working test case

2 files changed, 39 insertions, 31 deletions

diff --git a/sys/libfont/font.c b/sys/libfont/font.c
index f7dfce7..ff54afd 100644
--- a/sys/libfont/font.c
+++ b/sys/libfont/font.c
@@ -2248,13 +2248,16 @@ sort_edges_quicksort(Edge *p, int n)
          /* handling of equality is crucial here */
          /* for sentinels & efficiency with duplicates */
          for (;;++i) {
-            if (!CMP_Y0(&p[i], &p[0])) break;
+            if (!CMP_Y0(&p[i], &p[0])) 
+                break;
          }
          for (;;--j) {
-            if (!CMP_Y0(&p[0], &p[j])) break;
+            if (!CMP_Y0(&p[0], &p[j])) 
+                break;
          }
          /* make sure we haven't crossed */
-         if (i >= j) break;
+         if (i >= j) 
+             break;
          t = p[i];
          p[i] = p[j];
          p[j] = t;
@@ -2284,7 +2287,7 @@ sort_edges(Edge *p, int n)
 
 static 
 void 
-rasterize(font·Bitmap *result, Point *pts, int *wcount, int windings, float scale_x, float scale_y, float shift_x, float shift_y, int off_x, int off_y, int invert, void *userdata)
+rasterize_points(font·Bitmap *result, Point *pts, int *wcount, int windings, float scale_x, float scale_y, float shift_x, float shift_y, int off_x, int off_y, int invert, void *userdata)
 {
    float y_scale_inv = invert ? -scale_y : scale_y;
    Edge *e;
@@ -2326,7 +2329,6 @@ rasterize(font·Bitmap *result, Point *pts, int *wcount, int windings, float sca
    }
 
    // now sort the edges by their highest point (should snap to integer, and then by x)
-   //STBTT_sort(e, n, sizeof(e[0]), edge_compare);
    sort_edges(e, n);
 
    // now, traverse the scanlines and find the intersections on each scanline, use xor winding rule
@@ -2339,7 +2341,9 @@ static
 void 
 add_point(Point *points, int n, float x, float y)
 {
-   if (!points) return; // during first pass, it's unallocated
+   if (!points) 
+       return; // during first pass, it's unallocated
+
    points[n].x = x;
    points[n].y = y;
 }
@@ -2428,7 +2432,8 @@ flatten(font·Vertex *vertices, int num_verts, float objspace_flatness, int **co
          ++n;
 
    *num_contours = n;
-   if (n == 0) return 0;
+   if (n == 0) 
+       return 0;
 
    *contour_lengths = malloc(sizeof(**contour_lengths) * n);
 
@@ -2482,25 +2487,26 @@ flatten(font·Vertex *vertices, int num_verts, float objspace_flatness, int **co
       }
       (*contour_lengths)[n] = num_points - start;
    }
-
    return points;
+
 error:
    free(points);
    free(*contour_lengths);
-   *contour_lengths = 0;
-   *num_contours = 0;
+   *contour_lengths = nil;
+   *num_contours    = 0;
    return nil;
 }
 
-void 
-font·rasterize(font·Bitmap *result, float flatness_in_pixels, font·Vertex *vertices, int num_verts, float scale_x, float scale_y, float shift_x, float shift_y, int x_off, int y_off, int invert, void *userdata)
+static
+void
+rasterize(font·Bitmap *result, float flatness_in_pixels, font·Vertex *vertices, int num_verts, float scale_x, float scale_y, float shift_x, float shift_y, int x_off, int y_off, int invert, void *userdata)
 {
-   float scale            = scale_x > scale_y ? scale_y : scale_x;
+   float scale            = (scale_x > scale_y) ? scale_y : scale_x;
    int winding_count      = 0;
    int *winding_lengths   = nil;
    Point *windings = flatten(vertices, num_verts, flatness_in_pixels / scale, &winding_lengths, &winding_count, userdata);
    if (windings) {
-      rasterize(result, windings, winding_lengths, winding_count, scale_x, scale_y, shift_x, shift_y, x_off, y_off, invert, userdata);
+      rasterize_points(result, windings, winding_lengths, winding_count, scale_x, scale_y, shift_x, shift_y, x_off, y_off, invert, userdata);
       free(winding_lengths);
       free(windings);
    }
@@ -2546,7 +2552,7 @@ font·glyph_makebitmap_subpixel(font·Info *info, float scale_x, float scale_y,
       if (gbm.pixels) {
          gbm.stride = gbm.w;
 
