diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 5b49deba25..e6919f8e71 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -23,6 +23,7 @@ add_subdirectory(saveload)
add_subdirectory(sound)
add_subdirectory(spriteloader)
add_subdirectory(table)
+add_subdirectory(tests)
add_subdirectory(video)
add_subdirectory(widgets)
diff --git a/src/landscape.cpp b/src/landscape.cpp
index bfff296294..aeacf65ba7 100644
--- a/src/landscape.cpp
+++ b/src/landscape.cpp
@@ -221,7 +221,7 @@ uint ApplyFoundationToSlope(Foundation f, Slope *s)
* @param corners slope to examine
* @return height of given point of given slope
*/
-uint GetPartialPixelZ(int x, int y, Slope corners)
+static constexpr uint InternalGetPartialPixelZ(int x, int y, Slope corners)
{
if (IsHalftileSlope(corners)) {
/* A foundation is placed on half the tile at a specific corner. This means that,
@@ -285,6 +285,21 @@ uint GetPartialPixelZ(int x, int y, Slope corners)
}
}
+#include "tests/landscape_partial_pixel_z.h"
+
+/**
+ * Determines height at given coordinate of a slope.
+ * See #InternalGetPartialPixelZ.
+ * @param x x coordinate (value from 0 to 15)
+ * @param y y coordinate (value from 0 to 15)
+ * @param corners slope to examine
+ * @return height of given point of given slope
+ */
+uint GetPartialPixelZ(int x, int y, Slope corners)
+{
+ return InternalGetPartialPixelZ(x, y, corners);
+}
+
/**
* Return world \c Z coordinate of a given point of a tile. Normally this is the
* Z of the ground/foundation at the given location, but in some cases the
diff --git a/src/tests/CMakeLists.txt b/src/tests/CMakeLists.txt
new file mode 100644
index 0000000000..d028125ae9
--- /dev/null
+++ b/src/tests/CMakeLists.txt
@@ -0,0 +1,3 @@
+add_files(
+ landscape_partial_pixel_z.h
+)
diff --git a/src/tests/landscape_partial_pixel_z.h b/src/tests/landscape_partial_pixel_z.h
new file mode 100644
index 0000000000..a825709392
--- /dev/null
+++ b/src/tests/landscape_partial_pixel_z.h
@@ -0,0 +1,552 @@
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
+ * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see .
+ */
+
+/** @file landscape_partial_pixel_z.h Tests for consistency/validity of the results of GetPartialPixelZ. */
+
+/**
+ * Check whether the addition of two slope's GetPartialPixelZ values results in
+ * the GetPartialPixelZ values of the expected slope.
+ * This iterates over all sub-pixel locations within a single tile.
+ * @param slope_expected The slope that is expected.
+ * @param slope_a The first slope of the addition.
+ * @param slope_b The second slope of the addition.
+ * @return True iff at all GetPartialPixelZ results are the same for each sub-tile position.
+ */
+constexpr bool CheckPartialPixelZSlopeAddition(Slope slope_expected, Slope slope_a, Slope slope_b)
+{
+ for (uint x = 0; x < TILE_SIZE; x++) {
+ for (uint y = 0; y < TILE_SIZE; y++) {
+ int z_a = InternalGetPartialPixelZ(x, y, slope_a);
+ int z_b = InternalGetPartialPixelZ(x, y, slope_b);
+ int z_result = InternalGetPartialPixelZ(x, y, slope_expected);
+ if (z_result != z_a + z_b) return false;
+ }
+ }
+ return true;
+}
+
+/* A one corner slope, plus the opposite three corner slope results in a flat but elevated slope. */
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_ELEVATED, SLOPE_N, SLOPE_WSE));
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_ELEVATED, SLOPE_E, SLOPE_NWS));
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_ELEVATED, SLOPE_S, SLOPE_ENW));
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_ELEVATED, SLOPE_W, SLOPE_SEN));
+
+/* Diagonal slopes with their opposite slope result in a flat but elevated slope. */
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_ELEVATED, SLOPE_NW, SLOPE_SE));
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_ELEVATED, SLOPE_SW, SLOPE_NE));
+
+/* Half tile slopes with their opposite half tile slope result in a flat but elevated slope. */
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_ELEVATED, HalftileSlope(SLOPE_N, CORNER_N), HalftileSlope(SLOPE_S, CORNER_S)));
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_ELEVATED, HalftileSlope(SLOPE_E, CORNER_E), HalftileSlope(SLOPE_W, CORNER_W)));
+
+/* Two opposite one corner slopes result in the two corner slope with opposite corners. */
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_NS, SLOPE_N, SLOPE_S));
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_EW, SLOPE_E, SLOPE_W));
+
+/* A steep slope is a one corner slope on top of a three corner slope. */
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_STEEP_N, SLOPE_N, SLOPE_ENW));
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_STEEP_E, SLOPE_E, SLOPE_SEN));
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_STEEP_S, SLOPE_S, SLOPE_WSE));
+static_assert(CheckPartialPixelZSlopeAddition(SLOPE_STEEP_W, SLOPE_W, SLOPE_NWS));
+
+/* A half tile steep slope is a one corner half tile on top of a three corner slope. */
+static_assert(CheckPartialPixelZSlopeAddition(HalftileSlope(SLOPE_STEEP_N, CORNER_N), HalftileSlope(SLOPE_N, CORNER_N), SLOPE_ENW));
+static_assert(CheckPartialPixelZSlopeAddition(HalftileSlope(SLOPE_STEEP_E, CORNER_E), HalftileSlope(SLOPE_E, CORNER_E), SLOPE_SEN));
+static_assert(CheckPartialPixelZSlopeAddition(HalftileSlope(SLOPE_STEEP_S, CORNER_S), HalftileSlope(SLOPE_S, CORNER_S), SLOPE_WSE));
+static_assert(CheckPartialPixelZSlopeAddition(HalftileSlope(SLOPE_STEEP_W, CORNER_W), HalftileSlope(SLOPE_W, CORNER_W), SLOPE_NWS));
+
+
+/**
+ * Check whether the partial pixel Z values are the expected values. The arrays
+ * are as if the map is rotated 45 degrees counterclockwise.
