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