src/shader.c

   1 #define STB_INCLUDE_IMPLEMENTATION
   2 #define STB_INCLUDE_LINE_GLSL
   3 #include "../dep/stb/stb_include.h"
   4 #define VG_TOOLS
   5 #include "vg/vg.h"
   6
   7 struct uniform
   8 {
   9    char name[30];
  10    char type[20];
  11
  12    int array;
  13 }
  14 uniform_buffer[100];
  15 static int uniform_count;
  16
  17 static int compile_subshader( FILE *header, char *name )
  18 {
  19    char error[256];
  20    char *full = stb_include_file( name, "", ".", error );
  21
  22    if( !full )
  23    {
  24       fprintf( stderr, "stb_include_file error:\n%s\n", error );
  25       return 0;
  26    }
  27    else
  28    {
  29       /* VG */
  30
  31       fprintf( header, "{\n"
  32          ".orig_file = \"../../shaders/%s\",\n"
  33          ".static_src = \n", name );
  34
  35       char *cur = full, *start = full;
  36       while( 1 )
  37       {
  38          char c = *cur;
  39          if( c == '\n' || c == '\0' )
  40          {
  41             *cur = '\0';
  42             fputs( "\"", header );
  43             fputs( start, header );
  44
  45             if( !strncmp(start,"uniform",7) )
  46             {
  47                start += 8;
  48                struct uniform *uf = &uniform_buffer[ uniform_count ++ ];
  49                uf->array = 0;
  50                for( int i=0;; i++ )
  51                {
  52                   if( start[i] == '\0' )
  53                      break;
  54
  55                   if( start[i] == ';' )
  56                   {
  57                      start[i] = '\0';
  58                      strncpy( uf->name, start, sizeof(uf->name) );
  59                   }
  60
  61                   if( start[i] == '[' )
  62                   {
  63                      start[i] = '\0';
  64                      strncpy( uf->name, start, sizeof(uf->name) );
  65                      uf->array = 1;
  66                   }
  67
  68                   if( start[i] == ' ' )
  69                   {
  70                      start[i] = '\0';
  71                      strncpy( uf->type, start, sizeof(uf->type) );
  72                      start = start+i+1;
  73                      i=0;
  74                   }
  75                }
  76             }
  77
  78             if( c == '\0' )
  79             {
  80                fputs( "\"", header );
  81                break;
  82             }
  83
  84             fputs( "\\n\"\n", header );
  85             start = cur+1;
  86          }
  87          cur ++;
  88       }
  89
  90       fputs( "},", header );
  91    }
  92
  93    free( full );
  94    return 1;
  95 }
  96
  97 int main( int argc, char *argv[] )
  98 {
  99    if( argc < 2 || (argc-1)%3 != 0 )
 100    {
 101       fprintf( stderr, "invalid\n" );
 102       return 0;
 103    }
 104
 105    char path[260];
 106    int shader_count = (argc-1)/3;
 107    for( int i=0; i<shader_count; i++ )
 108    {
 109       char **args = &argv[1+i*3];
 110       strcpy( path, args[0] );
 111       strcat( path, ".h" );
 112
 113       printf( "Compiling shader called '%s'\n", args[0] );
 114
 115       FILE *header = fopen( path, "w" );
 116       if( !header )
 117       {
 118          fprintf(stderr, "Could not open '%s'\n", path );
 119          continue;
 120       }
 121
 122       fprintf( header, "#ifndef SHADER_%s_H\n"
 123                        "#define SHADER_%s_H\n", args[0], args[0] );
 124       fprintf( header, "static void shader_%s_link(void);\n", args[0] );
 125       fprintf( header, "static void shader_%s_register(void);\n", args[0] );
 126       fprintf( header, "static struct vg_shader _shader_%s = {\n"
 127                        "   .name = \"%s\",\n"
 128                        "   .link = shader_%s_link,\n"
 129                        "   .vs = \n", args[0], args[0], args[0] );
 130
 131       uniform_count = 0;
 132       if( !compile_subshader(header,args[1]) )
 133       {
 134          fclose( header );
 135          continue;
 136       }
 137
 138       fprintf( header, "\n   .fs = \n" );
 139       if( !compile_subshader(header,args[2]) )