+ * @param slope The slope that is to be checked.
+ * @param expected The expect partial pixels Z values.
+ * @return True iff at all GetPartialPixelZ results are the same as the expected Z-coordinates.
+ */
+constexpr bool CheckPartialPixelZ(Slope slope, std::array expected)
+{
+ for (uint i = 0; i < expected.size(); i++) {
+ int actual = InternalGetPartialPixelZ(GB(i, 4, 4), GB(i, 0, 4), slope);
+ if (actual != expected[i]) return false;
+ }
+ return true;
+}
+
+/* One corner up slopes. */
+static_assert(CheckPartialPixelZ(SLOPE_N, {
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0,
+ 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0,
+ 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0,
+ 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0,
+ 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0,
+ 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0,
+ 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0,
+ 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}));
+
+static_assert(CheckPartialPixelZ(SLOPE_E, {
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7,
+ 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7,
+ 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
+ 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6,
+ 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5,
+ 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5,
+ 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}));
+
+static_assert(CheckPartialPixelZ(SLOPE_S, {
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4,
+ 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4,
+ 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5,
+ 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5,
+ 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6,
+ 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
+ 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7,
+ 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7}));
+
+static_assert(CheckPartialPixelZ(SLOPE_W, {
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0,
+ 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0,
+ 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0,
+ 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0,
+ 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0,
+ 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 0,
+ 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0}));
+
+/* Two corner up, diagonal slopes. */
+static_assert(CheckPartialPixelZ(SLOPE_NE, {
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}));
+
+static_assert(CheckPartialPixelZ(SLOPE_SE, {
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8}));
+
+static_assert(CheckPartialPixelZ(SLOPE_SW, {
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8}));
+
+static_assert(CheckPartialPixelZ(SLOPE_NW, {
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0}));
+
+/* Two opposite corner up slopes. */
+static_assert(CheckPartialPixelZ(SLOPE_NS, {
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0,
+ 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 1,
+ 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1,
+ 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 2,
+ 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 2, 2,
+ 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 2, 2, 3,
+ 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 2, 2, 3, 3,
+ 4, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 2, 2, 3, 3, 4,
+ 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4,
+ 3, 2, 2, 1, 1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5,
+ 2, 2, 1, 1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5,
+ 2, 1, 1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6,
+ 1, 1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
+ 1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7,
+ 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7}));
+
+static_assert(CheckPartialPixelZ(SLOPE_EW, {
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7,
+ 1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7,
+ 1, 1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
+ 2, 1, 1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6,
+ 2, 2, 1, 1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5,
+ 3, 2, 2, 1, 1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5,
+ 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4,
+ 4, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 2, 2, 3, 3, 4,
+ 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 2, 2, 3, 3,
+ 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 2, 2, 3,
+ 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 2, 2,
+ 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 2,
+ 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1,
+ 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, 1,
+ 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0}));
+
+/* Three corner up slopes. */
+static_assert(CheckPartialPixelZ(SLOPE_ENW, {
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 7,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 6,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 6, 6,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 6, 6, 5,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 6, 6, 5, 5,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 6, 6, 5, 5, 4,
+ 8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4,
+ 8, 8, 8, 8, 8, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3,
+ 8, 8, 8, 8, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3,
+ 8, 8, 8, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2,
