1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/libs/drawtext/drawgl.c	Sun May 31 00:40:26 2015 +0300
     1.3 @@ -0,0 +1,302 @@
     1.4 +/*
     1.5 +libdrawtext - a simple library for fast text rendering in OpenGL
     1.6 +Copyright (C) 2011-2012  John Tsiombikas <nuclear@member.fsf.org>
     1.7 +
     1.8 +This program is free software: you can redistribute it and/or modify
     1.9 +it under the terms of the GNU Lesser General Public License as published by
    1.10 +the Free Software Foundation, either version 3 of the License, or
    1.11 +(at your option) any later version.
    1.12 +
    1.13 +This program is distributed in the hope that it will be useful,
    1.14 +but WITHOUT ANY WARRANTY; without even the implied warranty of
    1.15 +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    1.16 +GNU Lesser General Public License for more details.
    1.17 +
    1.18 +You should have received a copy of the GNU Lesser General Public License
    1.19 +along with this program.  If not, see <http://www.gnu.org/licenses/>.
    1.20 +*/
    1.21 +#ifndef NO_OPENGL
    1.22 +#include <stdarg.h>
    1.23 +#include <math.h>
    1.24 +#include <ctype.h>
    1.25 +
    1.26 +#include <stdlib.h>
    1.27 +
    1.28 +#ifndef _MSC_VER
    1.29 +#include <alloca.h>
    1.30 +#else
    1.31 +#include <malloc.h>
    1.32 +#endif
    1.33 +
    1.34 +#ifdef TARGET_IPHONE
    1.35 +#include <OpenGLES/ES2/gl.h>
    1.36 +#define GL_ES
    1.37 +#elif defined(ANDROID)
    1.38 +#include <GLES2/gl2.h>
    1.39 +#define GL_ES
    1.40 +#else
    1.41 +#include <GL/glew.h>
    1.42 +#endif
    1.43 +
    1.44 +#include "drawtext.h"
    1.45 +#include "drawtext_impl.h"
    1.46 +
    1.47 +struct vertex {
    1.48 +	float x, y;
    1.49 +	float s, t;
    1.50 +};
    1.51 +
    1.52 +struct quad {
    1.53 +	struct vertex v[6];
    1.54 +};
    1.55 +
    1.56 +static void cleanup(void);
    1.57 +static void add_glyph(struct glyph *g, float x, float y);
    1.58 +
    1.59 +#define QBUF_SZ		512
    1.60 +static struct quad *qbuf;
    1.61 +static int num_quads;
    1.62 +static int vattr = -1;
    1.63 +static int tattr = -1;
    1.64 +static unsigned int font_tex;
    1.65 +static int buf_mode = DTX_NBF;
    1.66 +
    1.67 +
    1.68 +int dtx_gl_init(void)
    1.69 +{
    1.70 +	if(qbuf) {
    1.71 +		return 0;	/* already initialized */
    1.72 +	}
    1.73 +
    1.74 +#ifdef __glew_h__
    1.75 +	glewInit();
    1.76 +#endif
    1.77 +
    1.78 +	if(!(qbuf = malloc(QBUF_SZ * sizeof *qbuf))) {
    1.79 +		return -1;
    1.80 +	}
    1.81 +	num_quads = 0;
    1.82 +
    1.83 +	atexit(cleanup);
    1.84 +	return 0;
    1.85 +}
    1.86 +
    1.87 +static void cleanup(void)
    1.88 +{
    1.89 +	free(qbuf);
    1.90 +}
    1.91 +
    1.92 +
    1.93 +void dtx_vertex_attribs(int vert_attr, int tex_attr)
    1.94 +{
    1.95 +	vattr = vert_attr;
    1.96 +	tattr = tex_attr;
    1.97 +}
    1.98 +
    1.99 +static void set_glyphmap_texture(struct dtx_glyphmap *gmap)
   1.100 +{
   1.101 +	if(!gmap->tex) {
   1.102 +		glGenTextures(1, &gmap->tex);
