Merge pull request #1377 from FernandoS27/faster-swizzle

Improved Fast Swizzle and Legacy Swizzle

src/video_core/textures/decoders.cpp

@@ -13,47 +13,20 @@
 namespace Tegra::Texture {
 
 /**
+ * This table represents the internal swizzle of a gob,
+ * in format 16 bytes x 2 sector packing.
  * Calculates the offset of an (x, y) position within a swizzled texture.
- * Taken from the Tegra X1 TRM.
+ * Taken from the Tegra X1 Technical Reference Manual. pages 1187-1188
  */
-static u32 GetSwizzleOffset(u32 x, u32 y, u32 image_width, u32 bytes_per_pixel, u32 block_height) {
-    // Round up to the next gob
-    const u32 image_width_in_gobs{(image_width * bytes_per_pixel + 63) / 64};
-
-    u32 GOB_address = 0 + (y / (8 * block_height)) * 512 * block_height * image_width_in_gobs +
-                      (x * bytes_per_pixel / 64) * 512 * block_height +
-                      (y % (8 * block_height) / 8) * 512;
-    x *= bytes_per_pixel;
-    u32 address = GOB_address + ((x % 64) / 32) * 256 + ((y % 8) / 2) * 64 + ((x % 32) / 16) * 32 +
-                  (y % 2) * 16 + (x % 16);
-
-    return address;
-}
-
-void CopySwizzledData(u32 width, u32 height, u32 bytes_per_pixel, u32 out_bytes_per_pixel,
-                      u8* swizzled_data, u8* unswizzled_data, bool unswizzle, u32 block_height) {
-    u8* data_ptrs[2];
-    for (unsigned y = 0; y < height; ++y) {
-        for (unsigned x = 0; x < width; ++x) {
-            u32 swizzle_offset = GetSwizzleOffset(x, y, width, bytes_per_pixel, block_height);
-            u32 pixel_index = (x + y * width) * out_bytes_per_pixel;
-
-            data_ptrs[unswizzle] = swizzled_data + swizzle_offset;
-            data_ptrs[!unswizzle] = &unswizzled_data[pixel_index];
-
-            std::memcpy(data_ptrs[0], data_ptrs[1], bytes_per_pixel);
-        }
-    }
-}
-
-template <std::size_t N, std::size_t M>
+template <std::size_t N, std::size_t M, u32 Align>
 struct alignas(64) SwizzleTable {
+    static_assert(M * Align == 64, "Swizzle Table does not align to GOB");
     constexpr SwizzleTable() {
         for (u32 y = 0; y < N; ++y) {
             for (u32 x = 0; x < M; ++x) {
-                const u32 x2 = x * 16;
+                const u32 x2 = x * Align;
                 values[y][x] = static_cast<u16>(((x2 % 64) / 32) * 256 + ((y % 8) / 2) * 64 +
-                                                ((x2 % 32) / 16) * 32 + (y % 2) * 16);
+                                                ((x2 % 32) / 16) * 32 + (y % 2) * 16 + (x2 % 16));
             }
         }
     }
@@ -63,24 +36,60 @@ struct alignas(64) SwizzleTable {
     std::array<std::array<u16, M>, N> values{};
 };
 
-constexpr auto swizzle_table = SwizzleTable<8, 4>();
+constexpr auto legacy_swizzle_table = SwizzleTable<8, 64, 1>();
+constexpr auto fast_swizzle_table = SwizzleTable<8, 4, 16>();
 