-         font·rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0, iy0, 1, info->userdata);
+         rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0, iy0, 1, info->userdata);
       }
    }
    free(vertices);
@@ -2574,7 +2580,7 @@ font·glyph_fillbitmap_subpixel(font·Info *info, uchar *output, int out_w, int
    gbm.stride = out_stride;
 
    if (gbm.w && gbm.h)
-      font·rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0,iy0, 1, info->userdata);
+      rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0,iy0, 1, info->userdata);
 
    free(vertices);
 }
@@ -2624,7 +2630,7 @@ h_prefilter(uchar *pixels, int w, int h, int stride_in_bytes, unsigned int kerne
    uchar buffer[SAMPLE];
    int safe_w = w - kernel_width;
    int j;
-   memset(buffer, 0, SAMPLE); // suppress bogus warning from VS2013 -analyze
+   memset(buffer, 0, SAMPLE);
    for (j=0; j < h; ++j) {
       int i;
       unsigned int total;
diff --git a/sys/libfont/test.c b/sys/libfont/test.c
index b92a56f..569d7ad 100644
--- a/sys/libfont/test.c
+++ b/sys/libfont/test.c
@@ -15,11 +15,12 @@ int
 main()
 {
     int i, err;
-    float  scale;
+    float x, dx, scale;
     uchar *bitmap;
     font·Info *info;
     mmap·Reader fontfile;
-    int x, y, as, ds, lg, ax, lsb, off, kern, r[2], c0[2], c1[2];
+    int off, y, ascent, descent, baseln;
+    int adv, lsb, r0[2], r1[2];
 
     err = 0;
     fontfile = mmap·open("/home/nolln/root/data/DejaVuSans.ttf");
@@ -34,22 +35,23 @@ main()
     bitmap = calloc(W*H, sizeof(*bitmap)); 
     scale  = font·scaleheightto(info, L);
 
-    font·vmetrics(info, &as, &ds, &lg);
-    as *= scale;
-    ds *= scale;
+    font·vmetrics(info, &ascent, &descent, &baseln);
+    ascent *= scale;
 
-    x = 0;
+    x = 0.;
     for (i = 0; i < strlen(phrase); i++) {
-        font·code_hmetrics(info, phrase[i], &ax, &lsb);
-        font·code_bitmapbox(info, phrase[i], scale, scale, c0, c0+1, c1, c1+1);
+        dx = x - (float)floor(x);
+        font·code_hmetrics(info, phrase[i], &adv, &lsb);
+        font·code_bitmapbox_subpixel(info, phrase[i], scale, scale, dx, 0, r0, r0+1, r1, r1+1);
 
-        y   = as + c0[1];
-        off = x + lsb * scale + y * W; 
-        font·code_fillbitmap(info, bitmap+off, c1[0]-c0[0], c1[1]-c0[1], W, scale, scale, phrase[i]);
+        y   = ascent + r0[1];
+        off = (int)floor(x) + (lsb * scale) + y * W; 
 
-        x += ax * scale;
-        kern = font·code_kernadvance(info, phrase[i], phrase[i+1]);
-        x += kern * scale;
+        font·code_fillbitmap_subpixel(info, bitmap+off, r1[0]-r0[0], r1[1]-r0[1], W, scale, scale, dx, 0, phrase[i]);
+
+        x += scale * adv;
+        if (phrase[i+1])
+            x += scale * font·code_kernadvance(info, phrase[i], phrase[i+1]);
     }
 
     stbi_write_png("out.png", W, H, 1, bitmap, W);