   1.103 +		glBindTexture(GL_TEXTURE_2D, gmap->tex);
   1.104 +		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
   1.105 +		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
   1.106 +		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
   1.107 +		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
   1.108 +
   1.109 +#ifdef GL_ES
   1.110 +		glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, gmap->xsz, gmap->ysz, 0, GL_ALPHA, GL_UNSIGNED_BYTE, gmap->pixels);
   1.111 +		glGenerateMipmap(GL_TEXTURE_2D);
   1.112 +#else
   1.113 +		gluBuild2DMipmaps(GL_TEXTURE_2D, GL_ALPHA, gmap->xsz, gmap->ysz, GL_ALPHA, GL_UNSIGNED_BYTE, gmap->pixels);
   1.114 +#endif
   1.115 +	}
   1.116 +
   1.117 +	if(font_tex != gmap->tex) {
   1.118 +		dtx_flush();
   1.119 +	}
   1.120 +	font_tex = gmap->tex;
   1.121 +}
   1.122 +
   1.123 +void dtx_glyph(int code)
   1.124 +{
   1.125 +	struct dtx_glyphmap *gmap;
   1.126 +
   1.127 +	if(!dtx_font || !(gmap = dtx_get_font_glyphmap(dtx_font, dtx_font_sz, code))) {
   1.128 +		return;
   1.129 +	}
   1.130 +	set_glyphmap_texture(gmap);
   1.131 +
   1.132 +	add_glyph(gmap->glyphs + code - gmap->cstart, 0, 0);
   1.133 +	dtx_flush();
   1.134 +}
   1.135 +
   1.136 +static const char *put_char(const char *str, float *pos_x, float *pos_y, int *should_flush)
   1.137 +{
   1.138 +	struct dtx_glyphmap *gmap;
   1.139 +	float px, py;
   1.140 +	int code = dtx_utf8_char_code(str);
   1.141 +	str = dtx_utf8_next_char((char*)str);
   1.142 +
   1.143 +	if(buf_mode == DTX_LBF && code == '\n') {
   1.144 +		*should_flush = 1;
   1.145 +	}
   1.146 +
   1.147 +	px = *pos_x;
   1.148 +	py = *pos_y;
   1.149 +
   1.150 +	if((gmap = dtx_proc_char(code, pos_x, pos_y))) {
   1.151 +		int idx = code - gmap->cstart;
   1.152 +
   1.153 +		set_glyphmap_texture(gmap);
   1.154 +		add_glyph(gmap->glyphs + idx, px, py);
   1.155 +	}
   1.156 +	return str;
   1.157 +}
   1.158 +
   1.159 +void dtx_string(const char *str)
   1.160 +{
   1.161 +	int should_flush = buf_mode == DTX_NBF;
   1.162 +	float pos_x = 0.0f;
   1.163 +	float pos_y = 0.0f;
   1.164 +
   1.165 +	if(!dtx_font) {
   1.166 +		return;
   1.167 +	}
   1.168 +
   1.169 +	while(*str) {
   1.170 +		str = put_char(str, &pos_x, &pos_y, &should_flush);
   1.171 +	}
   1.172 +
   1.173 +	if(should_flush) {
   1.174 +		dtx_flush();
   1.175 +	}
   1.176 +}
   1.177 +
   1.178 +void dtx_printf(const char *fmt, ...)
   1.179 +{
   1.180 +	va_list ap;
   1.181 +	int buf_size;
   1.182 +	char *buf, tmp;
   1.183 +
   1.184 +	if(!dtx_font) {
   1.185 +		return;
   1.186 +	}
   1.187 +
   1.188 +	va_start(ap, fmt);
   1.189 +	buf_size = vsnprintf(&tmp, 0, fmt, ap);
   1.190 +	va_end(ap);
   1.191 +
   1.192 +	if(buf_size == -1) {
   1.193 +		buf_size = 512;
   1.194 +	}
   1.195 +
   1.196 +	buf = alloca(buf_size + 1);
   1.197 +	va_start(ap, fmt);
   1.198 +	vsnprintf(buf, buf_size + 1, fmt, ap);
   1.199 +	va_end(ap);
   1.200 +
   1.201 +	dtx_string(buf);
   1.202 +}
   1.203 +
   1.204 +static void qvertex(struct vertex *v, float x, float y, float s, float t)
