1 files changed, 69 insertions, 93 deletions

diff --git a/src/video_core/textures/decoders.cpp b/src/video_core/textures/decoders.cpp
index d6750b174..5e2d3ac32 100644
--- a/src/video_core/textures/decoders.cpp
+++ b/src/video_core/textures/decoders.cpp
@@ -40,97 +40,56 @@ struct alignas(64) SwizzleTable {
 constexpr auto legacy_swizzle_table = SwizzleTable<8, 64, 1>();
 constexpr auto fast_swizzle_table = SwizzleTable<8, 4, 16>();
 
-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 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 / (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 / gobs_in_x) * gobs_size * block_height};
-            const std::size_t swizzle_offset{gob_address + table[(xb / 16) % 4]};
-            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);
-        }
-    }
-}
-
-void Precise3DProcessGobs(u8* swizzled_data, u8* unswizzled_data, bool unswizzle, const u32 x_start,
-                       const u32 y_start, const u32 z_start, const u32 x_end, const u32 y_end,
-                       const u32 z_end, const u32 tile_offset, const u32 xy_block_size,
-                       const u32 layer_z, const u32 stride_x, const u32 bytes_per_pixel,
-                       const u32 out_bytes_per_pixel) {
+/**
+ * This function manages ALL the GOBs(Group of Bytes) Inside a single block.
+ * Instead of going gob by gob, we map the coordinates inside a block and manage from
+ * those. Block_Width is assumed to be 1.
+ */
+void Precise3DProcessBlock(u8* swizzled_data, u8* unswizzled_data, const bool unswizzle,
+                           const u32 x_start, const u32 y_start, const u32 z_start, const u32 x_end,
+                           const u32 y_end, const u32 z_end, const u32 tile_offset,
+                           const u32 xy_block_size, const u32 layer_z, const u32 stride_x,
+                           const u32 bytes_per_pixel, const u32 out_bytes_per_pixel) {
     std::array<u8*, 2> data_ptrs;
     u32 z_adress = tile_offset;
-    const u32 gob_size = 64 * 8 * 1;
+    const u32 gob_size_x = 64;
+    const u32 gob_size_y = 8;
+    const u32 gob_size_z = 1;
+    const u32 gob_size = gob_size_x * gob_size_y * gob_size_z;
     for (u32 z = z_start; z < z_end; z++) {
         u32 y_adress = z_adress;
         u32 pixel_base = layer_z * z + y_start * stride_x;
         for (u32 y = y_start; y < y_end; y++) {
-            const auto& table = legacy_swizzle_table[y % 8];
+            const auto& table = legacy_swizzle_table[y % gob_size_y];
             for (u32 x = x_start; x < x_end; x++) {
-                const u32 swizzle_offset{y_adress + table[x * bytes_per_pixel % 64]};
+                const u32 swizzle_offset{y_adress + table[x * bytes_per_pixel % gob_size_x]};
                 const u32 pixel_index{x * out_bytes_per_pixel + pixel_base};
                 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);
             }
             pixel_base += stride_x;
-            if ((y + 1) % 8 == 0)
+            if ((y + 1) % gob_size_y == 0)
                 y_adress += gob_size;
         }
         z_adress += xy_block_size;
     }
 }
 
