xfont.c revision 35c4bbdf 
1/*
2 * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008)
3 * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice including the dates of first publication and
13 * either this permission notice or a reference to
14 * http://oss.sgi.com/projects/FreeB/
15 * shall be included in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
21 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
22 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
23 * SOFTWARE.
24 *
25 * Except as contained in this notice, the name of Silicon Graphics, Inc.
26 * shall not be used in advertising or otherwise to promote the sale, use or
27 * other dealings in this Software without prior written authorization from
28 * Silicon Graphics, Inc.
29 */
30
31#ifdef HAVE_DIX_CONFIG_H
32#include <dix-config.h>
33#endif
34
35#include "glxserver.h"
36#include "glxutil.h"
37#include "unpack.h"
38#include "indirect_dispatch.h"
39#include <GL/gl.h>
40#include <pixmapstr.h>
41#include <windowstr.h>
42#include <dixfontstr.h>
43
44/*
45** Make a single GL bitmap from a single X glyph
46*/
47static int
48__glXMakeBitmapFromGlyph(FontPtr font, CharInfoPtr pci)
49{
50    int i, j;
51    int widthPadded;            /* width of glyph in bytes, as padded by X */
52    int allocBytes;             /* bytes to allocate to store bitmap */
53    int w;                      /* width of glyph in bits */
54    int h;                      /* height of glyph */
55    register unsigned char *pglyph;
56    register unsigned char *p;
57    unsigned char *allocbuf;
58
59#define __GL_CHAR_BUF_SIZE 2048
60    unsigned char buf[__GL_CHAR_BUF_SIZE];
61
62    w = GLYPHWIDTHPIXELS(pci);
63    h = GLYPHHEIGHTPIXELS(pci);
64    widthPadded = GLYPHWIDTHBYTESPADDED(pci);
65
66    /*
67     ** Use the local buf if possible, otherwise malloc.
68     */
69    allocBytes = widthPadded * h;
70    if (allocBytes <= __GL_CHAR_BUF_SIZE) {
71        p = buf;
72        allocbuf = 0;
73    }
74    else {
75        p = (unsigned char *) malloc(allocBytes);
76        if (!p)
77            return BadAlloc;
78        allocbuf = p;
79    }
80
81    /*
82     ** We have to reverse the picture, top to bottom
83     */
84
85    pglyph = FONTGLYPHBITS(FONTGLYPHS(font), pci) + (h - 1) * widthPadded;
86    for (j = 0; j < h; j++) {
87        for (i = 0; i < widthPadded; i++) {
88            p[i] = pglyph[i];
89        }
90        pglyph -= widthPadded;
91        p += widthPadded;
92    }
93    glBitmap(w, h, -pci->metrics.leftSideBearing, pci->metrics.descent,
94             pci->metrics.characterWidth, 0, allocbuf ? allocbuf : buf);
95
96    free(allocbuf);
97    return Success;
98#undef __GL_CHAR_BUF_SIZE
99}
100
101/*
102** Create a GL bitmap for each character in the X font.  The bitmap is stored
103** in a display list.
104*/
105
106static int
107MakeBitmapsFromFont(FontPtr pFont, int first, int count, int list_base)
108{
109    unsigned long i, nglyphs;
110    CARD8 chs[2];               /* the font index we are going after */
111    CharInfoPtr pci;
112    int rv;                     /* return value */
113    int encoding = (FONTLASTROW(pFont) == 0) ? Linear16Bit : TwoD16Bit;
114
115    glPixelStorei(GL_UNPACK_SWAP_BYTES, FALSE);
116    glPixelStorei(GL_UNPACK_LSB_FIRST, BITMAP_BIT_ORDER == LSBFirst);
117    glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
118    glPixelStorei(GL_UNPACK_SKIP_ROWS, 0);
119    glPixelStorei(GL_UNPACK_SKIP_PIXELS, 0);
120    glPixelStorei(GL_UNPACK_ALIGNMENT, GLYPHPADBYTES);
121    for (i = 0; i < count; i++) {
122        chs[0] = (first + i) >> 8;      /* high byte is first byte */
123        chs[1] = first + i;
124
125        (*pFont->get_glyphs) (pFont, 1, chs, (FontEncoding) encoding,
126                              &nglyphs, &pci);
127
128        /*
129         ** Define a display list containing just a glBitmap() call.
130         */
131        glNewList(list_base + i, GL_COMPILE);
132        if (nglyphs) {
133            rv = __glXMakeBitmapFromGlyph(pFont, pci);
134            if (rv) {
135                return rv;
136            }
137        }
138        glEndList();
139    }
140    return Success;
141}
142
143/************************************************************************/
144
145int
146__glXDisp_UseXFont(__GLXclientState * cl, GLbyte * pc)
147{
148    ClientPtr client = cl->client;
149    xGLXUseXFontReq *req;
150    FontPtr pFont;
151    GLuint currentListIndex;
152    __GLXcontext *cx;
153    int error;
154
155    REQUEST_SIZE_MATCH(xGLXUseXFontReq);
156
157    req = (xGLXUseXFontReq *) pc;
158    cx = __glXForceCurrent(cl, req->contextTag, &error);
159    if (!cx) {
160        return error;
161    }
162
163    glGetIntegerv(GL_LIST_INDEX, (GLint *) &currentListIndex);
164    if (currentListIndex != 0) {
165        /*
166         ** A display list is currently being made.  It is an error
167         ** to try to make a font during another lists construction.
168         */
169        client->errorValue = cx->id;
170        return __glXError(GLXBadContextState);
171    }
172
173    /*
174     ** Font can actually be either the ID of a font or the ID of a GC
175     ** containing a font.
176     */
177
178    error = dixLookupFontable(&pFont, req->font, client, DixReadAccess);
179    if (error != Success)
180        return error;
181
182    return MakeBitmapsFromFont(pFont, req->first, req->count, req->listBase);
183}
184