glutils.d

   1 /* DooM2D: Midnight on the Firing Line
   2  * coded by Ketmar // Invisible Vector <ketmar@ketmar.no-ip.org>
   3  * Understanding is not required. Only obedience.
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, either version 3 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  17  */
  18 module glutils is aliced;
  19 private:
  20 import iv.glbinds;
  21 import arsd.color;
  22 import arsd.png;
  23
  24 import wadarc;
  25
  26
  27 // ////////////////////////////////////////////////////////////////////////// //
  28 __gshared bool glutilsShowShaderWarnings = false; // shut up!
  29
  30 /*
  31 __gshared GLuint glLastUsedTexture = 0;
  32
  33 public void useTexture (GLuint tid) {
  34   pragma(inline, true);
  35   if (glLastUsedTexture != tid) {
  36     glLastUsedTexture = tid;
  37     glBindTexture(GL_TEXTURE_2D, tid);
  38   }
  39 }
  40
  41 public void useTexture (Texture tex) { pragma(inline, true); useTexture(tex !is null ? tex.tid : 0); }
  42 */
  43
  44
  45 public TrueColorImage loadPngFile (string fname) {
  46   auto fl = openFile(fname);
  47   auto sz = fl.size;
  48   if (sz < 4 || sz > 32*1024*1024) throw new Exception("invalid png file size: '"~fname~"'");
  49   if (sz == 0) return null;
  50   auto res = new ubyte[](cast(uint)sz);
  51   if (fl.rawRead(res[]).length != res.length) throw new Exception("error reading png file '"~fname~"'");
  52   return imageFromPng(readPng(res)).getAsTrueColorImage;
  53 }
  54
  55
  56 // ////////////////////////////////////////////////////////////////////////// //
  57 class OpenGLObject {
  58   abstract @property uint id () const pure nothrow @nogc;
  59
  60   final void activate () nothrow @nogc {
  61     if (gloSP >= gloStack.length) assert(0, "glo stack overflow");
  62     gloStack.ptr[gloSP++] = this;
  63     activateObj();
  64   }
  65
  66   final void deactivate () nothrow @nogc {
  67     foreach_reverse (usize idx; 0..gloStack.length) {
  68       if (gloStack.ptr[idx] is this) {
  69         // find previous object of this type
  70         foreach_reverse (usize pidx; 0..idx) {
  71           if (typeid(gloStack.ptr[pidx]) is typeid(gloStack.ptr[idx])) {
  72             gloStack.ptr[pidx].activateObj();
  73             removeFromStack(pidx);
  74             return;
  75           }
  76         }
  77         deactivateObj();
  78         removeFromStack(idx);
  79         return;
  80       }
  81     }
  82     assert(0, "trying to deactivate inactive object");
  83   }
  84
  85 protected:
  86   abstract void activateObj () nothrow @nogc;
  87   abstract void deactivateObj () nothrow @nogc;
  88 }
  89
  90
  91 __gshared OpenGLObject[1024] gloStack;
  92 __gshared uint gloSP = 0;
  93
  94
  95 public void gloStackClear () nothrow @nogc {
  96   glBindTexture(GL_TEXTURE_2D, 0);
  97   //glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
  98   glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
  99   glUseProgram(0);
 100 }
 101
 102
 103 void removeFromStack (usize idx) nothrow @nogc {
 104   if (idx >= gloSP) return;
 105   if (idx != gloSP-1) {
 106     import core.stdc.string : memmove;
 107     memmove(gloStack.ptr+idx, gloStack.ptr+idx+1, (gloSP-idx-1)*gloStack[0].sizeof);
 108   }
 109   --gloSP;
 110 }
 111
 112
 113 // ////////////////////////////////////////////////////////////////////////// //
 114 public final class Texture : OpenGLObject {
 115   GLuint tid;
 116   int width, height;
 117
 118   override @property uint id () const pure nothrow @nogc => tid;
 119
 120   // default: repeat, linear
 121   enum Option : int {
 122     Repeat,
 123     Clamp,
 124     ClampBorder,
