backend-infra-engineer: Post v0.3.9-hotfix7 snapshot (build cleanup)

test/unit/zelda3/dungeon/bpp_conversion_test.cc

@@ -0,0 +1,125 @@
+#include <gtest/gtest.h>
+#include <array>
+#include <cstdint>
+
+namespace yaze {
+namespace zelda3 {
+namespace test {
+
+class Bpp3To8ConversionTest : public ::testing::Test {
+ protected:
+  // Simulates the conversion algorithm
+  static const uint8_t kBitMask[8];
+
+  void Convert3BppTo8Bpp(const uint8_t* src_3bpp, uint8_t* dest_8bpp) {
+    // Convert one 8x8 tile from 3BPP (24 bytes) to 8BPP unpacked (64 bytes)
+    for (int row = 0; row < 8; row++) {
+      uint8_t plane0 = src_3bpp[row * 2];
+      uint8_t plane1 = src_3bpp[row * 2 + 1];
+      uint8_t plane2 = src_3bpp[16 + row];
+
+      for (int nibble_pair = 0; nibble_pair < 4; nibble_pair++) {
+        uint8_t pix1 = 0, pix2 = 0;
+
+        int bit1 = nibble_pair * 2;
+        int bit2 = nibble_pair * 2 + 1;
+
+        if (plane0 & kBitMask[bit1]) pix1 |= 1;
+        if (plane1 & kBitMask[bit1]) pix1 |= 2;
+        if (plane2 & kBitMask[bit1]) pix1 |= 4;
+
+        if (plane0 & kBitMask[bit2]) pix2 |= 1;
+        if (plane1 & kBitMask[bit2]) pix2 |= 2;
+        if (plane2 & kBitMask[bit2]) pix2 |= 4;
+
+        dest_8bpp[row * 8 + (nibble_pair * 2)] = pix1;
+        dest_8bpp[row * 8 + (nibble_pair * 2) + 1] = pix2;
+      }
+    }
+  }
+};
+
+const uint8_t Bpp3To8ConversionTest::kBitMask[8] = {
+  0x80, 0x40, 0x20, 0x10, 0x08, 0x04, 0x02, 0x01
+};
+
+// Test that all-zero 3BPP produces all-zero 8BPP
+TEST_F(Bpp3To8ConversionTest, ZeroInputProducesZeroOutput) {
+  std::array<uint8_t, 24> src_3bpp = {};  // All zeros
+  std::array<uint8_t, 64> dest_8bpp = {};
+
+  Convert3BppTo8Bpp(src_3bpp.data(), dest_8bpp.data());
+
+  for (int i = 0; i < 64; i++) {
+    EXPECT_EQ(dest_8bpp[i], 0) << "Byte " << i << " should be zero";
+  }
+}
+
+// Test that all-ones in plane0 produces correct pattern
+TEST_F(Bpp3To8ConversionTest, Plane0OnlyProducesColorIndex1) {
+  std::array<uint8_t, 24> src_3bpp = {};
+  // Set plane0 to all 1s for first row
+  src_3bpp[0] = 0xFF;  // Row 0, plane 0
+
+  std::array<uint8_t, 64> dest_8bpp = {};
+  Convert3BppTo8Bpp(src_3bpp.data(), dest_8bpp.data());
+
+  // First row should have color index 1 for all pixels
+  // Unpacked: 1, 1, 1, 1...
+  EXPECT_EQ(dest_8bpp[0], 1);
+  EXPECT_EQ(dest_8bpp[1], 1);
+  EXPECT_EQ(dest_8bpp[2], 1);
+  EXPECT_EQ(dest_8bpp[3], 1);
+}
+
+// Test that all planes set produces color index 7
+TEST_F(Bpp3To8ConversionTest, AllPlanesProducesColorIndex7) {
+  std::array<uint8_t, 24> src_3bpp = {};
+  // Set all planes for first row
+  src_3bpp[0] = 0xFF;   // Row 0, plane 0
+  src_3bpp[1] = 0xFF;   // Row 0, plane 1
+  src_3bpp[16] = 0xFF;  // Row 0, plane 2
+
+  std::array<uint8_t, 64> dest_8bpp = {};
+  Convert3BppTo8Bpp(src_3bpp.data(), dest_8bpp.data());
+
+  // First row should have color index 7 for all pixels
+  // Unpacked: 7, 7, 7, 7...
+  EXPECT_EQ(dest_8bpp[0], 7);
+  EXPECT_EQ(dest_8bpp[1], 7);
+  EXPECT_EQ(dest_8bpp[2], 7);
+  EXPECT_EQ(dest_8bpp[3], 7);
+}
+
+// Test alternating pixel pattern
+TEST_F(Bpp3To8ConversionTest, AlternatingPixelsCorrectlyPacked) {
+  std::array<uint8_t, 24> src_3bpp = {};
+  // Alternate: 0xAA = 10101010 (pixels 0,2,4,6 set)
+  src_3bpp[0] = 0xAA;  // Plane 0 only
+
+  std::array<uint8_t, 64> dest_8bpp = {};
+  Convert3BppTo8Bpp(src_3bpp.data(), dest_8bpp.data());
+
+  // Pixels 0,2,4,6 have color 1; pixels 1,3,5,7 have color 0
+  // Unpacked: 1, 0, 1, 0...
+  EXPECT_EQ(dest_8bpp[0], 1);
+  EXPECT_EQ(dest_8bpp[1], 0);
+  EXPECT_EQ(dest_8bpp[2], 1);
+  EXPECT_EQ(dest_8bpp[3], 0);
+}
+
+// Test output buffer size matches expected 8BPP format
+TEST_F(Bpp3To8ConversionTest, OutputSizeIs64BytesPerTile) {
+  // 8 rows * 8 bytes per row = 64 bytes
+  constexpr int kExpectedOutputSize = 64;
+  std::array<uint8_t, 24> src_3bpp = {};
+  std::array<uint8_t, kExpectedOutputSize> dest_8bpp = {};
+
+  Convert3BppTo8Bpp(src_3bpp.data(), dest_8bpp.data());
+  // If we got here without crash, size is correct
+  SUCCEED();
+}
+
+}  // namespace test
+}  // namespace zelda3
+}  // namespace yaze