Merged branch 'dev_native' into lm_sla_supports_auto

Added igl library files

src/igl/copyleft/opengl2/render_to_tga.cpp

@@ -0,0 +1,87 @@
+// This file is part of libigl, a simple c++ geometry processing library.
+// 
+// Copyright (C) 2014 Alec Jacobson <alecjacobson@gmail.com>
+// 
+// This Source Code Form is subject to the terms of the Mozilla Public License 
+// v. 2.0. If a copy of the MPL was not distributed with this file, You can 
+// obtain one at http://mozilla.org/MPL/2.0/.
+#include "render_to_tga.h"
+#include "tga.h"
+
+#include "../../opengl2/gl.h"
+
+#include <cstdlib>
+
+IGL_INLINE bool igl::opengl::render_to_tga(
+  const std::string tga_file,
+  const int width,
+  const int height,
+  const bool alpha)
+{
+
+  size_t components = 3;
+  GLenum format = GL_BGR;
+  if(alpha)
+  {
+    format = GL_BGRA;
+    components = 4;
+  }
+  GLubyte * cmap = NULL;
+
+  // OpenGL by default tries to read data in multiples of 4, if our data is
+  // only RGB or BGR and the width is not divible by 4 then we need to alert
+  // opengl
+  if((width % 4) != 0 && 
+   (format == GL_RGB || 
+    format == GL_BGR))
+  {
+    glPixelStorei(GL_PACK_ALIGNMENT, 1);
+  }
+  GLubyte *pixels;
+  pixels = (unsigned char *) malloc (width * height * components);
+  glReadPixels(
+    0,
+    0,
+    width,
+    height,
+    format,
+    GL_UNSIGNED_BYTE,
+    pixels);
+
+  // set up generic image struct
+  gliGenericImage * genericImage;
+  genericImage = (gliGenericImage*) malloc(sizeof(gliGenericImage));
+  genericImage->width = width;
+  genericImage->height = height;
+  genericImage->format = format;
+  genericImage->components = components;
+  genericImage->pixels = pixels;
+  // CMAP is not supported, but we need to put something here
+  genericImage->cmapEntries = 0;
+  genericImage->cmapFormat = GL_BGR;
+  genericImage->cmap = cmap;
+
+  // write pixels to tga file
+  FILE * imgFile;
+  // "-" as output file name is code for write to stdout
+  if(tga_file.compare("-") == 0)
+  {
+    imgFile = stdout;
+  }else{
+    imgFile = fopen(tga_file.c_str(),"w");
+    if(NULL==imgFile)
+    {
+      printf("IOError: %s could not be opened...\n",tga_file.c_str());
+      return false;
+    }
+  }
+
+  writeTGA(genericImage,imgFile);
+
+  free(genericImage);
+  return fclose(imgFile) == 0;
+}
+
+#ifdef IGL_STATIC_LIBRARY
+// Explicit template instantiation
+#endif

src/igl/copyleft/opengl2/render_to_tga.h

@@ -0,0 +1,38 @@
+// This file is part of libigl, a simple c++ geometry processing library.
+// 
+// Copyright (C) 2014 Alec Jacobson <alecjacobson@gmail.com>
+// 
+// This Source Code Form is subject to the terms of the Mozilla Public License 
+// v. 2.0. If a copy of the MPL was not distributed with this file, You can 
+// obtain one at http://mozilla.org/MPL/2.0/.
