 BlockLighting::BlockLighting()
 267 : program()
 268 , vp(1.0f)
 269 , mv_handle(0)
 270 , mvp_handle(0)
 271 , fog_density_handle(0) {
 272         program.LoadShader(
 273                 GL_VERTEX_SHADER,
 274                 "#version 330 core\n"
 275                 "layout(location = 0) in vec3 vtx_position;\n"
 276                 "layout(location = 1) in vec3 vtx_color;\n"
 277                 "layout(location = 2) in float vtx_light;\n"
 278                 "uniform mat4 MV;\n"
 279                 "uniform mat4 MVP;\n"
 280                 "out vec3 frag_color;\n"
 281                 "out vec3 vtx_viewspace;\n"
 282                 "out float frag_light;\n"
 283                 "void main() {\n"
 284                         "gl_Position = MVP * vec4(vtx_position, 1);\n"
 285                         "frag_color = vtx_color;\n"
 286                         "vtx_viewspace = (MV * vec4(vtx_position, 1)).xyz;\n"
 287                         "frag_light = vtx_light;\n"
 288                 "}\n"
 289         );
 290         program.LoadShader(
 291                 GL_FRAGMENT_SHADER,
 292                 "#version 330 core\n"
 293                 "in vec3 frag_color;\n"
 294                 "in vec3 vtx_viewspace;\n"
 295                 "in float frag_light;\n"
 296                 "uniform float fog_density;\n"
 297                 "out vec3 color;\n"
 298                 "void main() {\n"
 299                         "vec3 ambient = vec3(0.1, 0.1, 0.1) * frag_color;\n"
 300                         "float light_power = clamp(pow(0.8, 15 - frag_light), 0, 1);\n"
 301                         "vec3 fog_color = vec3(0, 0, 0);\n"
 302                         "float e = 2.718281828;\n"
 303                         //"vec3 reflect_color = ambient + frag_color * light_power;\n"
 304                         "vec3 reflect_color = frag_color * light_power;\n"
 305                         "float value = pow(e, -pow(fog_density * length(vtx_viewspace), 5));"
 306                         "color = mix(fog_color, reflect_color, value);\n"
 307                 "}\n"
 308         );
 309         program.Link();
 310         if (!program.Linked()) {
 311                 program.Log(std::cerr);
 312                 throw std::runtime_error("link program");
 313         }
 314
 315         mv_handle = program.UniformLocation("MV");
 316         mvp_handle = program.UniformLocation("MVP");
 317         fog_density_handle = program.UniformLocation("fog_density");
 318 }
 319
 320
 321 void BlockLighting::Activate() noexcept {
 322         GLContext::EnableDepthTest();
 323         GLContext::EnableBackfaceCulling();
 324         GLContext::DisableAlphaBlending();
 325         program.Use();
 326 }
 327
 328 void BlockLighting::SetM(const glm::mat4 &m) noexcept {
 329         glm::mat4 mv(view * m);
 330         glm::mat4 mvp(vp * m);
 331         glUniformMatrix4fv(mv_handle, 1, GL_FALSE, &mv[0][0]);
 332         glUniformMatrix4fv(mvp_handle, 1, GL_FALSE, &mvp[0][0]);
 333 }
 334
 335 void BlockLighting::SetFogDensity(float f) noexcept {
 336         fog_density = f;
 337         glUniform1f(fog_density_handle, fog_density);
 338 }
 339
 340 void BlockLighting::SetProjection(const glm::mat4 &p) noexcept {
 341         projection = p;
 342         vp = p * view;
 343 }
 344
 345 void BlockLighting::SetView(const glm::mat4 &v) noexcept {
 346         view = v;
 347         vp = projection * v;
 348 }
 349
 350 void BlockLighting::SetVP(const glm::mat4 &v, const glm::mat4 &p) noexcept {
 351         projection = p;
 352         view = v;
 353         vp = p * v;
 354 }
 355
 356 void BlockLighting::SetMVP(const glm::mat4 &m, const glm::mat4 &v, const glm::mat4 &p) noexcept {
 357         SetVP(v, p);
 358         SetM(m);
 359 }
 360
 361
 362 BlendedSprite::BlendedSprite()
 363 : program()
 364 , vp(1.0f)
 365 , mvp_handle(0)
 366 , sampler_handle(0) {
 367         program.LoadShader(
 368                 GL_VERTEX_SHADER,
 369                 "#version 330 core\n"
 370                 "layout(location = 0) in vec3 vtx_position;\n"
 371                 "layout(location = 1) in vec2 vtx_tex_uv;\n"
 372                 "uniform mat4 MVP;\n"
 373                 "out vec2 frag_tex_uv;\n"
 374                 "void main() {\n"
 375                         "gl_Position = MVP * vec4(vtx_position, 1);\n"
 376                         "frag_tex_uv = vtx_tex_uv;\n"
 377                 "}\n"
 378         );
 379         program.LoadShader(
 380                 GL_FRAGMENT_SHADER,
 381                 "#version 330 core\n"
 382                 "in vec2 frag_tex_uv;\n"
 383                 "uniform sampler2D tex_sampler;\n"
 384                 "out vec4 color;\n"
 385                 "void main() {\n"
 386                         "color = texture(tex_sampler, frag_tex_uv);\n"
 387                 "}\n"
 388         );
 389         program.Link();
 390         if (!program.Linked()) {
 391                 program.Log(std::cerr);
 392                 throw std::runtime_error("link program");
 393         }
 394
 395         mvp_handle = program.UniformLocation("MVP");
 396         sampler_handle = program.UniformLocation("tex_sampler");
 397 }
 398
 399
 400 void BlendedSprite::Activate() noexcept {
 401         GLContext::EnableAlphaBlending();
 402         program.Use();
 403 }
 404
 405 void BlendedSprite::SetM(const glm::mat4 &m) noexcept {
 406         glm::mat4 mvp(vp * m);
 407         glUniformMatrix4fv(mvp_handle, 1, GL_FALSE, &mvp[0][0]);
 408 }
 409
 410 void BlendedSprite::SetProjection(const glm::mat4 &p) noexcept {
 411         projection = p;
 412         vp = p * view;
 413 }
 414
 415 void BlendedSprite::SetView(const glm::mat4 &v) noexcept {
 416         view = v;
 417         vp = projection * v;
 418 }
 419
 420 void BlendedSprite::SetVP(const glm::mat4 &v, const glm::mat4 &p) noexcept {
 421         projection = p;
 422         view = v;
 423         vp = p * v;
 424 }
 425
 426 void BlendedSprite::SetMVP(const glm::mat4 &m, const glm::mat4 &v, const glm::mat4 &p) noexcept {
 427         SetVP(v, p);
 428         SetM(m);
 429 }
 430
 431 void BlendedSprite::SetTexture(Texture &tex) noexcept {
 432         glActiveTexture(GL_TEXTURE0);
 433         tex.Bind();
 434         glUniform1i(sampler_handle, 0);
 435 }
 436
 437 }