1 files changed, 405 insertions, 0 deletions
diff --git a/src/engine/external/glfw/lib/tga.c b/src/engine/external/glfw/lib/tga.c
new file mode 100644
index 00000000..51e73844
--- /dev/null
+++ b/src/engine/external/glfw/lib/tga.c
@@ -0,0 +1,405 @@
+//========================================================================
+// GLFW - An OpenGL framework
+// File:        tga.c
+// Platform:    Any
+// API version: 2.6
+// WWW:         http://glfw.sourceforge.net
+//------------------------------------------------------------------------
+// Copyright (c) 2002-2006 Camilla Berglund
+//
+// This software is provided 'as-is', without any express or implied
+// warranty. In no event will the authors be held liable for any damages
+// arising from the use of this software.
+//
+// Permission is granted to anyone to use this software for any purpose,
+// including commercial applications, and to alter it and redistribute it
+// freely, subject to the following restrictions:
+//
+// 1. The origin of this software must not be misrepresented; you must not
+//    claim that you wrote the original software. If you use this software
+//    in a product, an acknowledgment in the product documentation would
+//    be appreciated but is not required.
+//
+// 2. Altered source versions must be plainly marked as such, and must not
+//    be misrepresented as being the original software.
+//
+// 3. This notice may not be removed or altered from any source
+//    distribution.
+//
+//========================================================================
+
+//========================================================================
+// Description:
+//
+// TGA format image file loader. This module supports version 1 Targa
+// images, with these restrictions:
+//  - Pixel format may only be 8, 24 or 32 bits
+//  - Colormaps must be no longer than 256 entries
+//
+//========================================================================
+
+
+#include "internal.h"
+
+
+//************************************************************************
+//****            GLFW internal functions & declarations              ****
+//************************************************************************
+
+//========================================================================
+// TGA file header information
+//========================================================================
+
+typedef struct {
+    int idlen;                 // 1 byte
+    int cmaptype;              // 1 byte
+    int imagetype;             // 1 byte
+    int cmapfirstidx;          // 2 bytes
+    int cmaplen;               // 2 bytes
+    int cmapentrysize;         // 1 byte
+    int xorigin;               // 2 bytes
+    int yorigin;               // 2 bytes
+    int width;                 // 2 bytes
+    int height;                // 2 bytes
+    int bitsperpixel;          // 1 byte
+    int imageinfo;             // 1 byte
+    int _alphabits;            // (derived from imageinfo)
+    int _origin;               // (derived from imageinfo)
+} _tga_header_t;
+
+#define _TGA_CMAPTYPE_NONE      0
+#define _TGA_CMAPTYPE_PRESENT   1
+
+#define _TGA_IMAGETYPE_NONE     0
+#define _TGA_IMAGETYPE_CMAP     1
+#define _TGA_IMAGETYPE_TC       2
+#define _TGA_IMAGETYPE_GRAY     3
+#define _TGA_IMAGETYPE_CMAP_RLE 9
+#define _TGA_IMAGETYPE_TC_RLE   10
+#define _TGA_IMAGETYPE_GRAY_RLE 11
+
+#define _TGA_IMAGEINFO_ALPHA_MASK   0x0f
+#define _TGA_IMAGEINFO_ALPHA_SHIFT  0
+#define _TGA_IMAGEINFO_ORIGIN_MASK  0x30
+#define _TGA_IMAGEINFO_ORIGIN_SHIFT 4
+
+#define _TGA_ORIGIN_BL 0
+#define _TGA_ORIGIN_BR 1
+#define _TGA_ORIGIN_UL 2
+#define _TGA_ORIGIN_UR 3
+
+
+//========================================================================
+// _glfwReadTGAHeader() - Read TGA file header (and check that it is
+// valid)
+//========================================================================
+
+static int _glfwReadTGAHeader( _GLFWstream *s, _tga_header_t *h )
+{
+    unsigned char buf[ 18 ];
+    int pos;
+
+    // Read TGA file header from file
+    pos = _glfwTellStream( s );
+    _glfwReadStream( s, buf, 18 );
+
+    // Interpret header (endian independent parsing)
+    h->idlen         = (int) buf[0];
+    h->cmaptype      = (int) buf[1];
+    h->imagetype     = (int) buf[2];
+    h->cmapfirstidx  = (int) buf[3] | (((int) buf[4]) << 8);
+    h->cmaplen       = (int) buf[5] | (((int) buf[6]) << 8);
+    h->cmapentrysize = (int) buf[7];
+    h->xorigin       = (int) buf[8] | (((int) buf[9]) << 8);
+    h->yorigin       = (int) buf[10] | (((int) buf[11]) << 8);
+    h->width         = (int) buf[12] | (((int) buf[13]) << 8);
+    h->height        = (int) buf[14] | (((int) buf[15]) << 8);
+    h->bitsperpixel  = (int) buf[16];
+    h->imageinfo     = (int) buf[17];
+
+    // Extract alphabits and origin information
+    h->_alphabits = (int) (h->imageinfo & _TGA_IMAGEINFO_ALPHA_MASK) >>
+                     _TGA_IMAGEINFO_ALPHA_SHIFT;
+    h->_origin    = (int) (h->imageinfo & _TGA_IMAGEINFO_ORIGIN_MASK) >>
+                     _TGA_IMAGEINFO_ORIGIN_SHIFT;
+
+    // Validate TGA header (is this a TGA file?)