 125     Linear,
 126     Nearest,
 127     UByte,
 128     Float, // create floating point texture
 129     Depth, // FBO: attach depth buffer
 130   }
 131
 132   this (string fname, in Option[] opts...) { loadPng(fname, opts); }
 133   this (int w, int h, in Option[] opts...) { createIntr(w, h, null, opts); }
 134   this (TrueColorImage aimg, Option[] opts...) { createIntr(aimg.width, aimg.height, aimg, opts); }
 135   ~this () { clear(); }
 136
 137
 138   void clear () {
 139     if (tid) {
 140       //useTexture(tid);
 141       glBindTexture(GL_TEXTURE_2D, tid);
 142       glDeleteTextures(1, &tid);
 143       //useTexture(0);
 144       glBindTexture(GL_TEXTURE_2D, 0);
 145       tid = 0;
 146       width = 0;
 147       height = 0;
 148     }
 149   }
 150
 151   private static void processOpt (GLuint* wrapOpt, GLuint* filterOpt, GLuint* ttype, in Option[] opts...) {
 152     foreach (immutable opt; opts) {
 153       switch (opt) with (Option) {
 154         case Repeat: *wrapOpt = GL_REPEAT; break;
 155         case Clamp: *wrapOpt = GL_CLAMP_TO_EDGE; break;
 156         case ClampBorder: *wrapOpt = GL_CLAMP_TO_BORDER; break;
 157         case Linear: *filterOpt = GL_LINEAR; break;
 158         case Nearest: *filterOpt = GL_NEAREST; break;
 159         case UByte: *ttype = GL_UNSIGNED_BYTE; break;
 160         case Float: *ttype = GL_FLOAT; break;
 161         default:
 162       }
 163     }
 164   }
 165
 166   void createIntr (int w, int h, TrueColorImage img, in Option[] opts...) {
 167     import core.stdc.stdlib : malloc, free;
 168     assert(w > 0);
 169     assert(h > 0);
 170     clear();
 171
 172     GLuint wrapOpt = GL_REPEAT;
 173     GLuint filterOpt = GL_LINEAR;
 174     GLuint ttype = GL_UNSIGNED_BYTE;
 175     processOpt(&wrapOpt, &filterOpt, &ttype, opts);
 176
 177     glGenTextures(1, &tid);
 178     //useTexture(tid);
 179     glBindTexture(GL_TEXTURE_2D, tid);
 180     scope(exit) glBindTexture(GL_TEXTURE_2D, 0);
 181     glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapOpt);
 182     glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapOpt);
 183     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filterOpt);
 184     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filterOpt);
 185     //glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
 186     //glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
 187     GLfloat[4] bclr = 0.0;
 188     glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR, bclr.ptr);
 189     if (img !is null && img.width == w && img.height == h) {
 190       // create straight from image
 191       glTexImage2D(GL_TEXTURE_2D, 0, (ttype == GL_FLOAT ? GL_RGBA16F : GL_RGBA), w, h, 0, GL_RGBA, GL_UNSIGNED_BYTE, img.imageData.bytes.ptr);
 192     } else {
 193       // create empty texture
 194       ubyte* ptr = null;
 195       scope(exit) if (ptr !is null) free(ptr);
 196       {
 197         import core.stdc.string : memset;
 198         ptr = cast(ubyte*)malloc(w*h*4);
 199         if (ptr !is null) memset(ptr, 0, w*h*4);
 200       }
 201       glTexImage2D(GL_TEXTURE_2D, 0, (ttype == GL_FLOAT ? GL_RGBA16F : GL_RGBA), w, h, 0, GL_RGBA, GL_UNSIGNED_BYTE, ptr);
 202       if (img !is null && img.width > 0 && img.height > 0) {
 203         // setup from image
 204         //TODO: dunno if it's ok to use images bigger than texture here
 205         glTexSubImage2D(GL_TEXTURE_2D, 0,  0, 0, img.width, img.height, GL_RGBA, GL_UNSIGNED_BYTE, img.imageData.bytes.ptr);
 206         // the following is ok too
 207         //glBindTexture(GL_TEXTURE_2D, 0);
 208         //glTextureSubImage2D(tid, 0,  0, 0, img.width, img.height, GL_RGBA, GL_UNSIGNED_BYTE, img.imageData.bytes.ptr);
