eleni.mutantstargoat.com Git - winnie/blob - src/text.cc

   1 #include <ft2build.h>
   2 #include <freetype/freetype.h>
   3
   4 #include "gfx.h"
   5 #include "shalloc.h"
   6 #include "text.h"
   7
   8 #define DPI 72
   9 #define FONT_PATH "/usr/share/fonts/truetype/ttf-dejavu/DejaVuSansMono.ttf"
  10 #define FONT_SIZE 16
  11
  12 static int draw_glyph(Pixmap *pixmap, int x, int y, char c);
  13
  14 struct Text {
  15         FT_Library ft_lib;
  16         FT_Face ft_face;
  17         int text_x, text_y;
  18         int text_color[3];
  19 };
  20
  21 static Text *text;
  22
  23 bool init_text()
  24 {
  25         if(!(text = (Text*)sh_malloc(sizeof *text))) {
  26                 return false;
  27         }
  28
  29         if(FT_Init_FreeType(&text->ft_lib)) {
  30                 fprintf(stderr, "Failed to initialize the FreeType library!\n");
  31                 return false;
  32         }
  33
  34         if(FT_New_Face(text->ft_lib, FONT_PATH, 0, &text->ft_face)) {
  35                 fprintf(stderr, "Failed to load font: %s\n", FONT_PATH);
  36                 return false;
  37         }
  38
  39         if(FT_Set_Char_Size(text->ft_face, 0, FONT_SIZE * 64, DPI, DPI)) {
  40                 fprintf(stderr, "Failed to set font size\n");
  41                 return false;
  42         }
  43
  44         set_text_color(255, 255, 255);
  45
  46         return true;
  47 }
  48
  49 void destroy_text()
  50 {
  51         sh_free(text);
  52 }
  53
  54 void draw_text(const char *txt, Pixmap *pixmap)
  55 {
  56         if(!pixmap) {
  57                 pixmap = get_framebuffer_pixmap();
  58         }
  59
  60         while(*txt != 0) {
  61                 text->text_x += draw_glyph(pixmap, text->text_x, text->text_y, *txt);
  62                 txt++;
  63         }
  64 }
  65
  66 void set_text_position(int x, int y)
  67 {
  68         text->text_x = x;
  69         text->text_y = y;
  70
  71 }
  72
  73 void set_text_color(int r, int g, int b)
  74 {
  75         text->text_color[0] = r;
  76         text->text_color[1] = g;
  77         text->text_color[2] = b;
  78 }
  79
  80 static int draw_glyph(Pixmap *pixmap, int x, int y, char c)
  81 {
  82         if(FT_Load_Char(text->ft_face, c, FT_LOAD_RENDER)) {
  83                 return 0;
  84         }
  85
  86         x += text->ft_face->glyph->bitmap_left;
  87         y -= text->ft_face->glyph->bitmap_top;
  88
  89         FT_Bitmap *ft_bmp = &text->ft_face->glyph->bitmap;
  90         unsigned char *bmp_ptr = ft_bmp->buffer;
  91         unsigned char *pxm_ptr = pixmap->get_image() + (pixmap->get_width() * y + x) * 4;
  92
  93         Rect clipping_rect = get_clipping_rect();
  94
  95         for(int i=0; i<ft_bmp->rows; i++) {
  96                 int dest_y = i + y;
  97                 if(dest_y >= clipping_rect.y + clipping_rect.height) {
  98                         break;
  99                 }
 100
 101                 if(dest_y >= clipping_rect.y) {
 102                         for(int j=0; j<ft_bmp->width; j++) {
 103                                 int dest_x = j + x;
 104
 105                                 if(dest_x >= clipping_rect.x + clipping_rect.width) {
 106                                         break;
 107                                 }
 108
 109                                 if(bmp_ptr[j] && dest_x >= clipping_rect.x) {
 110                                         int a = (int)bmp_ptr[j];
 111                                         pxm_ptr[4 * j] = (a * text->text_color[0] + pxm_ptr[4 * j] * (255 - a)) / 255;
 112                                         pxm_ptr[4 * j + 1] = (a * text->text_color[1] + pxm_ptr[4 * j + 1] * (255 - a)) / 255;
 113                                         pxm_ptr[4 * j + 2] = (a * text->text_color[2] + pxm_ptr[4 * j + 2] * (255 - a)) / 255;
 114                                 }
 115                         }
 116                 }
 117
 118                 pxm_ptr += 4 * pixmap->get_width();
 119                 bmp_ptr += ft_bmp->pitch;
 120         }
 121
 122         return text->ft_face->glyph->advance.x >> 6;
 123 }