+#ifndef IGL_OPENGL_RENDER_TO_TGA_H
+#define IGL_OPENGL_RENDER_TO_TGA_H
+#include "../../igl_inline.h"
+#include <string>
+
+namespace igl
+{
+  namespace opengl
+  {
+    // Render current open GL image to .tga file
+    // Inputs:
+    //   tga_file  path to output .tga file
+    //   width  width of scene and resulting image
+    //   height height of scene and resulting image
+    ///  alpha  whether to include alpha channel
+    // Returns true only if no errors occurred
+    //
+    // See also: png/render_to_png which is slower but writes .png files
+    IGL_INLINE bool render_to_tga(
+      const std::string tga_file,
+      const int width,
+      const int height,
+      const bool alpha);
+  }
+}
+
+#ifndef IGL_STATIC_LIBRARY
+#  include "render_to_tga.cpp"
+#endif
+
+#endif

src/igl/copyleft/opengl2/texture_from_tga.cpp

@@ -0,0 +1,68 @@
+// This file is part of libigl, a simple c++ geometry processing library.
+// 
+// Copyright (C) 2014 Alec Jacobson <alecjacobson@gmail.com>
+// 
+// This Source Code Form is subject to the terms of the Mozilla Public License 
+// v. 2.0. If a copy of the MPL was not distributed with this file, You can 
+// obtain one at http://mozilla.org/MPL/2.0/.
+#include "texture_from_tga.h"
+#include "tga.h"
+#include <cstring>
+
+IGL_INLINE bool igl::opengl::texture_from_tga(const std::string tga_file, GLuint & id)
+{
+  using namespace std;
+
+  // read pixels to tga file
+  FILE * imgFile;
+  // "-" as input file name is code for read from stdin
+  imgFile = fopen(tga_file.c_str(),"r");
+  if(NULL==imgFile)
+  {
+    printf("IOError: %s could not be opened...",tga_file.c_str());
+    return false;
+  }
+
+  // gliReadTGA annoyingly uses char * instead of const char *
+  size_t len = tga_file.length();
+  char* tga_file_char = new char [ len + 1 ];
+  strcpy( tga_file_char, tga_file.c_str() );
+  // read image
+  gliGenericImage* img = gliReadTGA(imgFile, tga_file_char, 0, 0);
+  // clean up filename buffer
+  delete[] tga_file_char;
+  fclose( imgFile );
+
+  // set up texture mapping parameters and generate texture id
+  glGenTextures(1,&id);
+  glBindTexture(GL_TEXTURE_2D, id);
+  // Texture parameters
+  float empty[] = {1.0f,1.0f,1.0f,0.0f};
+  glTexParameterfv(GL_TEXTURE_2D,GL_TEXTURE_BORDER_COLOR,empty);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
+  //glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,
+  //  GL_LINEAR_MIPMAP_NEAREST);
+  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
+    GL_LINEAR);
+
+  // OpenGL by default tries to read data in multiples of 4, if our data is
+  // only RGB or BGR and the width is not divible by 4 then we need to alert
+  // opengl
+  if((img->width % 4) != 0 && 
+   (img->format == GL_RGB || 
+    img->format == GL_BGR))
+  {
+    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+  }
+
+  // Load texture
+  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, img->width,
+    img->height, 0, img->format, GL_UNSIGNED_BYTE,
+    img->pixels);
+  return id;
+}
+
+#ifdef IGL_STATIC_LIBRARY
+// Explicit template instantiation
+#endif

src/igl/copyleft/opengl2/texture_from_tga.h

@@ -0,0 +1,33 @@
+// This file is part of libigl, a simple c++ geometry processing library.
+// 
+// Copyright (C) 2014 Alec Jacobson <alecjacobson@gmail.com>
+// 
+// This Source Code Form is subject to the terms of the Mozilla Public License 
+// v. 2.0. If a copy of the MPL was not distributed with this file, You can 
+// obtain one at http://mozilla.org/MPL/2.0/.