 209       }
 210     }
 211     width = w;
 212     height = h;
 213   }
 214
 215   void setFromImage (TrueColorImage img, int x=0, int y=0) {
 216     if (img is null || !tid || img.height < 1 || img.width < 1) return;
 217     if (x >= width || y >= height) return;
 218     if (x+img.width <= 0 || y+img.height <= 0) return; //TODO: overflow
 219     if (x >= 0 && y >= 0 && x+img.width <= width && y+img.height <= height) {
 220       // easy case, just copy it
 221       glTextureSubImage2D(tid, 0, x, y, img.width, img.height, GL_RGBA, GL_UNSIGNED_BYTE, img.imageData.bytes.ptr);
 222     } else {
 223       import core.stdc.stdlib : malloc, free;
 224       import core.stdc.string : memset, memcpy;
 225       // hard case, have to build the temp region
 226       uint* src = cast(uint*)img.imageData.bytes.ptr;
 227       // calc x skip and effective width
 228       int rwdt = img.width;
 229       if (x < 0) {
 230         rwdt += x;
 231         src -= x; // as `x` is negative here
 232         x = 0;
 233       }
 234       if (x+rwdt > width) rwdt = width-x;
 235       // calc y skip and effective height
 236       int rhgt = img.height;
 237       if (y < 0) {
 238         rhgt += y;
 239         src -= y*img.width; // as `y` is negative here
 240         y = 0;
 241       }
 242       if (y+rhgt > height) rhgt = height-y;
 243       assert(rwdt > 0 && rhgt > 0);
 244       uint* ptr = null;
 245       scope(exit) if (ptr !is null) free(ptr);
 246       ptr = cast(uint*)malloc(rwdt*rhgt*4);
 247       if (ptr is null) assert(0, "out of memory in `Texture.setFromImage()`");
 248       // now copy
 249       auto d = ptr;
 250       foreach (immutable _; 0..rhgt) {
 251         memcpy(d, src, rwdt*4);
 252         src += img.width;
 253         d += rwdt;
 254       }
 255       glTextureSubImage2D(tid, 0, x, y, rwdt, rhgt, GL_RGBA, GL_UNSIGNED_BYTE, ptr);
 256     }
 257   }
 258
 259   void loadPng (string fname, in Option[] opts...) {
 260     scope(failure) clear;
 261     auto img = loadPngFile(fname);
 262     createIntr(img.width, img.height, img, opts);
 263   }
 264
 265 protected:
 266   override void activateObj () nothrow @nogc { /*if (tid)*/ glBindTexture(GL_TEXTURE_2D, tid); }
 267   override void deactivateObj () nothrow @nogc { /*if (tid)*/ glBindTexture(GL_TEXTURE_2D, 0); }
 268 }
 269
 270
 271 // ////////////////////////////////////////////////////////////////////////// //
 272 /+
 273 public final class TextureCube : OpenGLObject {
 274   GLuint tid;
 275   int width, height;
 276
 277   override @property uint id () const pure nothrow @nogc => tid;
 278
 279   this (string fname, in Texture.Option[] opts...) { loadPng(fname, opts); }
 280   this (int w, int h, in Texture.Option[] opts...) { createIntr(w, h, opts); }
 281   ~this () { clear(); }
 282
 283
 284   void clear () {
 285     if (tid) {
 286       glBindTexture(GL_TEXTURE_CUBE_MAP, tid);
 287       glDeleteTextures(1, &tid);
 288       glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
 289       tid = 0;
 290       width = 0;
 291       height = 0;
 292     }
 293   }
 294
 295   void createIntr (int w, int h, in Texture.Option[] opts...) {
 296     import core.stdc.stdlib : malloc, free;
 297     assert(w > 0);
 298     assert(h > 0);
 299
 300     GLuint wrapOpt = GL_CLAMP_TO_EDGE;
 301     GLuint filterOpt = GL_LINEAR;
 302     GLuint ttype = GL_FLOAT;
 303     Texture.processOpt(&wrapOpt, &filterOpt, &ttype, opts);
 304
 305     glGenTextures(1, &tid);
 306     glBindTexture(GL_TEXTURE_CUBE_MAP, tid);
 307     scope(exit) glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