-void Precise3DSwizzledData(u8* swizzled_data, u8* unswizzled_data, bool unswizzle, u32 width,
-                        u32 height, u32 depth, u32 bytes_per_pixel, u32 out_bytes_per_pixel,
-                        u32 block_height, u32 block_depth) {
-    auto div_ceil = [](u32 x, u32 y) { return ((x + y - 1) / y); };
-
+/**
+ * This function unswizzles or swizzles a texture by mapping Linear to BlockLinear Textue.
+ * The body of this function takes care of splitting the swizzled texture into blocks,
+ * and managing the extents of it. Once all the parameters of a single block are obtained,
+ * the function calls '3DProcessBlock' to process that particular Block.
+ *
+ * Documentation for the memory layout and decoding can be found at:
+ *  https://envytools.readthedocs.io/en/latest/hw/memory/g80-surface.html#blocklinear-surfaces
+ */
+void Precise3DSwizzledData(u8* swizzled_data, u8* unswizzled_data, const bool unswizzle,
+                           const u32 width, const u32 height, const u32 depth,
+                           const u32 bytes_per_pixel, const u32 out_bytes_per_pixel,
+                           const u32 block_height, const u32 block_depth) {
+    auto div_ceil = [](const u32 x, const u32 y) { return ((x + y - 1) / y); };
     const u32 stride_x = width * out_bytes_per_pixel;
     const u32 layer_z = height * stride_x;
     const u32 gob_x_bytes = 64;
@@ -157,33 +116,41 @@ void Precise3DSwizzledData(u8* swizzled_data, u8* unswizzled_data, bool unswizzl
             for (u32 xb = 0; xb < blocks_on_x; xb++) {
                 const u32 x_start = xb * block_x_elements;
                 const u32 x_end = std::min(width, x_start + block_x_elements);
-                Precise3DProcessGobs(swizzled_data, unswizzled_data, unswizzle, x_start, y_start,
-                                  z_start, x_end, y_end, z_end, tile_offset, xy_block_size, layer_z,
-                                  stride_x, bytes_per_pixel, out_bytes_per_pixel);
+                Precise3DProcessBlock(swizzled_data, unswizzled_data, unswizzle, x_start, y_start,
+                                      z_start, x_end, y_end, z_end, tile_offset, xy_block_size,
+                                      layer_z, stride_x, bytes_per_pixel, out_bytes_per_pixel);
                 tile_offset += block_size;
             }
         }
     }
 }
 
-void Fast3DProcessGobs(u8* swizzled_data, u8* unswizzled_data, bool unswizzle, const u32 x_start,
-                       const u32 y_start, const u32 z_start, const u32 x_end, const u32 y_end,
-                       const u32 z_end, const u32 tile_offset, const u32 xy_block_size,
-                       const u32 layer_z, const u32 stride_x, const u32 bytes_per_pixel,
-                       const u32 out_bytes_per_pixel) {
+/**
+ * This function manages ALL the GOBs(Group of Bytes) Inside a single block.
+ * Instead of going gob by gob, we map the coordinates inside a block and manage from
+ * those. Block_Width is assumed to be 1.
+ */
+void Fast3DProcessBlock(u8* swizzled_data, u8* unswizzled_data, const bool unswizzle,
+                        const u32 x_start, const u32 y_start, const u32 z_start, const u32 x_end,
+                        const u32 y_end, const u32 z_end, const u32 tile_offset,
+                        const u32 xy_block_size, const u32 layer_z, const u32 stride_x,
+                        const u32 bytes_per_pixel, const u32 out_bytes_per_pixel) {
     std::array<u8*, 2> data_ptrs;
     u32 z_adress = tile_offset;
     const u32 x_startb = x_start * bytes_per_pixel;
     const u32 x_endb = x_end * bytes_per_pixel;
     const u32 copy_size = 16;
-    const u32 gob_size = 64 * 8 * 1;
+    const u32 gob_size_x = 64;
+    const u32 gob_size_y = 8;
+    const u32 gob_size_z = 1;
+    const u32 gob_size = gob_size_x * gob_size_y * gob_size_z;
     for (u32 z = z_start; z < z_end; z++) {
         u32 y_adress = z_adress;
         u32 pixel_base = layer_z * z + y_start * stride_x;
         for (u32 y = y_start; y < y_end; y++) {
-            const auto& table = fast_swizzle_table[y % 8];
+            const auto& table = fast_swizzle_table[y % gob_size_y];
             for (u32 xb = x_startb; xb < x_endb; xb += copy_size) {
-                const u32 swizzle_offset{y_adress + table[(xb / 16) % 4]};
+                const u32 swizzle_offset{y_adress + table[(xb / copy_size) % 4]};
                 const u32 out_x = xb * out_bytes_per_pixel / bytes_per_pixel;
                 const u32 pixel_index{out_x + pixel_base};
                 data_ptrs[unswizzle] = swizzled_data + swizzle_offset;
@@ -191,18 +158,27 @@ void Fast3DProcessGobs(u8* swizzled_data, u8* unswizzled_data, bool unswizzle, c
                 std::memcpy(data_ptrs[0], data_ptrs[1], copy_size);
             }
             pixel_base += stride_x;
-            if ((y + 1) % 8 == 0)
+            if ((y + 1) % gob_size_y == 0)
                 y_adress += gob_size;
         }
         z_adress += xy_block_size;
     }
 }
 