+#ifndef IGL_OPENGL_TEXTURE_FROM_TGA_H
+#define IGL_OPENGL_TEXTURE_FROM_TGA_H
+#include "../../igl_inline.h"
+#include "../../opengl2/gl.h"
+#include <string>
+
+namespace igl
+{
+  namespace opengl
+  {
+    // Read an image from a .tga file and use it as a texture
+    //
+    // Input:
+    //  tga_file  path to .tga file
+    // Output:
+    //  id  of generated openGL texture
+    // Returns true on success, false on failure
+    IGL_INLINE bool texture_from_tga(const std::string tga_file, GLuint & id);
+  }
+}
+
+#ifndef IGL_STATIC_LIBRARY
+#  include "texture_from_tga.cpp"
+#endif
+
+#endif

src/igl/copyleft/opengl2/tga.cpp

@@ -0,0 +1,549 @@
+////////////////////////////////////////////////////////////////////////////////
+//
+// WARNING
+//
+// THIS DOES NOT DEAL WITH VERTICALLY FLIPPED DATA CORRECTLY
+//
+////////////////////////////////////////////////////////////////////////////////
+
+/* This file is derived from (actually an earlier version of)... */
+
+/* The GIMP -- an image manipulation program
+ * Copyright (C) 1995 Spencer Kimball and Peter Mattis
+ *
+ * $Id: tga.cpp,v 1.1.2.5 2007-05-10 02:10:07 elif Exp $
+ * TrueVision Targa loading and saving file filter for the Gimp.
+ * Targa code Copyright (C) 1997 Raphael FRANCOIS and Gordon Matzigkeit
+ *
+ * The Targa reading and writing code was written from scratch by
+ * Raphael FRANCOIS <fraph@ibm.net> and Gordon Matzigkeit
+ * <gord@gnu.ai.mit.edu> based on the TrueVision TGA File Format
+ * Specification, Version 2.0:
+ *
+ *   <URL:ftp://ftp.truevision.com/pub/TGA.File.Format.Spec/>
+ *
+ * It does not contain any code written for other TGA file loaders.
+ * Not even the RLE handling. ;)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include "tga.h"
+#include "../../opengl2/glext.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+
+static char error[256];
+static unsigned int _verbose = 0;
+static int totbytes = 0;
+
+typedef struct {
+  unsigned char *statebuf;
+  int statelen;
+  int laststate;
+} RLEstate;
+
+IGL_INLINE static int
+std_fread(RLEstate * /*rleInfo*/, unsigned char *buf, size_t datasize, size_t nelems, FILE *fp)
+{
+  if (_verbose > 1) {
+    totbytes += nelems * datasize;
+    printf("TGA: std_fread %d (total %d)\n",
+      (int)(nelems * datasize), totbytes);
+  }
+  return fread(buf, datasize, nelems, fp);
+}
+
+#define MIN(a,b) (((a) < (b)) ? (a) : (b))
+
+#define RLE_PACKETSIZE 0x80
+
+/* Decode a bufferful of file. */
+IGL_INLINE static int
+rle_fread(RLEstate *rleInfo, unsigned char *vbuf, size_t datasize, size_t nelems, FILE *fp)
+{
+
+  unsigned char *buf = vbuf;
+  int j, k;
+  int buflen, count, bytes, curbytes;
+  unsigned char *p;
+
+  /* Scale the buffer length. */
+  buflen = nelems * datasize;
+
+  j = 0;
+  curbytes = totbytes;
+  while (j < buflen) {
+    if (rleInfo->laststate < rleInfo->statelen) {
+      /* Copy bytes from our previously decoded buffer. */
+      bytes = MIN(buflen - j, rleInfo->statelen - rleInfo->laststate);
+      memcpy(buf + j, rleInfo->statebuf + rleInfo->laststate, bytes);
+      j += bytes;
+      rleInfo->laststate += bytes;
+
+      /* If we used up all of our state bytes, then reset them. */
+      if (rleInfo->laststate >= rleInfo->statelen) {
+        rleInfo->laststate = 0;
+        rleInfo->statelen = 0;