 308     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, wrapOpt);
 309     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, wrapOpt);
 310     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, wrapOpt);
 311     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, filterOpt);
 312     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, filterOpt);
 313     GLfloat[4] bclr = 0.0;
 314     glTexParameterfv(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_BORDER_COLOR, bclr.ptr);
 315
 316     ubyte* ptr = null;
 317     scope(exit) if (ptr !is null) free(ptr);
 318     {
 319       import core.stdc.string : memset;
 320       ptr = cast(ubyte*)malloc(w*h*4*4);
 321       memset(ptr, 0, w*h*4);
 322     }
 323     foreach (int idx; 0..6) {
 324       glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X+idx, 0, (ttype == GL_FLOAT ? GL_RGBA16F : GL_RGBA), w, h, 0, GL_BGRA, GL_FLOAT, ptr);
 325     }
 326     width = w;
 327     height = h;
 328   }
 329
 330   void loadPng (string fname, in Texture.Option[] opts...) {
 331     clear();
 332     TrueColorImage[6] img;
 333     foreach (int idx; 0..6) {
 334       import std.string : format;
 335       img[idx] = loadPngFile(fname.format(idx));
 336       if (idx > 0) {
 337         if (img[idx].width != img[idx-1].width || img[idx].height != img[idx-1].height) {
 338           assert(0, "cubemap fucked: "~fname);
 339         }
 340       }
 341     }
 342     createIntr(img[0].width, img[0].height, opts);
 343     glBindTexture(GL_TEXTURE_CUBE_MAP, tid);
 344     scope(exit) glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
 345     foreach (int idx; 0..6) {
 346       glTexSubImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X+idx, 0,  0, 0, img[idx].width, img[idx].height, GL_RGBA, GL_UNSIGNED_BYTE, img[idx].imageData.bytes.ptr);
 347     }
 348   }
 349
 350   void activate () { if (tid) glBindTexture(GL_TEXTURE_CUBE_MAP, tid); }
 351   void deactivate () { if (tid) glBindTexture(GL_TEXTURE_CUBE_MAP, 0); }
 352 }
 353 +/
 354
 355
 356 // ////////////////////////////////////////////////////////////////////////// //
 357 public final class FBO : OpenGLObject {
 358   int width;
 359   int height;
 360   GLuint fbo;
 361   Texture tex;
 362   Texture texdepth;
 363   //Texture.Option[] xopts;
 364
 365   override @property uint id () const pure nothrow @nogc => fbo;
 366
 367   this (Texture atex) { createWithTexture(atex); }
 368
 369   this (int wdt, int hgt, Texture.Option[] opts...) {
 370     //xopts = opts.dup;
 371     createWithTexture(new Texture(wdt, hgt, opts), opts);
 372   }
 373
 374   ~this () {
 375     //FIXME: this may be wrong, as texture may be already destroyed (and it's wrong too); we need refcount for textures
 376     glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, 0, 0);
 377     glDeleteFramebuffersEXT(1, &fbo);
 378     fbo = 0;
 379   }
 380
 381   void clear () {
 382     if (fbo) {
 383       // detach texture
 384       glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, 0, 0);
 385       glDeleteFramebuffersEXT(1, &fbo);
 386       glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, 0, 0);
 387       glDeleteFramebuffersEXT(1, &fbo);
 388       fbo = 0;
 389     }
 390     if (tex !is null) tex.clear();
 391     tex = null;
 392     if (texdepth !is null) texdepth.clear();
 393     texdepth = null;
 394   }
 395
 396 protected:
 397   override void activateObj () nothrow @nogc { /*if (fbo)*/ glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo); }
 398   override void deactivateObj () nothrow @nogc { glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0); }
 399
 400   // this will deactivate current FBO!
