feat: Add OpenGL ZBC clear support and refactor ZBC management

Moved ZBCManager to `video_core/zbc_manager.cpp/h` for modularity. Added
`gl_zbc_clear.cpp/h` for efficient OpenGL color, depth, and stencil clears.
Updated `RasterizerOpenGL::Clear` to use ZBC with fallback. Added stencil
type validation. Fixed color mask and logging. Updated `CMakeLists.txt`.
Enhances performance and code organization.

Signed-off-by: Zephyron <zephyron@citron-emu.org>

src/core/hle/service/nvdrv/devices/nvhost_ctrl_gpu.cpp

@@ -10,59 +10,21 @@
 #include "core/hle/service/nvdrv/devices/ioctl_serialization.h"
 #include "core/hle/service/nvdrv/devices/nvhost_ctrl_gpu.h"
 #include "core/hle/service/nvdrv/nvdrv.h"
+#include "video_core/zbc_manager.h"
 
 namespace Service::Nvidia::Devices {
 
 // ZBC helper functions for GPU clearing operations
 namespace ZBC {
     std::optional<std::array<u32, 4>> GetColor(u32 format, u32 type) {
-        return ZBCManager::Instance().GetZBCColor(format, type);
+        return VideoCore::ZBCManager::Instance().GetZBCColor(format, type);
     }
 
     std::optional<u32> GetDepth(u32 format, u32 type) {
-        return ZBCManager::Instance().GetZBCDepth(format, type);
+        return VideoCore::ZBCManager::Instance().GetZBCDepth(format, type);
     }
 }
 
-// ZBCManager implementation
-std::optional<std::array<u32, 4>> ZBCManager::GetZBCColor(u32 format, u32 type) const {
-    std::scoped_lock lock{zbc_table_mutex};
-    const auto key = std::make_pair(format, type);
-    const auto it = zbc_table.find(key);
-    if (it != zbc_table.end()) {
-        return it->second.color_ds;
-    }
-    return std::nullopt;
-}
-
-std::optional<u32> ZBCManager::GetZBCDepth(u32 format, u32 type) const {
-    std::scoped_lock lock{zbc_table_mutex};
-    const auto key = std::make_pair(format, type);
-    const auto it = zbc_table.find(key);
-    if (it != zbc_table.end()) {
-        return it->second.depth;
-    }
-    return std::nullopt;
-}
-
-void ZBCManager::StoreZBCEntry(u32 format, u32 type, const std::array<u32, 4>& color_ds,
-                               const std::array<u32, 4>& color_l2, u32 depth) {
-    std::scoped_lock lock{zbc_table_mutex};
-
-    ZBCEntry entry;
-    entry.color_ds = color_ds;
-    entry.color_l2 = color_l2;
-    entry.depth = depth;
-    entry.format = format;
-    entry.type = type;
-    entry.ref_count = 1;
-
-    const auto key = std::make_pair(format, type);
-    zbc_table[key] = entry;
-
-    LOG_DEBUG(Service_NVDRV, "Global ZBCManager: Stored entry format=0x{:X}, type=0x{:X}, depth=0x{:X}",
-              format, type, depth);
-}
 
 nvhost_ctrl_gpu::nvhost_ctrl_gpu(Core::System& system_, EventInterface& events_interface_)
     : nvdevice{system_}, events_interface{events_interface_} {
@@ -143,11 +105,11 @@ void nvhost_ctrl_gpu::OnClose(DeviceFD fd) {}
 