+      }
+
+      /* If we filled the buffer, then exit the loop. */
+      if (j >= buflen) break;
+    }
+
+    /* Decode the next packet. */
+    count = fgetc(fp);
+    if (count == EOF) {
+      if (_verbose) printf("TGA: hit EOF while looking for count\n");
+      return j / datasize;
+    }
+
+    /* Scale the byte length to the size of the data. */
+    bytes = ((count & ~RLE_PACKETSIZE) + 1) * datasize;
+
+    if (j + bytes <= buflen) {
+      /* We can copy directly into the image buffer. */
+      p = buf + j;
+    } else {
+#ifdef PROFILE
+      printf("TGA: needed to use statebuf for %d bytes\n", buflen - j);
+#endif
+      /* Allocate the state buffer if we haven't already. */
+      if (!rleInfo->statebuf) {
+        rleInfo->statebuf = (unsigned char *) malloc(RLE_PACKETSIZE * datasize);
+      }
+      p = rleInfo->statebuf;
+    }
+
+    if (count & RLE_PACKETSIZE) {
+      /* Fill the buffer with the next value. */
+      if (fread(p, datasize, 1, fp) != 1) {
+        if (_verbose) {
+          printf("TGA: EOF while reading %d/%d element RLE packet\n",
+            bytes, (int)datasize);
+        }
+        return j / datasize;
+      }
+
+      /* Optimized case for single-byte encoded data. */
+      if (datasize == 1) {
+        memset(p + 1, *p, bytes - 1);
+      } else {
+        for (k = datasize; k < bytes; k += datasize) {
+          memcpy(p + k, p, datasize);
+        }
+      }
+    } else {
+      /* Read in the buffer. */
+      if (fread(p, bytes, 1, fp) != 1) {
+        if (_verbose) {
+          printf("TGA: EOF while reading %d/%d element raw packet\n",
+            bytes, (int)datasize);
+        }
+        return j / datasize;
+      }
+    }
+
+    if (_verbose > 1) {
+      totbytes += bytes;
+      if (_verbose > 2) {
+        printf("TGA: %s packet %d/%d\n",
+          (count & RLE_PACKETSIZE) ? "RLE" : "raw",
+          bytes, totbytes);
+      }
+    }
+
+    /* We may need to copy bytes from the state buffer. */
+    if (p == rleInfo->statebuf) {
+      rleInfo->statelen = bytes;
+    } else {
+      j += bytes;
+    }
+  }
+
+  if (_verbose > 1) {
+    printf("TGA: rle_fread %d/%d (total %d)\n",
+    (int) ( nelems * datasize), totbytes - curbytes, totbytes);
+  }
+  return nelems;
+}
+
+IGL_INLINE igl::opengl::gliGenericImage *
+igl::opengl::gliReadTGA(FILE *fp, char *name, int /*hflip*/, int vflip)
+{
+  igl::opengl::TgaHeader tgaHeader;
+  igl::opengl::TgaFooter tgaFooter;
+  char horzrev, vertrev;
+  int width, height, bpp;
+  int start, end, dir;
+  int i, j, k;
+  int pelbytes, wbytes;
+  GLenum format;
+  int components;
+  RLEstate rleRec;
+  RLEstate *rleInfo;
+  int rle;
+  int index, colors, length;
+  GLubyte *cmap, *pixels, *data;
+  int (*myfread)(RLEstate *rleInfo, unsigned char*, size_t, size_t, FILE*);
+  igl::opengl::gliGenericImage *genericImage;
+
+  /* Check the footer. */
+  if (fseek(fp, 0L - sizeof(tgaFooter), SEEK_END)
+      || fread(&tgaFooter, sizeof(tgaFooter), 1, fp) != 1) {
+    sprintf(error, "TGA: Cannot read footer from \"%s\"", name);
+    if (_verbose) printf("%s\n", error);
+    return NULL;
+  }  
+
+  /* Check the signature. */
+  if (memcmp(tgaFooter.signature, TGA_SIGNATURE,
+             sizeof(tgaFooter.signature)) == 0) {
+    if (_verbose) printf("TGA: found New TGA\n");