+    if( (h->cmaptype == 0 || h->cmaptype == 1) &&
+        ((h->imagetype >= 1 && h->imagetype <= 3) ||
+         (h->imagetype >= 9 && h->imagetype <= 11)) &&
+         (h->bitsperpixel == 8 || h->bitsperpixel == 24 ||
+          h->bitsperpixel == 32) )
+    {
+        // Skip the ID field
+        _glfwSeekStream( s, h->idlen, SEEK_CUR );
+
+        // Indicate that the TGA header was valid
+        return GL_TRUE;
+    }
+    else
+    {
+        // Restore file position
+        _glfwSeekStream( s, pos, SEEK_SET );
+
+        // Indicate that the TGA header was invalid
+        return GL_FALSE;
+    }
+}
+
+//========================================================================
+// _glfwReadTGA_RLE() - Read Run-Length Encoded data
+//========================================================================
+
+static void _glfwReadTGA_RLE( unsigned char *buf, int size, int bpp,
+    _GLFWstream *s )
+{
+    int repcount, bytes, k, n;
+    unsigned char pixel[ 4 ];
+    char c;
+
+    // Dummy check
+    if( bpp > 4 )
+    {
+        return;
+    }
+
+    while( size > 0 )
+    {
+        // Get repetition count
+	_glfwReadStream( s, &c, 1 );
+        repcount = (unsigned int) c;
+        bytes = ((repcount & 127) + 1) * bpp;
+        if( size < bytes )
+        {
+            bytes = size;
+        }
+
+        // Run-Length packet?
+        if( repcount & 128 )
+        {
+            _glfwReadStream( s, pixel, bpp );
+            for( n = 0; n < (repcount & 127) + 1; n ++ )
+            {
+                for( k = 0; k < bpp; k ++ )
+                {
+                    *buf ++ = pixel[ k ];
+                }
+            }
+        }
+        else
+        {
+            // It's a Raw packet
+            _glfwReadStream( s, buf, bytes );
+            buf += bytes;
+        }
+
+        size -= bytes;
+    }
+}
+
+
+//========================================================================
+// _glfwReadTGA() - Read a TGA image from a file
+//========================================================================
+
+int _glfwReadTGA( _GLFWstream *s, GLFWimage *img, int flags )
+{
+    _tga_header_t h;
+    unsigned char *cmap, *pix, tmp, *src, *dst;
+    int cmapsize, pixsize, pixsize2;
+    int bpp, bpp2, k, m, n, swapx, swapy;
+
+    // Read TGA header
+    if( !_glfwReadTGAHeader( s, &h ) )
+    {
+        return 0;
+    }
+
+    // Is there a colormap?
+    cmapsize = (h.cmaptype == _TGA_CMAPTYPE_PRESENT ? 1 : 0) * h.cmaplen *
+               ((h.cmapentrysize+7) / 8);
+    if( cmapsize > 0 )
+    {
+        // Is it a colormap that we can handle?