 // ZBC table management methods
 std::optional<std::array<u32, 4>> nvhost_ctrl_gpu::GetZBCColor(u32 format, u32 type) const {
-    return ZBCManager::Instance().GetZBCColor(format, type);
+    return VideoCore::ZBCManager::Instance().GetZBCColor(format, type);
 }
 
 std::optional<u32> nvhost_ctrl_gpu::GetZBCDepth(u32 format, u32 type) const {
-    return ZBCManager::Instance().GetZBCDepth(format, type);
+    return VideoCore::ZBCManager::Instance().GetZBCDepth(format, type);
 }
 
 void nvhost_ctrl_gpu::StoreZBCEntry(const IoctlZbcSetTable& params) {
@@ -166,7 +128,7 @@ void nvhost_ctrl_gpu::StoreZBCEntry(const IoctlZbcSetTable& params) {
     zbc_table[key] = entry;
 
     // Also store in global ZBCManager for GPU access
-    ZBCManager::Instance().StoreZBCEntry(params.format, params.type, entry.color_ds, entry.color_l2, params.depth);
+    VideoCore::ZBCManager::Instance().StoreZBCEntry(params.format, params.type, entry.color_ds, entry.color_l2, params.depth);
 
     LOG_DEBUG(Service_NVDRV, "Stored ZBC entry: format=0x{:X}, type=0x{:X}, depth=0x{:X}",
               params.format, params.type, params.depth);
@@ -331,8 +293,8 @@ NvResult nvhost_ctrl_gpu::ZBCSetTable(IoctlZbcSetTable& params) {
         return NvResult::BadParameter;
     }
 
-    // Validate the type parameter (typically 0 for color, 1 for depth)
+    // Validate the type parameter (0=color, 1=depth, 2=stencil)
-    if (params.type > 1) {
+    if (params.type > 2) {
         LOG_WARNING(Service_NVDRV, "Invalid ZBC type: 0x{:X}", params.type);
         return NvResult::BadParameter;
     }
@@ -344,7 +306,7 @@ NvResult nvhost_ctrl_gpu::ZBCSetTable(IoctlZbcSetTable& params) {
     LOG_DEBUG(Service_NVDRV, "ZBC color_ds: [0x{:08X}, 0x{:08X}, 0x{:08X}, 0x{:08X}]",
               params.color_ds[0], params.color_ds[1], params.color_ds[2], params.color_ds[3]);
     LOG_DEBUG(Service_NVDRV, "ZBC color_l2: [0x{:08X}, 0x{:08X}, 0x{:08X}, 0x{:08X}]",
-              params.color_ds[0], params.color_ds[1], params.color_ds[2], params.color_ds[3]);
+              params.color_l2[0], params.color_l2[1], params.color_l2[2], params.color_l2[3]);
 
     return NvResult::Success;
 }

src/video_core/CMakeLists.txt

@@ -33,6 +33,8 @@ add_library(video_core STATIC
     delayed_destruction_ring.h
     dirty_flags.cpp
     dirty_flags.h
+    zbc_manager.cpp
+    zbc_manager.h
     dma_pusher.cpp
     dma_pusher.h
     engines/sw_blitter/blitter.cpp
@@ -152,6 +154,8 @@ add_library(video_core STATIC
     renderer_opengl/gl_graphics_pipeline.h
     renderer_opengl/gl_rasterizer.cpp
     renderer_opengl/gl_rasterizer.h
+    renderer_opengl/gl_zbc_clear.cpp
+    renderer_opengl/gl_zbc_clear.h
     renderer_opengl/gl_resource_manager.cpp
     renderer_opengl/gl_resource_manager.h
     renderer_opengl/gl_shader_cache.cpp
@@ -197,6 +201,8 @@ add_library(video_core STATIC
     renderer_vulkan/present/window_adapt_pass.h
     renderer_vulkan/blit_image.cpp
     renderer_vulkan/blit_image.h
+    renderer_vulkan/vk_zbc_clear.cpp
+    renderer_vulkan/vk_zbc_clear.h
     renderer_vulkan/fixed_pipeline_state.cpp
     renderer_vulkan/fixed_pipeline_state.h
     renderer_vulkan/maxwell_to_vk.cpp