+  } else {
+    if (_verbose) printf("TGA: found Original TGA\n");
+  }
+
+  if (fseek(fp, 0, SEEK_SET) ||
+      fread(&tgaHeader, sizeof(tgaHeader), 1, fp) != 1) {
+    sprintf(error, "TGA: Cannot read header from \"%s\"", name);
+    if (_verbose) printf("%s\n", error);
+    return NULL;
+  }
+
+  if (_verbose && tgaHeader.idLength) {
+    char *idString = (char*) malloc(tgaHeader.idLength);
+    
+    if (fread(idString, tgaHeader.idLength, 1, fp) != 1) {
+      sprintf(error, "TGA: Cannot read ID field in \"%s\"", name);
+      printf("%s\n", error);
+    } else {
+      printf("TGA: ID field: \"%*s\"\n", tgaHeader.idLength, idString);
+    }
+    free(idString);
+  } else {
+    /* Skip the image ID field. */
+    if (tgaHeader.idLength && fseek(fp, tgaHeader.idLength, SEEK_CUR)) {
+      sprintf(error, "TGA: Cannot skip ID field in \"%s\"", name);
+      if (_verbose) printf("%s\n", error);
+      return NULL;
+    }
+  }
+  
+  /* Reassemble the multi-byte values correctly, regardless of
+     host endianness. */
+  width = (tgaHeader.widthHi << 8) | tgaHeader.widthLo;
+  height = (tgaHeader.heightHi << 8) | tgaHeader.heightLo;
+  bpp = tgaHeader.bpp;
+  if (_verbose) {
+    printf("TGA: width=%d, height=%d, bpp=%d\n", width, height, bpp);
+  }
+
+  horzrev = tgaHeader.descriptor & TGA_DESC_HORIZONTAL;
+  vertrev = tgaHeader.descriptor & TGA_DESC_VERTICAL;
+  //vertrev=0;
+
+//   // JASON - we can force this stuff if we want
+//   if( hflip )
+//       horzrev = 1;
+  if( vflip )
+      vertrev = 1;
+
+  if (_verbose && horzrev) printf("TGA: horizontal reversed\n");
+  if (_verbose && vertrev) printf("TGA: vertical reversed\n");
+
+  rle = 0;
+  switch (tgaHeader.imageType) {
+  case TGA_TYPE_MAPPED_RLE:
+    rle = 1;
+    if (_verbose) printf("TGA: run-length encoded\n");
+  case TGA_TYPE_MAPPED:
+    /* Test for alpha channel. */
+    format = GL_COLOR_INDEX;
+    components = 1;
+    if (_verbose) {
+      printf("TGA: %d bit indexed image (%d bit palette)\n",
+        tgaHeader.colorMapSize, bpp);
+    }
+    break;
+
+  case TGA_TYPE_GRAY_RLE:
+    rle = 1;
+    if (_verbose) printf("TGA: run-length encoded\n");
+  case TGA_TYPE_GRAY:
+    format = GL_LUMINANCE;
+    components = 1;
+    if (_verbose) printf("TGA: %d bit grayscale image\n", bpp);
+    break;
+
+  case TGA_TYPE_COLOR_RLE:
+    rle = 1;
+    if (_verbose) printf("TGA: run-length encoded\n");
+  case TGA_TYPE_COLOR:
+    /* Test for alpha channel. */
+    if (bpp == 32) {
+      format = GL_BGRA_EXT;
+      components = 4;
+      if (_verbose) {
+        printf("TGA: %d bit color image with alpha channel\n", bpp);
+      }
+    } else {
+      format = GL_BGR_EXT;
+      components = 3;
+      if (_verbose) printf("TGA: %d bit color image\n", bpp);
+    }
+    break;
+
+  default:
+    sprintf(error,
+      "TGA: unrecognized image type %d\n", tgaHeader.imageType);
+    if (_verbose) printf("%s\n", error);
+    return NULL;
+  }
+
+  if ((format == GL_BGRA_EXT && bpp != 32) ||
+      (format == GL_BGR_EXT && bpp != 24) ||
+      ((format == GL_LUMINANCE || format == GL_COLOR_INDEX) && bpp != 8)) {
+    /* FIXME: We haven't implemented bit-packed fields yet. */
+    fprintf(stderr, "bpp %d, format %x\n", bpp, (unsigned int)format); 
+    sprintf(error, "TGA: channel sizes other than 8 bits are unimplemented");
