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-rw-r--r--rtgrpblib_draw_quadratic_bezier.c206
1 files changed, 194 insertions, 12 deletions
diff --git a/rtgrpblib_draw_quadratic_bezier.c b/rtgrpblib_draw_quadratic_bezier.c
index 8aae11e..e2202c6 100644
--- a/rtgrpblib_draw_quadratic_bezier.c
+++ b/rtgrpblib_draw_quadratic_bezier.c
@@ -90,23 +90,22 @@ rtgrpblib_draw_quadratic_bezier(RASTER *restrict raster, double x1, double y1,
size_t nts = 0;
size_t i;
-#ifdef TODO /* untested */
/* Can we downgrade the curve to a linear Bézier curve?
*
* (y2 - y1)/(x2 - x1) = (y3 - y2)/(x3 - x2) = (y3 - y1)/(x3 - x1)
* (y2 - y1)/(x2 - x1) = (y3 - y2)/(x3 - x2)
* (y2 - y1)(x3 - x2) = (y3 - y2)(x2 - x1)
*/
- if ((y3 - y1) * (x3 - x2) == (y3 - y2) * (x2 - x1)) {
- if (x1 <= x2 && x2 <= x3 && y1 <= y2 && y2 <= y3)
- rtgrpblib_draw_linear_bezier(raster, x1, y1, x3, y3);
- else if (x1 <= x3 && x3 <= x2 && y1 <= y3 && y3 <= y2)
- rtgrpblib_draw_linear_bezier(raster, x1, y1, x2, y2);
- else
- rtgrpblib_draw_linear_bezier(raster, x2, y2, x3, y3);
+ if ((y2 - y1) * (x3 - x2) == (y3 - y2) * (x2 - x1)) {
+ /* Drawing (x1, y1)--(x2, y2) plus (x2, y2)--(x3, y3)
+ * is equivalent to drawing (x1, y1)--(x3, y3) because
+ * the result is signed and if (x2, y2) is outside the
+ * (x1, y1)--(x3, y3) line (x2, y2)--(x3, y3) erases
+ * the part that (x1, y1)--(x2, y2) extends to
+ * (x1, y1)--(x3, y3) */
+ rtgrpblib_draw_linear_bezier(raster, x1, y1, x3, y3);
return;
}
-#endif
/* Beginning and end of curve */
ts[nts++] = 0.0;
@@ -126,12 +125,12 @@ rtgrpblib_draw_quadratic_bezier(RASTER *restrict raster, double x1, double y1,
/* Remove any segments above or below the raster */
y = evaluate_quadratic_bezier(t, y1, y2, y3);
- if (y < 0 || y >= (double)raster->height)
+ if (y < 0 || y > (double)raster->height)
continue;
/* If the segment is inside the raster, draw it, */
x = evaluate_quadratic_bezier(t, x1, x2, x3);
- if (0 <= x && x < (double)raster->width) {
+ if (0 <= x && x <= (double)raster->width) {
draw_bounded_quadratic_bezier(raster, x1, y1, x2, y2, x3, y3, t1, t2);
continue;
}
@@ -157,10 +156,193 @@ rtgrpblib_draw_quadratic_bezier(RASTER *restrict raster, double x1, double y1,
#else
+static RASTER *raster;
+static RASTER *refraster;
+
+
+static double
+frand(double a, double b)
+{
+ int i = rand();
+ double f = (double)i / (double)RAND_MAX;
+ double max = fmax(a, b);
+ double min = fmin(a, b);
+ return fma(f, max - min, min);
+}
+
+
+static void
+check_line(double x1, double y1, double x2, double y2, double x3, double y3, int exact)
+{
+ size_t i;
+
+ alarm(5);
+ rtgrpblib_draw_quadratic_bezier(raster, x1, y1, x2, y2, x3, y3);
+
+ alarm(5);
+ rtgrpblib_draw_linear_bezier(refraster, x1, y1, x3, y3);
+
+ alarm(0);
+
+ if (exact) {
+ ASSERT(!memcmp(raster->cells, refraster->cells, 100 * sizeof(*raster->cells)));
+ } else {
+ for (i = 0; i < 100; i++) {
+ if (!eq(raster->cells[i].cell_coverage, refraster->cells[i].cell_coverage))
+ fprintf(stderr, "c%02zu: %la ref: %la; diff: %lg=%la (tol: %la)\n", i, raster->cells[i].cell_coverage, refraster->cells[i].cell_coverage, refraster->cells[i].cell_coverage - raster->cells[i].cell_coverage, refraster->cells[i].cell_coverage - raster->cells[i].cell_coverage, TOLERANCE);
+ if (!eq(raster->cells[i].opposite_coverage, refraster->cells[i].opposite_coverage))
+ fprintf(stderr, "o%02zu: %la ref: %la; diff: %lg=%la (tol: %la)\n", i, raster->cells[i].opposite_coverage, refraster->cells[i].opposite_coverage, raster->cells[i].opposite_coverage - refraster->cells[i].opposite_coverage, raster->cells[i].opposite_coverage - refraster->cells[i].opposite_coverage, TOLERANCE);
+ }
+ for (i = 0; i < 100; i++) {