-void FastSwizzleData(u32 width, u32 height, u32 bytes_per_pixel, u8* swizzled_data,
-                     u8* unswizzled_data, bool unswizzle, u32 block_height) {
+static void LegacySwizzleData(u32 width, u32 height, u32 bytes_per_pixel, u32 out_bytes_per_pixel,
+                              u8* swizzled_data, u8* unswizzled_data, bool unswizzle,
+                              u32 block_height) {
+    std::array<u8*, 2> data_ptrs;
+    const std::size_t stride = width * bytes_per_pixel;
+    const std::size_t gobs_in_x = 64;
+    const std::size_t gobs_in_y = 8;
+    const std::size_t gobs_size = gobs_in_x * gobs_in_y;
+    const std::size_t image_width_in_gobs{(stride + gobs_in_x - 1) / gobs_in_x};
+    for (std::size_t y = 0; y < height; ++y) {
+        const std::size_t gob_y_address =
+            (y / (gobs_in_y * block_height)) * gobs_size * block_height * image_width_in_gobs +
+            (y % (gobs_in_y * block_height) / gobs_in_y) * gobs_size;
+        const auto& table = legacy_swizzle_table[y % gobs_in_y];
+        for (std::size_t x = 0; x < width; ++x) {
+            const std::size_t gob_address =
+                gob_y_address + (x * bytes_per_pixel / gobs_in_x) * gobs_size * block_height;
+            const std::size_t x2 = x * bytes_per_pixel;
+            const std::size_t swizzle_offset = gob_address + table[x2 % gobs_in_x];
+            const std::size_t pixel_index = (x + y * width) * out_bytes_per_pixel;
+
+            data_ptrs[unswizzle] = swizzled_data + swizzle_offset;
+            data_ptrs[!unswizzle] = unswizzled_data + pixel_index;
+
+            std::memcpy(data_ptrs[0], data_ptrs[1], bytes_per_pixel);
+        }
+    }
+}
+
+static void FastSwizzleData(u32 width, u32 height, u32 bytes_per_pixel, u32 out_bytes_per_pixel,
+                            u8* swizzled_data, u8* unswizzled_data, bool unswizzle,
+                            u32 block_height) {
     std::array<u8*, 2> data_ptrs;
     const std::size_t stride{width * bytes_per_pixel};
-    const std::size_t image_width_in_gobs{(stride + 63) / 64};
+    const std::size_t gobs_in_x = 64;
+    const std::size_t gobs_in_y = 8;
+    const std::size_t gobs_size = gobs_in_x * gobs_in_y;
+    const std::size_t image_width_in_gobs{(stride + gobs_in_x - 1) / gobs_in_x};
     const std::size_t copy_size{16};
     for (std::size_t y = 0; y < height; ++y) {
         const std::size_t initial_gob =
-            (y / (8 * block_height)) * 512 * block_height * image_width_in_gobs +
-            (y % (8 * block_height) / 8) * 512;
-        const std::size_t pixel_base{y * width * bytes_per_pixel};
-        const auto& table = swizzle_table[y % 8];
+            (y / (gobs_in_y * block_height)) * gobs_size * block_height * image_width_in_gobs +
+            (y % (gobs_in_y * block_height) / gobs_in_y) * gobs_size;
+        const std::size_t pixel_base{y * width * out_bytes_per_pixel};
+        const auto& table = fast_swizzle_table[y % gobs_in_y];
         for (std::size_t xb = 0; xb < stride; xb += copy_size) {
-            const std::size_t gob_address{initial_gob + (xb / 64) * 512 * block_height};
+            const std::size_t gob_address{initial_gob +
+                                          (xb / gobs_in_x) * gobs_size * block_height};
             const std::size_t swizzle_offset{gob_address + table[(xb / 16) % 4]};
-            const std::size_t pixel_index{xb + pixel_base};
+            const std::size_t out_x = xb * out_bytes_per_pixel / bytes_per_pixel;
+            const std::size_t pixel_index{out_x + pixel_base};
             data_ptrs[unswizzle] = swizzled_data + swizzle_offset;
             data_ptrs[!unswizzle] = unswizzled_data + pixel_index;
             std::memcpy(data_ptrs[0], data_ptrs[1], copy_size);
@@ -88,6 +97,17 @@ void FastSwizzleData(u32 width, u32 height, u32 bytes_per_pixel, u8* swizzled_da
     }
 }
 
+void CopySwizzledData(u32 width, u32 height, u32 bytes_per_pixel, u32 out_bytes_per_pixel,
+                      u8* swizzled_data, u8* unswizzled_data, bool unswizzle, u32 block_height) {
+    if (bytes_per_pixel % 3 != 0 && (width * bytes_per_pixel) % 16 == 0) {
+        FastSwizzleData(width, height, bytes_per_pixel, out_bytes_per_pixel, swizzled_data,
+                        unswizzled_data, unswizzle, block_height);
+    } else {
+        LegacySwizzleData(width, height, bytes_per_pixel, out_bytes_per_pixel, swizzled_data,
+                          unswizzled_data, unswizzle, block_height);
+    }
+}
+
 u32 BytesPerPixel(TextureFormat format) {
     switch (format) {
     case TextureFormat::DXT1:
@@ -134,13 +154,8 @@ u32 BytesPerPixel(TextureFormat format) {
 std::vector<u8> UnswizzleTexture(VAddr address, u32 tile_size, u32 bytes_per_pixel, u32 width,
                                  u32 height, u32 block_height) {
     std::vector<u8> unswizzled_data(width * height * bytes_per_pixel);
-    if (bytes_per_pixel % 3 != 0 && (width * bytes_per_pixel) % 16 == 0) {
-        FastSwizzleData(width / tile_size, height / tile_size, bytes_per_pixel,
-                        Memory::GetPointer(address), unswizzled_data.data(), true, block_height);
-    } else {
-        CopySwizzledData(width / tile_size, height / tile_size, bytes_per_pixel, bytes_per_pixel,
-                         Memory::GetPointer(address), unswizzled_data.data(), true, block_height);
-    }
+    CopySwizzledData(width / tile_size, height / tile_size, bytes_per_pixel, bytes_per_pixel,
+                     Memory::GetPointer(address), unswizzled_data.data(), true, block_height);
     return unswizzled_data;
 }