+    if (_verbose) printf("%s\n", error);
+    return NULL;
+  }
+
+  /* Check that we have a color map only when we need it. */
+  if (format == GL_COLOR_INDEX) {
+    if (tgaHeader.colorMapType != 1) {
+      sprintf(error, "TGA: indexed image has invalid color map type %d\n",
+        tgaHeader.colorMapType);
+      if (_verbose) printf("%s\n", error);
+      return NULL;
+    }
+  } else if (tgaHeader.colorMapType != 0) {
+    sprintf(error, "TGA: non-indexed image has invalid color map type %d\n",
+      tgaHeader.colorMapType);
+    if (_verbose) printf("%s\n", error);
+    return NULL;
+  }
+
+  if (tgaHeader.colorMapType == 1) {
+    /* We need to read in the colormap. */
+    index = (tgaHeader.colorMapIndexHi << 8) | tgaHeader.colorMapIndexLo;
+    length = (tgaHeader.colorMapLengthHi << 8) | tgaHeader.colorMapLengthLo;
+
+    if (_verbose) {
+      printf("TGA: reading color map (%d + %d) * (%d / 8)\n",
+        index, length, tgaHeader.colorMapSize);
+    }
+    if (length == 0) {
+      sprintf(error, "TGA: invalid color map length %d", length);
+      if (_verbose) printf("%s\n", error);
+      return NULL;
+    }
+    if (tgaHeader.colorMapSize != 24) {
+      /* We haven't implemented bit-packed fields yet. */
+      sprintf(error, "TGA: channel sizes other than 8 bits are unimplemented");
+      if (_verbose) printf("%s\n", error);
+      return NULL;
+    }
+
+    pelbytes = tgaHeader.colorMapSize / 8;
+    colors = length + index;
+    cmap = (GLubyte*)malloc (colors * pelbytes);
+
+    /* Zero the entries up to the beginning of the map. */
+    memset(cmap, 0, index * pelbytes);
+
+    /* Read in the rest of the colormap. */
+    if (fread(cmap, pelbytes, length, fp) != (size_t) length) {
+      sprintf(error, "TGA: error reading colormap (ftell == %ld)\n",
+        ftell (fp));
+      if (_verbose) printf("%s\n", error);
+      return NULL;
+    }
+
+    if (pelbytes >= 3) {
+      /* Rearrange the colors from BGR to RGB. */
+      int tmp;
+      for (j = index; j < length * pelbytes; j += pelbytes) {
+        tmp = cmap[j];
+        cmap[j] = cmap[j + 2];
+        cmap[j + 2] = tmp;
+      }
+    }
+  } else {
+    colors = 0;
+    cmap = NULL;
+  }
+
+  /* Allocate the data. */
+  pelbytes = bpp / 8;
+  pixels = (unsigned char *) malloc (width * height * pelbytes);
+
+  if (rle) {
+    rleRec.statebuf = 0;
+    rleRec.statelen = 0;
+    rleRec.laststate = 0;
+    rleInfo = &rleRec;
+    myfread = rle_fread;
+  } else {
+    rleInfo = NULL;
+    myfread = std_fread;
+  }
+
+  wbytes = width * pelbytes;
+
+  if (vertrev) {
+    start = 0;
+    end = height;
+    dir = 1;
+  } else {
+    /* We need to reverse loading order of rows. */
+    start = height-1;
+    end = -1;
+    dir = -1;
+  }
+
+  for (i = start; i != end; i += dir) {
+    data = pixels + i*wbytes;
+
+    /* Suck in the data one row at a time. */
+    if (myfread(rleInfo, data, pelbytes, width, fp) != width) {
+      /* Probably premature end of file. */
+      if (_verbose) {
+        printf ("TGA: error reading (ftell == %ld, width=%d)\n",
+          ftell(fp), width);
+      }
+      return NULL;
+    }  
+
+    if (horzrev) {
+      /* We need to mirror row horizontally. */
+      for (j = 0; j < width/2; j++) {
+        GLubyte tmp;