 401   /+
 402   void replaceTexture (Texture ntex) {
 403     if (tex !is null) {
 404       if (ntex !is null && ntex.tid == tex.tid) return;
 405     } else {
 406       if (ntex is null) return;
 407     }
 408     glGenFramebuffersEXT(1, &fbo);
 409     glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo);
 410     scope(exit) glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
 411     // detach texture
 412     glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, 0, 0);
 413     glDeleteFramebuffersEXT(1, &fbo);
 414     fbo = 0;
 415     tex = ntex;
 416     // attach texture
 417     if (tex !is null) {
 418       glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, tex.tid, 0);
 419       {
 420         GLenum status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
 421         if (status != GL_FRAMEBUFFER_COMPLETE_EXT) assert(0, "framebuffer fucked!");
 422       }
 423     }
 424   }
 425   +/
 426
 427 private:
 428   void createWithTexture (Texture atex, Texture.Option[] opts...) {
 429     assert(atex !is null && atex.tid);
 430
 431     tex = atex;
 432     glGenFramebuffersEXT(1, &fbo);
 433     glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo);
 434     scope(exit) glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
 435     // attach 2D texture to this FBO
 436     glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, tex.tid, 0);
 437     // GL_COLOR_ATTACHMENT0_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_STENCIL_ATTACHMENT_EXT
 438
 439     void createDepth () {
 440       uint fboDepthId;
 441       glGenRenderbuffersEXT(1, &fboDepthId);
 442       glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, fboDepthId);
 443       glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT/*24*/, atex.width, atex.height);
 444       // attach depth buffer to FBO
 445       glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, fboDepthId);
 446       // kill it (we don't need it anymore)
 447       glDeleteRenderbuffersEXT(1, &fboDepthId);
 448     }
 449
 450     /*
 451     foreach (Texture.Option opt; opts) {
 452       if (opt == Texture.Option.Depth) {
 453         createDepth();
 454         break;
 455       }
 456     }
 457     */
 458     //createDepth();
 459
 460     {
 461       GLenum status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
 462       if (status != GL_FRAMEBUFFER_COMPLETE_EXT) assert(0, "framebuffer fucked!");
 463     }
 464     glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
 465
 466     width = tex.width;
 467     height = tex.height;
 468   }
 469 }
 470
 471
 472 // ////////////////////////////////////////////////////////////////////////// //
 473 public struct SVec2I { int x, y; }
 474 public struct SVec3I { int x, y, z; alias r = x; alias g = y; alias b = z; }
 475 public struct SVec4I { int x, y, z, w; alias r = x; alias g = y; alias b = z; alias a = w; }
 476
 477 public struct SVec2F { float x, y; }
 478 public struct SVec3F { float x, y, z; alias r = x; alias g = y; alias b = z; }
 479 public struct SVec4F { float x, y, z, w; alias r = x; alias g = y; alias b = z; alias a = w; }
 480
 481
 482 public final class Shader : OpenGLObject {
 483   string shaderName;
 484   GLuint prg = 0;
 485   GLint[string] vars;
 486
 487   override @property uint id () const pure nothrow @nogc => prg;
 488