src/video_core/renderer_opengl/gl_rasterizer.cpp

@@ -23,6 +23,7 @@
 #include "video_core/renderer_opengl/gl_device.h"
 #include "video_core/renderer_opengl/gl_query_cache.h"
 #include "video_core/renderer_opengl/gl_rasterizer.h"
+#include "video_core/renderer_opengl/gl_zbc_clear.h"
 #include "video_core/renderer_opengl/gl_shader_cache.h"
 #include "video_core/renderer_opengl/gl_staging_buffer_pool.h"
 #include "video_core/renderer_opengl/gl_texture_cache.h"
@@ -213,15 +214,50 @@ void RasterizerOpenGL::Clear(u32 layer_count) {
     }
     UNIMPLEMENTED_IF(regs.clear_control.use_viewport_clip0);
 
+    // Try to use ZBC (Zero Bandwidth Clear) for efficient clearing
+    bool zbc_used = false;
+
     if (use_color) {
-        glClearBufferfv(GL_COLOR, regs.clear_surface.RT, regs.clear_color.data());
+        // Try ZBC clear first, fall back to regular clear if not available
+        const u32 rt_index = regs.clear_surface.RT;
+        const u32 format = static_cast<u32>(regs.rt[rt_index].format);
+        const u32 type = 0; // Color clear type
+        if (!OpenGL::ZBCClear::ClearColor(format, type, rt_index)) {
+            glClearBufferfv(GL_COLOR, rt_index, regs.clear_color.data());
+        } else {
+            zbc_used = true;
+        }
     }
+
     if (use_depth && use_stencil) {
-        glClearBufferfi(GL_DEPTH_STENCIL, 0, regs.clear_depth, regs.clear_stencil);
+        const u32 format = static_cast<u32>(regs.zeta.format);
+        const u32 type = 1; // Depth clear type
+        if (!OpenGL::ZBCClear::ClearDepthStencil(format, type, regs.clear_stencil)) {
+            glClearBufferfi(GL_DEPTH_STENCIL, 0, regs.clear_depth, regs.clear_stencil);
+        } else {
+            zbc_used = true;
+        }
     } else if (use_depth) {
-        glClearBufferfv(GL_DEPTH, 0, &regs.clear_depth);
+        const u32 format = static_cast<u32>(regs.zeta.format);
+        const u32 type = 1; // Depth clear type
+        if (!OpenGL::ZBCClear::ClearDepth(format, type)) {
+            glClearBufferfv(GL_DEPTH, 0, &regs.clear_depth);
+        } else {
+            zbc_used = true;
+        }
     } else if (use_stencil) {
-        glClearBufferiv(GL_STENCIL, 0, &regs.clear_stencil);
+        // Try ZBC stencil clear first, fall back to regular clear if not available
+        const u32 format = static_cast<u32>(regs.zeta.format);
+        const u32 type = 2; // Stencil clear type
+        if (!OpenGL::ZBCClear::ClearStencil(format, type, regs.clear_stencil)) {
+            glClearBufferiv(GL_STENCIL, 0, &regs.clear_stencil);
+        } else {
+            zbc_used = true;
+        }
+    }
+
+    if (zbc_used) {
+        LOG_TRACE(Render_OpenGL, "ZBC: Used ZBC clear for efficient buffer clearing");
     }
     ++num_queued_commands;
 }
@@ -1101,7 +1137,7 @@ void RasterizerOpenGL::SyncColorMask() {
         flags[Dirty::ColorMask0] = false;
 
         auto& mask = regs.color_mask[0];
-        glColorMask(mask.R != 0, mask.B != 0, mask.G != 0, mask.A != 0);
+        glColorMask(mask.R != 0, mask.G != 0, mask.B != 0, mask.A != 0);
         return;
     }
 