+
+        for (k = 0; k < pelbytes; k++) {
+          tmp = data[j*pelbytes+k];
+          data[j*pelbytes+k] = data[(width-j-1)*pelbytes+k];
+          data[(width-j-1)*pelbytes+k] = tmp;
+        }
+      }
+    }
+  }
+
+  if (rle) {
+    free(rleInfo->statebuf);
+  }
+
+  if (fgetc (fp) != EOF) {
+    if (_verbose) printf ("TGA: too much input data, ignoring extra...\n");
+  }
+
+  genericImage = (igl::opengl::gliGenericImage*) malloc(sizeof(igl::opengl::gliGenericImage));
+  genericImage->width = width;
+  genericImage->height = height;
+  genericImage->format = format;
+  genericImage->components = components;
+  genericImage->cmapEntries = colors;
+  genericImage->cmapFormat = GL_BGR_EXT;  // XXX fix me
+  genericImage->cmap = cmap;
+  genericImage->pixels = pixels;
+
+  return genericImage;
+}
+
+IGL_INLINE int igl::opengl::gli_verbose(int new_verbose)
+{
+  _verbose = new_verbose;
+  return _verbose;
+}
+
+
+
+// added 10/2005, Denis Zorin
+// a very simple TGA output, supporting 
+// uncompressed luminance RGB and RGBA 
+// G22.2270 students: this is C (no C++) 
+// so this is not the style I would encourage
+// you to use; I used it for consistency 
+// with the rest of the code in this file 
+
+
+// fixed header values for the subset of TGA we use for writing
+unsigned char TGAHeaderColor[12] = 
+  { 0,// 0 ID length = no id
+    0,// 1 color map type = no color map
+    2,// 2 image type = uncompressed true color
+    0, 0, 0, 0, 0,// color map spec = empty
+    0, 0,  // x origin of image 
+    0, 0   // y origin of image
+  };
+
+unsigned char TGAHeaderBW[12] = 
+  { 0,// 0 ID length = no id
+    0,// 1 color map type = no color map
+    3,// 3 image type = uncompressed black and white
+    0, 0, 0, 0, 0,// color map spec = empty
+    0, 0,  // x origin of image 
+    0, 0   // y origin of image
+  };
+
+// this makes sure that 
+// image size is written in correct format 
+// and byte order (least first)
+IGL_INLINE void write16bit(int n, FILE* fp) { 
+  unsigned char bytes[] = { static_cast<unsigned char>(n % 256), static_cast<unsigned char>(n / 256) };
+  fwrite(bytes, 2, sizeof(unsigned char),fp);
+}
+
+
+
+IGL_INLINE void igl::opengl::writeTGA( igl::opengl::gliGenericImage* image, FILE *fp) {
+
+  assert(!image->cmap); // we do not deal with color map images
+    
+  if(image->components == 3 || image->components == 4) 
+    fwrite(TGAHeaderColor, 12, sizeof(unsigned char),fp);
+  else { 
+    if(image->components == 1 ) 
+      fwrite(TGAHeaderBW, 12, sizeof(unsigned char),fp);        
+    else { fprintf(stderr,"Supported component number: 1,3 or 4\n"); exit(1); }
+  }
+
+  write16bit(image->width,fp);  
+  write16bit(image->height,fp);  
+  switch (image->components ) { 
+  case 1: 
+    putc(8,fp);
+    break;
+  case 3: 
+    putc(24,fp); 
+    break;
+  case 4:
+    putc(32,fp);
+    break;
+  default: fprintf(stderr,"Supported component number: 1,3 or 4\n"); exit(1); 
+  };
+  
+  if(image-> components == 4) 
+    putc(0x04,fp); // bottom left image (0x00) + 8 bit alpha (0x4)
+  else 
+    putc(0x00,fp);
+
+  fwrite(image->pixels, image->height*image->width*image->components, sizeof(char),fp);
+}
+

src/igl/copyleft/opengl2/tga.h

@@ -0,0 +1,106 @@
+// This file is part of libigl, a simple c++ geometry processing library.