-void Fast3DSwizzledData(u8* swizzled_data, u8* unswizzled_data, bool unswizzle, u32 width,
-                        u32 height, u32 depth, u32 bytes_per_pixel, u32 out_bytes_per_pixel,
-                        u32 block_height, u32 block_depth) {
-    auto div_ceil = [](u32 x, u32 y) { return ((x + y - 1) / y); };
-
+/**
+ * This function unswizzles or swizzles a texture by mapping Linear to BlockLinear Textue.
+ * The body of this function takes care of splitting the swizzled texture into blocks,
+ * and managing the extents of it. Once all the parameters of a single block are obtained,
+ * the function calls '3DProcessBlock' to process that particular Block.
+ *
+ * Documentation for the memory layout and decoding can be found at:
+ *  https://envytools.readthedocs.io/en/latest/hw/memory/g80-surface.html#blocklinear-surfaces
+ */
+void Fast3DSwizzledData(u8* swizzled_data, u8* unswizzled_data, const bool unswizzle,
+                        const u32 width, const u32 height, const u32 depth,
+                        const u32 bytes_per_pixel, const u32 out_bytes_per_pixel,
+                        const u32 block_height, const u32 block_depth) {
+    auto div_ceil = [](const u32 x, const u32 y) { return ((x + y - 1) / y); };
     const u32 stride_x = width * out_bytes_per_pixel;
     const u32 layer_z = height * stride_x;
     const u32 gob_x_bytes = 64;
@@ -229,9 +205,9 @@ void Fast3DSwizzledData(u8* swizzled_data, u8* unswizzled_data, bool unswizzle,
             for (u32 xb = 0; xb < blocks_on_x; xb++) {
                 const u32 x_start = xb * block_x_elements;
                 const u32 x_end = std::min(width, x_start + block_x_elements);
-                Fast3DProcessGobs(swizzled_data, unswizzled_data, unswizzle, x_start, y_start,
-                                  z_start, x_end, y_end, z_end, tile_offset, xy_block_size, layer_z,
-                                  stride_x, bytes_per_pixel, out_bytes_per_pixel);
+                Fast3DProcessBlock(swizzled_data, unswizzled_data, unswizzle, x_start, y_start,
+                                   z_start, x_end, y_end, z_end, tile_offset, xy_block_size,
+                                   layer_z, stride_x, bytes_per_pixel, out_bytes_per_pixel);
                 tile_offset += block_size;
             }
         }
@@ -245,7 +221,7 @@ void CopySwizzledData(u32 width, u32 height, u32 bytes_per_pixel, u32 out_bytes_
                            bytes_per_pixel, out_bytes_per_pixel, block_height, 1U);
     } else {
         Precise3DSwizzledData(swizzled_data, unswizzled_data, unswizzle, width, height, 1U,
-                           bytes_per_pixel, out_bytes_per_pixel, block_height, 1U);
+                              bytes_per_pixel, out_bytes_per_pixel, block_height, 1U);
     }
 }