 489   this (string ashaderName, const(char)[] src) {
 490     shaderName = ashaderName;
 491     if (src.length > int.max) {
 492       import core.stdc.stdio : printf;
 493       printf("shader '%.*s' code too long!", cast(uint)ashaderName.length, ashaderName.ptr);
 494       assert(0);
 495     }
 496     auto shaderId = glCreateShader(GL_FRAGMENT_SHADER);
 497     auto sptr = src.ptr;
 498     GLint slen = cast(int)src.length;
 499     glShaderSource(shaderId, 1, &sptr, &slen);
 500     glCompileShader(shaderId);
 501     GLint success = 0;
 502     glGetShaderiv(shaderId, GL_COMPILE_STATUS, &success);
 503     if (!success || glutilsShowShaderWarnings) {
 504       import core.stdc.stdio : printf;
 505       import core.stdc.stdlib : malloc, free;
 506       GLint logSize = 0;
 507       glGetShaderiv(shaderId, GL_INFO_LOG_LENGTH, &logSize);
 508       if (logSize > 0) {
 509         auto logStrZ = cast(GLchar*)malloc(logSize);
 510         glGetShaderInfoLog(shaderId, logSize, null, logStrZ);
 511         printf("shader '%.*s' compilation messages:\n%s\n", cast(uint)ashaderName.length, ashaderName.ptr, logStrZ);
 512         free(logStrZ);
 513       }
 514     }
 515     if (!success) assert(0);
 516     prg = glCreateProgram();
 517     glAttachShader(prg, shaderId);
 518     glLinkProgram(prg);
 519   }
 520
 521   GLint varId(NT) (NT vname) if (is(NT == char[]) || is(NT == const(char)[]) || is(NT == immutable(char)[])) {
 522     GLint id = -1;
 523     if (vname.length > 0 && vname.length <= 128) {
 524       if (auto vi = vname in vars) {
 525         id = *vi;
 526       } else {
 527         char[129] buf = void;
 528         buf[0..vname.length] = vname[];
 529         buf[vname.length] = 0;
 530         id = glGetUniformLocation(prg, buf.ptr);
 531         //{ import core.stdc.stdio; printf("[%.*s.%s]=%i\n", cast(uint)shaderName.length, shaderName.ptr, buf.ptr, id); }
 532         static if (is(NT == immutable(char)[])) {
 533           vars[vname.idup] = id;
 534         } else {
 535           vars[vname.idup] = id;
 536         }
 537         if (id < 0) {
 538           import core.stdc.stdio : printf;
 539           printf("shader '%.*s': unknown variable '%.*s'\n", cast(uint)shaderName.length, shaderName.ptr, cast(uint)vname.length, vname.ptr);
 540         }
 541       }
 542     }
 543     return id;
 544   }
 545
 546   // get unified var id
 547   GLint opIndex(NT) (NT vname) if (is(NT == char[]) || is(NT == const(char)[]) || is(NT == immutable(char)[])) {
 548     auto id = varId(vname);
 549     if (id < 0) {
 550       import core.stdc.stdio : printf;
 551       printf("shader '%.*s': unknown variable '%.*s'\n", cast(uint)shaderName.length, shaderName.ptr, cast(uint)vname.length, vname.ptr);
 552       assert(0);
 553     }
 554     return id;
 555   }
 556
 557   private import std.traits;
 558   void opIndexAssign(T, NT) (in auto ref T v, NT vname)
 559   if (((isIntegral!T && T.sizeof <= 4) || (isFloatingPoint!T && T.sizeof == float.sizeof) || isBoolean!T ||
 560        is(T : SVec2I) || is(T : SVec3I) || is(T : SVec4I) ||
 561        is(T : SVec2F) || is(T : SVec3F) || is(T : SVec4F)) &&
 562       (is(NT == char[]) || is(NT == const(char)[]) || is(NT == immutable(char)[])))
 563   {
 564     auto id = varId(vname);
 565     if (id < 0) return;