+// 
+// Copyright (C) 2015 Alec Jacobson <alecjacobson@gmail.com>
+// 
+// This Source Code Form is subject to the terms of the Mozilla Public License 
+// v. 2.0. If a copy of the MPL was not distributed with this file, You can 
+// obtain one at http://mozilla.org/MPL/2.0/.
+#ifndef IGL_OPENGL_TGA_H
+#define IGL_OPENGL_TGA_H
+#include "../../igl_inline.h"
+
+#include "../../opengl2/gl.h"
+// See license in tga.cpp
+/* tga.h - interface for TrueVision (TGA) image file loader */
+#include <stdio.h>
+#ifdef _WIN32
+#include <windows.h>
+#endif
+
+namespace igl
+{
+namespace opengl
+{
+
+typedef struct {
+
+  GLsizei  width;
+  GLsizei  height;
+  GLint    components;
+  GLenum   format;
+
+  GLsizei  cmapEntries;
+  GLenum   cmapFormat;
+  GLubyte *cmap;
+
+  GLubyte *pixels;
+  
+} gliGenericImage;
+
+typedef struct {
+  unsigned char idLength;
+  unsigned char colorMapType;
+
+  /* The image type. */
+#define TGA_TYPE_MAPPED 1
+#define TGA_TYPE_COLOR 2
+#define TGA_TYPE_GRAY 3
+#define TGA_TYPE_MAPPED_RLE 9
+#define TGA_TYPE_COLOR_RLE 10
+#define TGA_TYPE_GRAY_RLE 11
+  unsigned char imageType;
+
+  /* Color Map Specification. */
+  /* We need to separately specify high and low bytes to avoid endianness
+     and alignment problems. */
+  unsigned char colorMapIndexLo, colorMapIndexHi;
+  unsigned char colorMapLengthLo, colorMapLengthHi;
+  unsigned char colorMapSize;
+
+  /* Image Specification. */
+  unsigned char xOriginLo, xOriginHi;
+  unsigned char yOriginLo, yOriginHi;
+
+  unsigned char widthLo, widthHi;
+  unsigned char heightLo, heightHi;
+
+  unsigned char bpp;
+
+  /* Image descriptor.
+     3-0: attribute bpp
+     4:   left-to-right ordering
+     5:   top-to-bottom ordering
+     7-6: zero
+     */
+#define TGA_DESC_ABITS 0x0f
+#define TGA_DESC_HORIZONTAL 0x10
+#define TGA_DESC_VERTICAL 0x20
+  unsigned char descriptor;
+
+} TgaHeader;
+
+typedef struct {
+  unsigned int extensionAreaOffset;
+  unsigned int developerDirectoryOffset;
+#define TGA_SIGNATURE "TRUEVISION-XFILE"
+  char signature[16];
+  char dot;
+  char null;
+} TgaFooter;
+
+IGL_INLINE extern gliGenericImage *gliReadTGA(FILE *fp, char *name, int hflip, int vflip);
+IGL_INLINE int gli_verbose(int new_verbose);
+IGL_INLINE extern int gliVerbose(int newVerbose);
+
+IGL_INLINE void writeTGA( gliGenericImage* image, FILE *fp);
+
+
+
+} // end of igl namespace
+}
+
+#ifndef IGL_STATIC_LIBRARY
+#  include "tga.cpp"
+#endif
+
+#endif