+ 8, 8, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2,
+ 8, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1,
+ 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1}));
+
+static_assert(CheckPartialPixelZ(SLOPE_SEN, {
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8,
+ 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8,
+ 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8,
+ 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8,
+ 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8,
+ 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8,
+ 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8}));
+
+static_assert(CheckPartialPixelZ(SLOPE_WSE, {
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8,
+ 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8,
+ 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8,
+ 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8,
+ 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8,
+ 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8,
+ 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8,
+ 4, 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 5, 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 5, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 6, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8}));
+
+static_assert(CheckPartialPixelZ(SLOPE_NWS, {
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1,
+ 8, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1,
+ 8, 8, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2,
+ 8, 8, 8, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2,
+ 8, 8, 8, 8, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3,
+ 8, 8, 8, 8, 8, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3,
+ 8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 6, 6, 5, 5, 4,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 6, 6, 5, 5,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 6, 6, 5,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 6, 6,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 7, 6,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7, 7,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 7,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8}));
+
+/* Normal half tile slopes. */
+static_assert(CheckPartialPixelZ(HalftileSlope(SLOPE_N, CORNER_N), {
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}));
+
+static_assert(CheckPartialPixelZ(HalftileSlope(SLOPE_E, CORNER_E), {
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}));
+
+static_assert(CheckPartialPixelZ(HalftileSlope(SLOPE_S, CORNER_S), {
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 0, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8}));
+
+static_assert(CheckPartialPixelZ(HalftileSlope(SLOPE_W, CORNER_W), {
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 0}));
+
+/* Steep slopes. */
+static_assert(CheckPartialPixelZ(SLOPE_STEEP_N, {
+ 16, 15, 15, 14, 14, 13, 13, 12, 12, 11, 11, 10, 10, 9, 9, 8,
+ 15, 15, 14, 14, 13, 13, 12, 12, 11, 11, 10, 10, 9, 9, 8, 8,
+ 15, 14, 14, 13, 13, 12, 12, 11, 11, 10, 10, 9, 9, 8, 8, 7,
+ 14, 14, 13, 13, 12, 12, 11, 11, 10, 10, 9, 9, 8, 8, 7, 7,
+ 14, 13, 13, 12, 12, 11, 11, 10, 10, 9, 9, 8, 8, 7, 7, 6,
+ 13, 13, 12, 12, 11, 11, 10, 10, 9, 9, 8, 8, 7, 7, 6, 6,
+ 13, 12, 12, 11, 11, 10, 10, 9, 9, 8, 8, 7, 7, 6, 6, 5,
+ 12, 12, 11, 11, 10, 10, 9, 9, 8, 8, 7, 7, 6, 6, 5, 5,
+ 12, 11, 11, 10, 10, 9, 9, 8, 8, 7, 7, 6, 6, 5, 5, 4,
+ 11, 11, 10, 10, 9, 9, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4,
+ 11, 10, 10, 9, 9, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3,
+ 10, 10, 9, 9, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3,
+ 10, 9, 9, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2,
+ 9, 9, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2,
+ 9, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1,
+ 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1}));
+
+static_assert(CheckPartialPixelZ(SLOPE_STEEP_E, {
+ 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14, 15, 15, 16,
+ 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14, 15, 15,
+ 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14, 15,
+ 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14,
+ 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14,
+ 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13,
+ 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13,
+ 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12,
+ 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12,
+ 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
+ 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11,
+ 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10,
+ 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10,
+ 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9,
+ 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9,
+ 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8}));
+
+static_assert(CheckPartialPixelZ(SLOPE_STEEP_S, {
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8,
+ 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9,
+ 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9,
+ 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10,
+ 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10,
+ 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11,
+ 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
+ 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12,
+ 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12,
+ 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13,
+ 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13,
