Re: [ft-devel] Points in FT_Outline

[Wenlin Institute]

If you insert something like

        FT_Set_Pixel_Sizes(face, 0, 12);

before FT_Get_Char_Index, then the coordinates won't all be the same.

-Tom Bishop

On Dec 11, 2007, at 9:11 AM, Jjgod Jiang wrote:

> Hi,
>
> I'm trying to fetch all the points from FT_Outline of a glyph, here is
> a minimal example,
>
>     /* testft.c: test FreeType capabilities */
>
>     #include <stdio.h>
>     #include <stdlib.h>
>     #include <assert.h>
>     #include <ft2build.h>
>     #include FT_FREETYPE_H
>     #include FT_OUTLINE_H
>
>     #define DOUBLE_TO_16_16(d) ((FT_Fixed)((d) * 65536.0))
>     #define DOUBLE_FROM_26_6(t) ((double)(t) / 64.0)
>
>     int move_to(const FT_Vector *to, void *user);
>     int line_to(const FT_Vector *to, void *user);
>     int conic_to(const FT_Vector *control, const FT_Vector *to,  
> void *user);
>     int cubic_to(const FT_Vector *control1, const FT_Vector *control2,
>                  const FT_Vector *to, void *user);
>
>     int main(int argc, char *argv[])
>     {
>         FT_Error    error;
>         FT_Library  library;
>         FT_Face     face;
>         FT_UInt     glyph_index;
>         FT_Outline *outline;
>         FT_ULong    charcode = 'Z';
>
>         error = FT_Init_FreeType(&library);
>         assert(error == 0);
>
>         error = FT_New_Face(library, argv[1], 0, &face);
>         assert(error == 0);
>
>         glyph_index = FT_Get_Char_Index(face, charcode);
>         assert(glyph_index != 0);
>
>         error = FT_Load_Glyph(face, glyph_index,
>                               FT_LOAD_DEFAULT);
>         assert(error == 0);
>
>         assert(face->glyph->format == FT_GLYPH_FORMAT_OUTLINE);
>
>         outline = &face->glyph->outline;
>         printf("n_contours = %d\n", outline->n_contours);
>         printf("n_points   = %d\n", outline->n_points);
>
>         FT_Outline_Funcs outline_funcs = { move_to, line_to, conic_to,
> cubic_to, 0, 0 };
>         FT_Outline_Decompose(outline, &outline_funcs, NULL);
>
>         FT_Done_Face(face);
>         FT_Done_FreeType(library);
>
>         return 0;
>     }
>
>     void print4bytes(const char *bytes)
>     {
>         int i;
>
>         for (i = 0; i < 4; i++)
>             printf("%02X ", bytes[i]);
>
>         printf("\n");
>     }
>
>     int move_to(const FT_Vector *to, void *user)
>     {
>         print4bytes((char *) &(to->x));
>         print4bytes((char *) &(to->y));
>
>         printf("move_to([%g, %g])\n",
>                 DOUBLE_FROM_26_6(to->x), DOUBLE_FROM_26_6(to->y));
>
>         return 0;
>     }
>
>     int line_to(const FT_Vector *to, void *user)
>     {
>         printf("line_to([%g, %g])\n",
>                DOUBLE_FROM_26_6(to->x), DOUBLE_FROM_26_6(to->y));
>
>         return 0;
>     }
>
>     int conic_to(const FT_Vector *control, const FT_Vector *to,  
> void *user)
>     {
>         printf("conic_to(c = [%g, %g], to = [%g, %g])\n",
>                DOUBLE_FROM_26_6(control->x), DOUBLE_FROM_26_6 
> (control->y),
>                DOUBLE_FROM_26_6(to->x), DOUBLE_FROM_26_6(to->y));
>
>         return 0;
>     }
>
>     int cubic_to(const FT_Vector *control1, const FT_Vector *control2,
>                  const FT_Vector *to, void *user)
>     {
>         printf("cubic_to(c1 = [%g, %g], c2 = [%g, %g], to = [%g, % 
> g])\n",
>                DOUBLE_FROM_26_6(control1->x), DOUBLE_FROM_26_6 
> (control1->y),
>                DOUBLE_FROM_26_6(control2->x), DOUBLE_FROM_26_6 
> (control2->y),
>                DOUBLE_FROM_26_6(to->x), DOUBLE_FROM_26_6(to->y));
>         return 0;
>     }
>
> The n_points and n_contours printed is correct, but the point  
> FT_Vector
> does not contain any useful values, for example:
>
> $ ./testft /Library/Fonts/Arial.ttf
> n_contours = 1
> n_points   = 13
> 00 00 00 00
> 04 00 00 00
> move_to([0, 0.0625])
> line_to([0, 0.0625])
> line_to([0, 0.0625])
> conic_to(c = [0, 0.0625], to = [0, 0.0625])
> line_to([0, 0.0625])
> line_to([0, 0.0625])
> line_to([0, 0.0625])
> line_to([0, 0.0625])
> line_to([0, 0.0625])
> line_to([0, 0.0625])
> line_to([0, 0.0625])
> line_to([0, 0.0625])
> line_to([0, 0.0625])
>
> I'm wondering what's wrong with my code. Thanks!
>
> - Jiang
>
>
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> http://lists.nongnu.org/mailman/listinfo/freetype-devel


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