+        if( (h.cmapentrysize != 24 && h.cmapentrysize != 32) ||
+            h.cmaplen == 0 || h.cmaplen > 256 )
+        {
+            return 0;
+        }
+
+        // Allocate memory for colormap
+        cmap = (unsigned char *) malloc( cmapsize );
+        if( cmap == NULL )
+        {
+            return 0;
+        }
+
+        // Read colormap from file
+        _glfwReadStream( s, cmap, cmapsize );
+    }
+    else
+    {
+        cmap = NULL;
+    }
+
+    // Size of pixel data
+    pixsize = h.width * h.height * ((h.bitsperpixel + 7) / 8);
+
+    // Bytes per pixel (pixel data - unexpanded)
+    bpp = (h.bitsperpixel + 7) / 8;
+
+    // Bytes per pixel (expanded pixels - not colormap indeces)
+    if( cmap )
+    {
+        bpp2 = (h.cmapentrysize + 7) / 8;
+    }
+    else
+    {
+        bpp2 = bpp;
+    }
+
+    // For colormaped images, the RGB/RGBA image data may use more memory
+    // than the stored pixel data
+    pixsize2 = h.width * h.height * bpp2;
+
+    // Allocate memory for pixel data
+    pix = (unsigned char *) malloc( pixsize2 );
+    if( pix == NULL )
+    {
+        if( cmap )
+        {
+            free( cmap );
+        }
+        return 0;
+    }
+
+    // Read pixel data from file
+    if( h.imagetype >= _TGA_IMAGETYPE_CMAP_RLE )
+    {
+        _glfwReadTGA_RLE( pix, pixsize, bpp, s );
+    }
+    else
+    {
+        _glfwReadStream( s, pix, pixsize );
+    }
+
+    // If the image origin is not what we want, re-arrange the pixels
+    switch( h._origin )
+    {
+    default:
+    case _TGA_ORIGIN_UL:
+        swapx = 0;
+        swapy = 1;
+        break;
+
+    case _TGA_ORIGIN_BL:
+        swapx = 0;
+        swapy = 0;
+        break;
+
+    case _TGA_ORIGIN_UR:
+        swapx = 1;
+        swapy = 1;
+        break;
+
+    case _TGA_ORIGIN_BR:
+        swapx = 1;
+        swapy = 0;
+        break;
+    }
+    if( (swapy && !(flags & GLFW_ORIGIN_UL_BIT)) ||
+        (!swapy && (flags & GLFW_ORIGIN_UL_BIT)) )
+    {
+        src = pix;
+        dst = &pix[ (h.height-1)*h.width*bpp ];
+        for( n = 0; n < h.height/2; n ++ )
+        {
+            for( m = 0; m < h.width ; m ++ )
+            {
+                for( k = 0; k < bpp; k ++ )
+                {
+                    tmp     = *src;
+                    *src ++ = *dst;
+                    *dst ++ = tmp;
+                }
+            }
+            dst -= 2*h.width*bpp;
+        }
+    }
+    if( swapx )
+    {
+        src = pix;
+        dst = &pix[ (h.width-1)*bpp ];
+        for( n = 0; n < h.height; n ++ )
+        {
+            for( m = 0; m < h.width/2 ; m ++ )
+            {
+                for( k = 0; k < bpp; k ++ )
+                {
+                    tmp     = *src;
+                    *src ++ = *dst;
+                    *dst ++ = tmp;
+                }
+                dst -= 2*bpp;
+            }
+            src += ((h.width+1)/2)*bpp;
+            dst += ((3*h.width+1)/2)*bpp;
+        }
+    }
+
+    // Convert BGR/BGRA to RGB/RGBA, and optionally colormap indeces to
+    // RGB/RGBA values
+    if( cmap )
+    {
+        // Convert colormap pixel format (BGR -> RGB or BGRA -> RGBA)
+        if( bpp2 == 3 || bpp2 == 4 )
+        {
+            for( n = 0; n < h.cmaplen; n ++ )
+            {
+                tmp                = cmap[ n*bpp2 ];
+                cmap[ n*bpp2 ]     = cmap[ n*bpp2 + 2 ];
+                cmap[ n*bpp2 + 2 ] = tmp;
+            }
+        }
+
+        // Convert pixel data to RGB/RGBA data
+        for( m = h.width * h.height - 1; m >= 0; m -- )
+        {
+            n = pix[ m ];
+            for( k = 0; k < bpp2; k ++ )
+            {
+                pix[ m*bpp2 + k ] = cmap[ n*bpp2 + k ];
+            }
+        }
+
+        // Free memory for colormap (it's not needed anymore)
+        free( cmap );
+    }
+    else
+    {
+        // Convert image pixel format (BGR -> RGB or BGRA -> RGBA)
+        if( bpp2 == 3 || bpp2 == 4 )
+        {
+            src = pix;
+            dst = &pix[ 2 ];
+            for( n = 0; n < h.height * h.width; n ++ )
+            {
+                tmp  = *src;
+                *src = *dst;
+                *dst = tmp;
+                src += bpp2;
+                dst += bpp2;
+            }
+        }
+    }
+
+    // Fill out GLFWimage struct (the Format field will be set by
+    // glfwReadImage)
+    img->Width         = h.width;
+    img->Height        = h.height;
+    img->BytesPerPixel = bpp2;
+    img->Data          = pix;
+
+    return 1;
+}
+