+ if (!eq(raster->cells[i].cell_coverage, refraster->cells[i].cell_coverage) ||
+ !eq(raster->cells[i].opposite_coverage, refraster->cells[i].opposite_coverage)) {
+ print_raster(refraster);
+ print_raster(raster);
+ }
+ ASSERT(eq(raster->cells[i].cell_coverage, refraster->cells[i].cell_coverage));
+ ASSERT(eq(raster->cells[i].opposite_coverage, refraster->cells[i].opposite_coverage));
+ }
+ }
+ rtgrpblib_reset_raster(raster, 10, 10);
+ rtgrpblib_reset_raster(refraster, 10, 10);
+}
+
+
+static void
+check_simple_lines(void)
+{
+ check_line(1, 1, 2, 2, 3, 3, 1);
+ check_line(1, 1, 3, 3, 2, 2, 1);
+ check_line(2, 2, 1, 1, 3, 3, 1);
+ check_line(2, 2, 3, 3, 1, 1, 1);
+ check_line(3, 3, 1, 1, 2, 2, 1);
+ check_line(3, 3, 2, 2, 1, 1, 1);
+ check_line(1, 1, 3, 3, 3, 3, 1);
+ check_line(1, 1, 1, 1, 3, 3, 1);
+
+ check_line(1, 4, 2, 4, 3, 4, 1);
+ check_line(1, 4, 3, 4, 2, 4, 1);
+ check_line(2, 4, 1, 4, 3, 4, 1);
+ check_line(2, 4, 3, 4, 1, 4, 1);
+ check_line(3, 4, 1, 4, 2, 4, 1);
+ check_line(3, 4, 2, 4, 1, 4, 1);
+ check_line(1, 4, 3, 4, 3, 4, 1);
+ check_line(1, 4, 1, 4, 3, 4, 1);
+
+ check_line(4, 1, 4, 2, 4, 3, 1);
+ check_line(4, 1, 4, 3, 4, 2, 1);
+ check_line(4, 2, 4, 1, 4, 3, 1);
+ check_line(4, 2, 4, 3, 4, 1, 1);
+ check_line(4, 3, 4, 1, 4, 2, 1);
+ check_line(4, 3, 4, 2, 4, 1, 1);
+ check_line(4, 1, 4, 3, 4, 3, 1);
+ check_line(4, 1, 4, 1, 4, 3, 1);
+}
+
+
+static void
+check_random_bounded_lines(int exact)
+{
+ double x1, x2, x3;
+ double y1, y2, y3;
+ double mid;
+ size_t i;
+
+ for (i = 0; i < 100000UL; i++) {
+ x1 = floor(frand(0, 11));
+ y1 = floor(frand(0, 11));
+ x3 = floor(frand(0, 11));
+ y3 = floor(frand(0, 11));
+ x1 -= (double)(x1 > 10);
+ x2 -= (double)(x2 > 10);
+ y1 -= (double)(y1 > 10);
+ y2 -= (double)(y2 > 10);
+ mid = frand(0, 1);
+
+ if (x3 - x1) {
+ x2 = floor(mid * (x3 - x1) + x1);
+ y2 = y1 + (x2 - x1) * (y3 - y1) / (x3 - x1);
+ } else if (y3 - y1) {
+ x2 = x1;
+ y2 = floor(mid * (y3 - y1) + y1);
+ } else {
+ x2 = x1;
+ y2 = y1;
+ }
+
+ if (!exact)
+ check_line(x1, y1, x2, y2, x3, y3, x2 == floor(x2) && y2 == floor(y2));
+ else if (x2 == floor(x2) && y2 == floor(y2))
+ check_line(x1, y1, x2, y2, x3, y3, 1);
+ }
+}
+
+
+static void
+check_random_unbounded_lines(int exact)
+{
+ double x1, x2, x3;
+ double y1, y2, y3;
+ double mid;
+ size_t i;
+
+ for (i = 0; i < 100000UL; i++) {
+ x1 = floor(frand(-5, 15));
+ y1 = floor(frand(-5, 15));
+ x3 = floor(frand(-5, 15));
+ y3 = floor(frand(-5, 15));
+ mid = frand(-2, 2);
+
+ if (x3 - x1) {
+ x2 = floor(mid * (x3 - x1) + x1);
+ y2 = y1 + (x2 - x1) * (y3 - y1) / (x3 - x1);
+ } else if (y3 - y1) {
+ x2 = x1;
+ y2 = floor(mid * (y3 - y1) + y1);
+ } else {
+ x2 = x1;
+ y2 = y1;
+ }
+
+ if (!exact)
+ check_line(x1, y1, x2, y2, x3, y3, x2 == floor(x2) && y2 == floor(y2));
+ else if (x2 == floor(x2) && y2 == floor(y2))
+ check_line(x1, y1, x2, y2, x3, y3, 1);
+ }
+}
+
+
int
main(void)
{
- return 0; /* TODO add test */
+ raster = rtgrpblib_create_raster(10, 10);
+ ASSERT(raster);
+ refraster = rtgrpblib_create_raster(10, 10);
+ ASSERT(refraster);
+ srand((unsigned)(uintptr_t)raster);
+
+ check_simple_lines();
+ check_random_bounded_lines(1);
+ check_random_unbounded_lines(1);
+ //TODO check_random_bounded_lines(0);
+ //TODO check_random_unbounded_lines(0);
+ raster->draftness = -1;
+ refraster->draftness = -1;
+ check_simple_lines();
+ check_random_bounded_lines(1);
+ check_random_unbounded_lines(1);
+#ifdef TODO_NOT_IMPLEMENTED
+ check_random_bounded_lines(0);
+ check_random_unbounded_lines(0);
+#endif
+ raster->draftness = 0.5;
+ refraster->draftness = 0.5;
+
+ /* TODO add tests */
+
+ free(raster);
+ free(refraster);
+ return 0;
}
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