 566     //{ import core.stdc.stdio; printf("setting '%.*s' (%d)\n", cast(uint)vname.length, vname.ptr, id); }
 567          static if (isIntegral!T || isBoolean!T) glUniform1i(id, cast(int)v);
 568     else static if (isFloatingPoint!T) glUniform1f(id, cast(float)v);
 569     else static if (is(SVec2I : T)) glUniform2i(id, cast(int)v.x, cast(int)v.y);
 570     else static if (is(SVec3I : T)) glUniform3i(id, cast(int)v.x, cast(int)v.y, cast(int)v.z);
 571     else static if (is(SVec4I : T)) glUniform4i(id, cast(int)v.x, cast(int)v.y, cast(int)v.z, cast(int)v.w);
 572     else static if (is(SVec2F : T)) glUniform2f(id, cast(float)v.x, cast(float)v.y);
 573     else static if (is(SVec3F : T)) glUniform3f(id, cast(float)v.x, cast(float)v.y, cast(float)v.z);
 574     else static if (is(SVec4F : T)) glUniform4f(id, cast(float)v.x, cast(float)v.y, cast(float)v.z, cast(float)v.w);
 575     else static assert(0, "wtf?!");
 576   }
 577
 578 protected:
 579   override void activateObj () nothrow @nogc { /*if (prg)*/ glUseProgram(prg); }
 580   override void deactivateObj () nothrow @nogc { glUseProgram(0); }
 581 }
 582
 583
 584 // ////////////////////////////////////////////////////////////////////////// //
 585 //private import std.traits;
 586
 587 public:
 588 void exec(TO) (TO obj, scope void delegate () dg) if (is(typeof(() { obj.activate(); obj.deactivate(); }))) {
 589   obj.activate();
 590   scope(exit) obj.deactivate();
 591   dg();
 592 }
 593
 594 void exec(TO, TG) (TO obj, scope TG dg) if (is(typeof((TO obj) { dg(obj); })) && is(typeof(() { obj.activate(); obj.deactivate(); }))) {
 595   obj.activate();
 596   scope(exit) obj.deactivate();
 597   dg(obj);
 598 }
 599
 600
 601 // ////////////////////////////////////////////////////////////////////////// //
 602 void orthoCamera (int wdt, int hgt) {
 603   glMatrixMode(GL_PROJECTION); // for ortho camera
 604   glLoadIdentity();
 605   // left, right, bottom, top, near, far
 606   //glOrtho(0, wdt, 0, hgt, -1, 1); // bottom-to-top
 607   glOrtho(0, wdt, hgt, 0, -1, 1); // top-to-bottom
 608   glViewport(0, 0, wdt, hgt);
 609 }
 610 //glTranslatef(-cx, -cy, 0.0f);
 611
 612
 613 // origin is texture left top
 614 void drawAtXY (GLuint tid, int x, int y, int w, int h, bool mirrorX=false, bool mirrorY=false) {
 615   if (!tid || w < 1 || h < 1) return;
 616   w += x;
 617   h += y;
 618   if (mirrorX) { int tmp = x; x = w; w = tmp; }
 619   if (mirrorY) { int tmp = y; y = h; h = tmp; }
 620   glBindTexture(GL_TEXTURE_2D, tid);
 621   glBegin(GL_QUADS);
 622     glTexCoord2f(0.0f, 0.0f); glVertex2i(x, y); // top-left
 623     glTexCoord2f(1.0f, 0.0f); glVertex2i(w, y); // top-right
 624     glTexCoord2f(1.0f, 1.0f); glVertex2i(w, h); // bottom-right
 625     glTexCoord2f(0.0f, 1.0f); glVertex2i(x, h); // bottom-left
 626   glEnd();
 627 }
 628
 629
 630 // origin is texture center
 631 void drawAtXYC (Texture tex, int x, int y, bool mirrorX=false, bool mirrorY=false) {
 632   if (tex is null || !tex.tid) return;
 633   x -= tex.width/2;
 634   y -= tex.height/2;
 635   drawAtXY(tex.tid, x, y, tex.width, tex.height, mirrorX, mirrorY);
 636 }
 637
 638
 639 // origin is texture left top
 640 void drawAtXY (Texture tex, int x, int y, bool mirrorX=false, bool mirrorY=false) {
 641   if (tex is null || !tex.tid) return;
 642   drawAtXY(tex.tid, x, y, tex.width, tex.height, mirrorX, mirrorY);
 643 }