 140       {
 141          fclose( header );
 142          continue;
 143       }
 144
 145       fprintf( header, "\n};\n\n" );
 146
 147       for( int i=0; i<uniform_count; i++ )
 148       {
 149          struct uniform *uf = &uniform_buffer[i];
 150          fprintf( header, "static GLuint _uniform_%s_%s;\n", args[0], uf->name);
 151       }
 152
 153       for( int i=0; i<uniform_count; i++ )
 154       {
 155          struct uniform *uf = &uniform_buffer[i];
 156          if( uf->array ) continue;
 157
 158          if( !strcmp(uf->type,"vec2") )
 159          {
 160             fprintf( header, "static void shader_%s_%s(v2f v){\n"
 161                              "   glUniform2fv( _uniform_%s_%s, 1, v );\n"
 162                              "}\n", args[0], uf->name, args[0], uf->name );
 163          }
 164          if( !strcmp(uf->type,"vec3") )
 165          {
 166             fprintf( header, "static void shader_%s_%s(v3f v){\n"
 167                              "   glUniform3fv( _uniform_%s_%s, 1, v );\n"
 168                              "}\n", args[0], uf->name, args[0], uf->name );
 169          }
 170          if( !strcmp(uf->type,"vec4") )
 171          {
 172             fprintf( header, "static void shader_%s_%s(v4f v){\n"
 173                              "   glUniform4fv( _uniform_%s_%s, 1, v );\n"
 174                              "}\n", args[0], uf->name, args[0], uf->name );
 175          }
 176          if( !strcmp(uf->type,"sampler2D") )
 177          {
 178             fprintf( header, "static void shader_%s_%s(int i){\n"
 179                              "   glUniform1i( _uniform_%s_%s, i );\n"
 180                              "}\n", args[0], uf->name, args[0], uf->name );
 181          }
 182          if( !strcmp(uf->type,"float") )
 183          {
 184             fprintf( header, "static void shader_%s_%s(float f){\n"
 185                              "   glUniform1f( _uniform_%s_%s, f );\n"
 186                              "}\n", args[0], uf->name, args[0], uf->name );
 187          }
 188          if( !strcmp(uf->type,"mat4x3") )
 189          {
 190             fprintf( header,
 191                "static void shader_%s_%s(m4x3f m){\n"
 192                "   glUniformMatrix4x3fv"
 193                      "( _uniform_%s_%s, 1, GL_FALSE, (float *)m );\n"
 194                "}\n", args[0], uf->name, args[0], uf->name );
 195          }
 196          if( !strcmp(uf->type,"mat3") )
 197          {
 198             fprintf( header,
 199                "static void shader_%s_%s(m3x3f m){\n"
 200                "   glUniformMatrix3fv"
 201                      "( _uniform_%s_%s, 1, GL_FALSE, (float *)m );\n"
 202                "}\n", args[0], uf->name, args[0], uf->name );
 203          }
 204          if( !strcmp(uf->type,"mat4") )
 205          {
 206             fprintf( header,
 207                "static void shader_%s_%s(m4x4f m){\n"
 208                "   glUniformMatrix4fv"
 209                      "( _uniform_%s_%s, 1, GL_FALSE, (float *)m );\n"
 210                "}\n", args[0], uf->name, args[0], uf->name );
 211          }
 212       }
 213
 214       fprintf( header,
 215             "static void shader_%s_register(void){\n"
 216             "   vg_shader_register( &_shader_%s );\n"
 217             "}\n",
 218                args[0],args[0] );
 219
 220       fprintf( header,
 221             "static void shader_%s_use(void){ glUseProgram(_shader_%s.id); }\n",
 222                args[0], args[0] );
 223
 224       fprintf( header,
 225             "static void shader_%s_link(void){\n",
 226                args[0] );
 227
 228       for( int i=0; i<uniform_count; i++ )
 229       {
 230          struct uniform *uf = &uniform_buffer[i];
 231          fprintf( header,
 232             "   _uniform_%s_%s = "
 233                "glGetUniformLocation( _shader_%s.id, \"%s\" );\n",
 234             args[0], uf->name,
 235             args[0], uf->name );
 236       }
 237
 238       fprintf( header, "}\n" );
 239       fprintf( header, "#endif /* SHADER_%s_H */\n", args[0] );
 240       fclose( header );
 241    }
 242 }