altos/draw: Add transforms to polygon code

[fw/altos] / src / draw / ao_line.c

diff --git a/src/draw/ao_line.c b/src/draw/ao_line.c
index 318f101e05b4edaadb93891bfdb9f69174d1248f..c6b49ee0d6cb1fd71ffe83f3b1369cedeeb15896 100644 (file)
--- a/src/draw/ao_line.c
+++ b/src/draw/ao_line.c
@@ -142,12 +142,12 @@ struct ao_cbox {
 /* -b <= a, so we need to make a bigger */
 static int16_t
 div_ceil(int32_t a, int16_t b) {
-       return (a + b + b - 1) / b - 1;
+       return (int16_t) ((a + b + b - 1) / b - 1);
 }
 
 static int16_t
 div_floor_plus_one(int32_t a, int16_t b) {
-       return (a + b) / b;
+       return (int16_t) ((a + b) / b);
 }
 
 static int8_t
@@ -202,10 +202,10 @@ ao_clip_line(struct ao_cc *c, struct ao_cbox *b)
                adjust_minor = adj_min;
        }
 
-       c->e += adjust_major * c->e1 + adjust_minor * c->e3;
+       c->e = (int16_t) (c->e + adjust_major * c->e1 + adjust_minor * c->e3);
 
-       c->major += c->sign_major * adjust_major;
-       c->minor += c->sign_minor * adjust_minor;
+       c->major = (int16_t) (c->major + c->sign_major * adjust_major);
+       c->minor = (int16_t) (c->minor + c->sign_minor * adjust_minor);
 
        return true;
 }
@@ -239,7 +239,7 @@ ao_line(const struct ao_bitmap      *dst,
        if (adx > ady) {
                axis = X_AXIS;
                e1 = ady << 1;
-               e2 = e1 - (adx << 1);
+               e2 = e1 - (int16_t) (adx << 1);
                e = e1 - adx;
 
                clip_1.major = x1;
@@ -256,7 +256,7 @@ ao_line(const struct ao_bitmap      *dst,
        } else {
                axis = Y_AXIS;
                e1 = adx << 1;
-               e2 = e1 - (ady << 1);
+               e2 = e1 - (int16_t) (ady << 1);
                e = e1 - ady;
 
                clip_1.major = y1;
@@ -289,7 +289,7 @@ ao_line(const struct ao_bitmap      *dst,
        if (!ao_clip_line(&clip_2, &cbox))
                return;
 
-       len = clip_1.sign_major * (clip_2.major - clip_1.major) + clip_2.first;
+       len = (int16_t) (clip_1.sign_major * (clip_2.major - clip_1.major) + clip_2.first);
 
        if (len <= 0)
                return;