+ 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14,
+ 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14,
+ 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14, 15,
+ 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13, 14, 14, 15, 15}));
+
+static_assert(CheckPartialPixelZ(SLOPE_STEEP_W, {
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1,
+ 9, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1,
+ 9, 9, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2,
+ 10, 9, 9, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2,
+ 10, 10, 9, 9, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3,
+ 11, 10, 10, 9, 9, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3,
+ 11, 11, 10, 10, 9, 9, 8, 8, 7, 7, 6, 6, 5, 5, 4, 4,
+ 12, 11, 11, 10, 10, 9, 9, 8, 8, 7, 7, 6, 6, 5, 5, 4,
+ 12, 12, 11, 11, 10, 10, 9, 9, 8, 8, 7, 7, 6, 6, 5, 5,
+ 13, 12, 12, 11, 11, 10, 10, 9, 9, 8, 8, 7, 7, 6, 6, 5,
+ 13, 13, 12, 12, 11, 11, 10, 10, 9, 9, 8, 8, 7, 7, 6, 6,
+ 14, 13, 13, 12, 12, 11, 11, 10, 10, 9, 9, 8, 8, 7, 7, 6,
+ 14, 14, 13, 13, 12, 12, 11, 11, 10, 10, 9, 9, 8, 8, 7, 7,
+ 15, 14, 14, 13, 13, 12, 12, 11, 11, 10, 10, 9, 9, 8, 8, 7,
+ 15, 15, 14, 14, 13, 13, 12, 12, 11, 11, 10, 10, 9, 9, 8, 8}));
+
+/* Half tile on top of steep slopes. */
+static_assert(CheckPartialPixelZ(HalftileSlope(SLOPE_STEEP_N, CORNER_N), {
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 8,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 8, 7,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 8, 7, 7,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 8, 7, 7, 6,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 8, 7, 7, 6, 6,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 8, 7, 7, 6, 6, 5,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 8, 7, 7, 6, 6, 5, 5,
+ 16, 16, 16, 16, 16, 16, 16, 16, 8, 7, 7, 6, 6, 5, 5, 4,
+ 16, 16, 16, 16, 16, 16, 16, 8, 7, 7, 6, 6, 5, 5, 4, 4,
+ 16, 16, 16, 16, 16, 16, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3,
+ 16, 16, 16, 16, 16, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3,
+ 16, 16, 16, 16, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2,
+ 16, 16, 16, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2,
+ 16, 16, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1,
+ 16, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1}));
+
+static_assert(CheckPartialPixelZ(HalftileSlope(SLOPE_STEEP_E, CORNER_E), {
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 7, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 7, 7, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 6, 7, 7, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 6, 6, 7, 7, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 5, 6, 6, 7, 7, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 5, 5, 6, 6, 7, 7, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 4, 5, 5, 6, 6, 7, 7, 8, 16, 16, 16, 16, 16, 16, 16, 16,
+ 4, 4, 5, 5, 6, 6, 7, 7, 8, 16, 16, 16, 16, 16, 16, 16,
+ 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 16, 16, 16, 16, 16, 16,
+ 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 16, 16, 16, 16, 16,
+ 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 16, 16, 16, 16,
+ 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 16, 16, 16,
+ 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 16, 16,
+ 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 16}));
+
+static_assert(CheckPartialPixelZ(HalftileSlope(SLOPE_STEEP_S, CORNER_S), {
+ 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,
+ 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 16,
+ 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 16, 16,
+ 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 16, 16, 16,
+ 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 16, 16, 16, 16,
+ 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 16, 16, 16, 16, 16,
+ 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 16, 16, 16, 16, 16, 16,
+ 4, 4, 5, 5, 6, 6, 7, 7, 8, 16, 16, 16, 16, 16, 16, 16,
+ 4, 5, 5, 6, 6, 7, 7, 8, 16, 16, 16, 16, 16, 16, 16, 16,
+ 5, 5, 6, 6, 7, 7, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 5, 6, 6, 7, 7, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 6, 6, 7, 7, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 6, 7, 7, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 7, 7, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 7, 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
+ 8, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16}));
+
+static_assert(CheckPartialPixelZ(HalftileSlope(SLOPE_STEEP_W, CORNER_W), {
+ 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0,
+ 16, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1,
+ 16, 16, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1,
+ 16, 16, 16, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2,
+ 16, 16, 16, 16, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2,
+ 16, 16, 16, 16, 16, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3, 3,
+ 16, 16, 16, 16, 16, 16, 8, 7, 7, 6, 6, 5, 5, 4, 4, 3,
+ 16, 16, 16, 16, 16, 16, 16, 8, 7, 7, 6, 6, 5, 5, 4, 4,
+ 16, 16, 16, 16, 16, 16, 16, 16, 8, 7, 7, 6, 6, 5, 5, 4,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 8, 7, 7, 6, 6, 5, 5,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 8, 7, 7, 6, 6, 5,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 8, 7, 7, 6, 6,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 8, 7, 7, 6,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 8, 7, 7,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 8, 7,
+ 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 8}));