FreeTypeGL-0.0.1: src/demo/demo-outline.c
/* =========================================================================
* Freetype GL - A C OpenGL Freetype engine
* Platform: Any
* WWW: http://code.google.com/p/freetype-gl/
* -------------------------------------------------------------------------
* Copyright 2011,2012 Nicolas P. Rougier. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY NICOLAS P. ROUGIER ''AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL NICOLAS P. ROUGIER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* The views and conclusions contained in the software and documentation are
* those of the authors and should not be interpreted as representing official
* policies, either expressed or implied, of Nicolas P. Rougier.
* ========================================================================= */
#include <stdarg.h>
#include "freetype-gl.h"
#include "vertex-buffer.h"
#include "markup.h"
// ------------------------------------------------------- typedef & struct ---
typedef struct {
float x, y, z;
float u, v;
float r, g, b, a;
} vertex_t;
// ------------------------------------------------------- global variables ---
texture_atlas_t * atlas;
vertex_buffer_t * buffer;
// ---------------------------------------------------------------- display ---
void display( void )
{
glClearColor( 0.40, 0.40, 0.45, 1.00 );
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
glEnable( GL_BLEND );
glEnable( GL_TEXTURE_2D );
glEnable( GL_COLOR_MATERIAL );
glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );
glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
vertex_buffer_render( buffer, GL_TRIANGLES, "vtc" );
glutSwapBuffers( );
}
// ---------------------------------------------------------------- reshape ---
void reshape(int width, int height)
{
glViewport(0, 0, width, height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0, width, 0, height, -1, 1);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glutPostRedisplay();
}
// --------------------------------------------------------------- keyboard ---
void keyboard( unsigned char key, int x, int y )
{
if ( key == 27 )
{
exit( EXIT_SUCCESS );
}
}
// --------------------------------------------------------------- add_text ---
void add_text( vertex_buffer_t * buffer, vec2 * pen, ... )
{
markup_t *markup;
wchar_t *text;
va_list args;
va_start ( args, pen );
do {
markup = va_arg( args, markup_t * );
if( markup == NULL )
{
break;
}
text = va_arg( args, wchar_t * );
size_t i;
texture_font_t * font = markup->font;
float r = markup->foreground_color.red;
float g = markup->foreground_color.green;
float b = markup->foreground_color.blue;
float a = markup->foreground_color.alpha;
for( i=0; i<wcslen(text); ++i )
{
texture_glyph_t *glyph = texture_font_get_glyph( font, text[i] );
if( glyph != NULL )
{
float kerning = 0;
if( i > 0)
{
kerning = texture_font_glyph_get_kerning( font, glyph, text[i-1] );
}
pen->x += kerning;
/* Actual glyph */
float x0 = ( pen->x + glyph->offset_x );
float y0 = (int)( pen->y + glyph->offset_y );
float x1 = ( x0 + glyph->width );
float y1 = (int)( y0 - glyph->height );
float s0 = glyph->s0;
float t0 = glyph->t0;
float s1 = glyph->s1;
float t1 = glyph->t1;
GLuint index = buffer->vertices->size;
GLuint indices[] = {index, index+1, index+2,
index, index+2, index+3};
vertex_t vertices[] = {
{ (int)x0,y0,0, s0,t0, r,g,b,a },
{ (int)x0,y1,0, s0,t1, r,g,b,a },
{ (int)x1,y1,0, s1,t1, r,g,b,a },
{ (int)x1,y0,0, s1,t0, r,g,b,a } };
vertex_buffer_push_back_indices( buffer, indices, 6 );
vertex_buffer_push_back_vertices( buffer, vertices, 4 );
pen->x += glyph->advance_x;
}
}
} while( markup != 0 );
va_end ( args );
}
// ------------------------------------------------------------------- main ---
int main( int argc, char **argv )
{
size_t i;
size_t width = 600, height = 250;
glutInit( &argc, argv );
glutInitWindowSize( width, height );
glutInitDisplayMode( GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH );
glutCreateWindow( "Glyph Outline" );
glutReshapeFunc( reshape );
glutDisplayFunc( display );
glutKeyboardFunc( keyboard );
atlas = texture_atlas_new( 512, 512, 1 );
buffer = vertex_buffer_new( "v3f:t2f:c4f" );
vec4 white = {{1.0, 1.0, 1.0, 1.0}};
vec4 none = {{1.0, 1.0, 1.0, 0.0}};
markup_t markup = {
.family = "fonts/Vera.ttf",
.size = 80,
.bold = 0,
.italic = 0,
.rise = 0.0,
.spacing = 0.0,
.gamma = 1.5,
.foreground_color = white,
.background_color = none,
.underline = 0,
.underline_color = white,
.overline = 0,
.overline_color = white,
.strikethrough = 0,
.strikethrough_color = white,
.font = 0,
};
markup.font = texture_font_new( atlas, "fonts/Vera.ttf", markup.size );
markup.font->outline_type = 1;
vec2 pen;
pen.x = 40;
pen.y = 190;
for( i=0; i< 10; ++i)
{
markup.font->outline_thickness = 2*((i+1)/10.0);
add_text( buffer, &pen, &markup, L"g", NULL );
}
pen.x = 40;
pen.y = 110;
markup.font->outline_type = 2;
for( i=0; i< 10; ++i)
{
markup.font->outline_thickness = 2*((i+1)/10.0);
add_text( buffer, &pen, &markup, L"g", NULL );
}
pen.x = 40;
pen.y = 30;
markup.font->outline_type = 3;
for( i=0; i< 10; ++i)
{
markup.font->outline_thickness = 1*((i+1)/10.0);
add_text( buffer, &pen, &markup, L"g", NULL );
}
glutMainLoop( );
return 0;
}