/* Freetype GL - A C OpenGL Freetype engine * * Distributed under the OSI-approved BSD 2-Clause License. See accompanying * file `LICENSE` for more details. */ #include #include #include #include "freetype-gl.h" #include "vertex-buffer.h" #include "text-buffer.h" #include "markup.h" #include "shader.h" #include "mat4.h" #include "screenshot-util.h" #include #ifndef max #define max(a,b) ((a) > (b) ? (a) : (b)) #endif #ifndef min #define min(a,b) ((a) < (b) ? (a) : (b)) #endif double total_time = 0.0; // ------------------------------------------------------- typedef & struct --- typedef struct { float x, y, z; // position float s, t; // texture float r, g, b, a; // color } vertex_t; // ------------------------------------------------------- global variables --- GLuint shader; vertex_buffer_t *buffer; texture_atlas_t *atlas; mat4 model, view, projection; // --------------------------------------------------------------- add_text --- vec4 add_text( vertex_buffer_t * buffer, texture_font_t * font, char *text, vec4 * color, vec2 * pen ) { vec4 bbox = {{0,0,0,0}}; size_t i; float r = color->red, g = color->green, b = color->blue, a = color->alpha; for( i = 0; i < strlen(text); ++i ) { glfwSetTime(total_time); texture_glyph_t *glyph = texture_font_get_glyph( font, text + i ); total_time += glfwGetTime(); if( glyph != NULL ) { float kerning = 0.0f; if( i > 0) { kerning = texture_glyph_get_kerning( glyph, text + i - 1 ); } pen->x += kerning; int x0 = (int)( pen->x + glyph->offset_x ); int y0 = (int)( pen->y + glyph->offset_y ); int x1 = (int)( x0 + glyph->width ); int y1 = (int)( y0 - glyph->height ); float s0 = glyph->s0; float t0 = glyph->t0; float s1 = glyph->s1; float t1 = glyph->t1; GLuint indices[6] = {0,1,2, 0,2,3}; vertex_t vertices[4] = { { x0,y0,0, s0,t0, r,g,b,a }, { x0,y1,0, s0,t1, r,g,b,a }, { x1,y1,0, s1,t1, r,g,b,a }, { x1,y0,0, s1,t0, r,g,b,a } }; vertex_buffer_push_back( buffer, vertices, 4, indices, 6 ); pen->x += glyph->advance_x; if (x0 < bbox.x) bbox.x = x0; if (y1 < bbox.y) bbox.y = y1; if ((x1 - bbox.x) > bbox.width) bbox.width = x1-bbox.x; if ((y0 - bbox.y) > bbox.height) bbox.height = y0-bbox.y; } } return bbox; } // ------------------------------------------------------------------- init --- void init( void ) { texture_font_t *font = 0; atlas = texture_atlas_new( 512, 512, 1 ); const char * filename = "fonts/Vera.ttf"; char *text = "A Quick Brown Fox Jumps Over The Lazy Dog 0123456789"; buffer = vertex_buffer_new( "vertex:3f,tex_coord:2f,color:4f" ); vec2 pen = {{0,0}}; vec4 black = {{1,1,1,1}}; font = texture_font_new_from_file( atlas, 48, filename ); font->rendermode = RENDER_SIGNED_DISTANCE_FIELD; vec4 bbox = add_text( buffer, font, text, &black, &pen ); size_t i; vector_t * vertices = buffer->vertices; for( i=0; i< vector_size(vertices); ++i ) { vertex_t * vertex = (vertex_t *) vector_get(vertices,i); vertex->x -= (int)(bbox.x + bbox.width/2); vertex->y -= (int)(bbox.y + bbox.height/2); } glGenTextures( 1, &atlas->id ); glBindTexture( GL_TEXTURE_2D, atlas->id ); glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE ); glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE ); glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR ); glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR ); glTexImage2D( GL_TEXTURE_2D, 0, GL_RED, atlas->width, atlas->height, 0, GL_RED, GL_UNSIGNED_BYTE, atlas->data ); shader = shader_load( "shaders/distance-field.vert", "shaders/distance-field-2.frag" ); mat4_set_identity( &projection ); mat4_set_identity( &model ); mat4_set_identity( &view ); } // ---------------------------------------------------------------- display --- void display( GLFWwindow* window ) { glClearColor( 1, 1, 1, 1 ); glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); glEnable( GL_BLEND ); glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA ); GLint viewport[4]; glGetIntegerv( GL_VIEWPORT, viewport ); GLint width = viewport[2]; GLint height = viewport[3]; srand(4); vec4 color = {{0.067,0.333, 0.486, 1.0}}; size_t i; for( i=0; i<40; ++i) { float scale = .25 + 4.75 * pow(rand()/(float)(RAND_MAX),2); float angle = 90*(rand()%2); float x = (.05 + .9*(rand()/(float)(RAND_MAX)))*width; float y = (-.05 + .9*(rand()/(float)(RAND_MAX)))*height; float a = 0.1+.8*(pow((1.0-scale/5),2)); mat4_set_identity( &model ); mat4_rotate( &model, angle,0,0,1); mat4_scale( &model, scale, scale, 1); mat4_translate( &model, x, y, 0); glUseProgram( shader ); { glUniform1i( glGetUniformLocation( shader, "u_texture" ), 0 ); glUniform4f( glGetUniformLocation( shader, "u_color" ), color.r, color.g, color.b, a); glUniformMatrix4fv( glGetUniformLocation( shader, "u_model" ), 1, 0, model.data); glUniformMatrix4fv( glGetUniformLocation( shader, "u_view" ), 1, 0, view.data); glUniformMatrix4fv( glGetUniformLocation( shader, "u_projection" ), 1, 0, projection.data); vertex_buffer_render( buffer, GL_TRIANGLES ); } } glfwSwapBuffers( window ); } // ---------------------------------------------------------------- reshape --- void reshape( GLFWwindow* window, int width, int height ) { glViewport(0, 0, width, height); mat4_set_orthographic( &projection, 0, width, 0, height, -1, 1); } // --------------------------------------------------------------- keyboard --- void keyboard( GLFWwindow* window, int key, int scancode, int action, int mods ) { if ( key == GLFW_KEY_ESCAPE && action == GLFW_PRESS ) { glfwSetWindowShouldClose( window, GL_TRUE ); } } // --------------------------------------------------------- error-callback --- void error_callback( int error, const char* description ) { fputs( description, stderr ); } // ------------------------------------------------------------------- main --- int main( int argc, char **argv ) { GLFWwindow* window; char* screenshot_path = NULL; if (argc > 1) { if (argc == 3 && 0 == strcmp( "--screenshot", argv[1] )) screenshot_path = argv[2]; else { fprintf( stderr, "Unknown or incomplete parameters given\n" ); exit( EXIT_FAILURE ); } } glfwSetErrorCallback( error_callback ); if (!glfwInit( )) { exit( EXIT_FAILURE ); } glfwWindowHint( GLFW_VISIBLE, GL_FALSE ); glfwWindowHint( GLFW_RESIZABLE, GL_FALSE ); window = glfwCreateWindow( 800, 600, argv[0], NULL, NULL ); if (!window) { glfwTerminate( ); exit( EXIT_FAILURE ); } glfwMakeContextCurrent( window ); glfwSwapInterval( 1 ); glfwSetFramebufferSizeCallback( window, reshape ); glfwSetWindowRefreshCallback( window, display ); glfwSetKeyCallback( window, keyboard ); #ifndef __APPLE__ glewExperimental = GL_TRUE; GLenum err = glewInit(); if (GLEW_OK != err) { /* Problem: glewInit failed, something is seriously wrong. */ fprintf( stderr, "Error: %s\n", glewGetErrorString(err) ); exit( EXIT_FAILURE ); } fprintf( stderr, "Using GLEW %s\n", glewGetString(GLEW_VERSION) ); #endif init(); fprintf(stderr, "Total time to generate distance map: %fs\n", total_time); glfwShowWindow( window ); { int pixWidth, pixHeight; glfwGetFramebufferSize( window, &pixWidth, &pixHeight ); reshape( window, pixWidth, pixHeight ); } glfwSetTime(0.0); while (!glfwWindowShouldClose( window )) { display( window ); glfwPollEvents( ); if (screenshot_path) { screenshot( window, screenshot_path ); glfwSetWindowShouldClose( window, 1 ); } } glDeleteTextures( 1, &atlas->id ); atlas->id = 0; texture_atlas_delete( atlas ); glfwDestroyWindow( window ); glfwTerminate( ); return EXIT_SUCCESS; }