   1.205 +{
   1.206 +	v->x = x;
   1.207 +	v->y = y;
   1.208 +	v->s = s;
   1.209 +	v->t = t;
   1.210 +}
   1.211 +
   1.212 +static void add_glyph(struct glyph *g, float x, float y)
   1.213 +{
   1.214 +	struct quad *qptr = qbuf + num_quads;
   1.215 +
   1.216 +	x -= g->orig_x;
   1.217 +	y -= g->orig_y;
   1.218 +
   1.219 +	qvertex(qptr->v + 0, x, y, g->nx, g->ny + g->nheight);
   1.220 +	qvertex(qptr->v + 1, x + g->width, y, g->nx + g->nwidth, g->ny + g->nheight);
   1.221 +	qvertex(qptr->v + 2, x + g->width, y + g->height, g->nx + g->nwidth, g->ny);
   1.222 +
   1.223 +	qvertex(qptr->v + 3, x, y, g->nx, g->ny + g->nheight);
   1.224 +	qvertex(qptr->v + 4, x + g->width, y + g->height, g->nx + g->nwidth, g->ny);
   1.225 +	qvertex(qptr->v + 5, x, y + g->height, g->nx, g->ny);
   1.226 +
   1.227 +	if(++num_quads >= QBUF_SZ) {
   1.228 +		dtx_flush();
   1.229 +	}
   1.230 +}
   1.231 +
   1.232 +void dtx_flush(void)
   1.233 +{
   1.234 +	int vbo;
   1.235 +
   1.236 +	if(!num_quads) {
   1.237 +		return;
   1.238 +	}
   1.239 +
   1.240 +	glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &vbo);
   1.241 +	glBindBuffer(GL_ARRAY_BUFFER, 0);
   1.242 +
   1.243 +#ifndef GL_ES
   1.244 +	glPushAttrib(GL_ENABLE_BIT);
   1.245 +	glEnable(GL_TEXTURE_2D);
   1.246 +#endif
   1.247 +	glBindTexture(GL_TEXTURE_2D, font_tex);
   1.248 +
   1.249 +	if(vattr != -1) {
   1.250 +		glEnableVertexAttribArray(vattr);
   1.251 +		glVertexAttribPointer(vattr, 2, GL_FLOAT, 0, sizeof(struct vertex), qbuf);
   1.252 +#ifndef GL_ES
   1.253 +	} else {
   1.254 +		glEnableClientState(GL_VERTEX_ARRAY);
   1.255 +		glVertexPointer(2, GL_FLOAT, sizeof(struct vertex), qbuf);
   1.256 +#endif
   1.257 +	}
   1.258 +	if(tattr != -1) {
   1.259 +		glEnableVertexAttribArray(tattr);
   1.260 +		glVertexAttribPointer(tattr, 2, GL_FLOAT, 0, sizeof(struct vertex), &qbuf->v[0].s);
   1.261 +#ifndef GL_ES
   1.262 +	} else {
   1.263 +		glEnableClientState(GL_TEXTURE_COORD_ARRAY);
   1.264 +		glTexCoordPointer(2, GL_FLOAT, sizeof(struct vertex), &qbuf->v[0].s);
   1.265 +#endif
   1.266 +	}
   1.267 +
   1.268 +	glEnable(GL_BLEND);
   1.269 +	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
   1.270 +
   1.271 +	glDepthMask(0);
   1.272 +
   1.273 +	glDrawArrays(GL_TRIANGLES, 0, num_quads * 6);
   1.274 +
   1.275 +	glDepthMask(1);
   1.276 +
   1.277 +	if(vattr != -1) {
   1.278 +		glDisableVertexAttribArray(vattr);
   1.279 +#ifndef GL_ES
   1.280 +	} else {
   1.281 +		glDisableClientState(GL_VERTEX_ARRAY);
   1.282 +#endif
   1.283 +	}
   1.284 +	if(tattr != -1) {
   1.285 +		glDisableVertexAttribArray(tattr);
   1.286 +#ifndef GL_ES
   1.287 +	} else {
   1.288 +		glDisableClientState(GL_TEXTURE_COORD_ARRAY);
   1.289 +#endif
   1.290 +	}
   1.291 +
   1.292 +#ifndef GL_ES
   1.293 +	glPopAttrib();
   1.294 +#else
   1.295 +	glDisable(GL_BLEND);
   1.296 +#endif
   1.297 +
   1.298 +	if(vbo) {
   1.299 +		glBindBuffer(GL_ARRAY_BUFFER, vbo);
   1.300 +	}
   1.301 +
   1.302 +	num_quads = 0;
   1.303 +}
   1.304 +
   1.305 +#endif	/* !def NO_OPENGL */