src/video_core/renderer_opengl/gl_zbc_clear.cpp

@@ -0,0 +1,131 @@
+// SPDX-FileCopyrightText: Copyright 2025 citron Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "video_core/renderer_opengl/gl_zbc_clear.h"
+#include "common/logging/log.h"
+#include "video_core/zbc_manager.h"
+
+#include <glad/glad.h>
+
+namespace OpenGL {
+
+bool ZBCClear::ClearColor(u32 format, u32 type, u32 rt) {
+    const auto zbc_color = VideoCore::ZBCManager::Instance().GetZBCColor(format, type);
+    if (!zbc_color) {
+        LOG_TRACE(Render_OpenGL, "ZBC: No color entry found for format=0x{:X}, type=0x{:X}, using fallback", format, type);
+        return false;
+    }
+
+    const auto clear_color = ConvertColorToOpenGL(*zbc_color);
+
+    LOG_TRACE(Render_OpenGL, "ZBC: Using ZBC clear color for format=0x{:X}, type=0x{:X}, rt={}", format, type, rt);
+    LOG_TRACE(Render_OpenGL, "ZBC: Clear color=[{:.3f}, {:.3f}, {:.3f}, {:.3f}]",
+              clear_color[0], clear_color[1], clear_color[2], clear_color[3]);
+
+    glClearBufferfv(GL_COLOR, rt, clear_color.data());
+    return true;
+}
+
+bool ZBCClear::ClearDepth(u32 format, u32 type) {
+    const auto zbc_depth = VideoCore::ZBCManager::Instance().GetZBCDepth(format, type);
+    if (!zbc_depth) {
+        LOG_TRACE(Render_OpenGL, "ZBC: No depth entry found for format=0x{:X}, type=0x{:X}, using fallback", format, type);
+        return false;
+    }
+
+    const f32 clear_depth = VideoCore::ZBCManager::ConvertDepthToFloat(*zbc_depth);
+
+    LOG_TRACE(Render_OpenGL, "ZBC: Using ZBC clear depth for format=0x{:X}, type=0x{:X}", format, type);
+    LOG_TRACE(Render_OpenGL, "ZBC: Clear depth={:.6f}", clear_depth);
+
+    glClearBufferfv(GL_DEPTH, 0, &clear_depth);
+    return true;
+}
+
+bool ZBCClear::ClearDepthStencil(u32 format, u32 type, u32 stencil_value) {
+    const auto zbc_depth = VideoCore::ZBCManager::Instance().GetZBCDepth(format, type);
+    if (!zbc_depth) {
+        LOG_TRACE(Render_OpenGL, "ZBC: No depth entry found for format=0x{:X}, type=0x{:X}, using fallback", format, type);
+        return false;
+    }
+
+    const f32 clear_depth = VideoCore::ZBCManager::ConvertDepthToFloat(*zbc_depth);
+
+    LOG_TRACE(Render_OpenGL, "ZBC: Using ZBC clear depth-stencil for format=0x{:X}, type=0x{:X}", format, type);
+    LOG_TRACE(Render_OpenGL, "ZBC: Clear depth={:.6f}, stencil={}", clear_depth, stencil_value);
+
+    glClearBufferfi(GL_DEPTH_STENCIL, 0, clear_depth, static_cast<GLint>(stencil_value));
+    return true;
+}
+
+std::optional<std::array<f32, 4>> ZBCClear::GetZBCClearColor(u32 format, u32 type) {
+    const auto zbc_color = VideoCore::ZBCManager::Instance().GetZBCColor(format, type);
+    if (!zbc_color) {
+        return std::nullopt;
+    }
+    return ConvertColorToOpenGL(*zbc_color);
+}
+
+std::optional<f32> ZBCClear::GetZBCClearDepth(u32 format, u32 type) {
+    const auto zbc_depth = VideoCore::ZBCManager::Instance().GetZBCDepth(format, type);
+    if (!zbc_depth) {
+        return std::nullopt;
+    }
+    return VideoCore::ZBCManager::ConvertDepthToFloat(*zbc_depth);
+}
+
+std::array<f32, 4> ZBCClear::ConvertColorToOpenGL(const std::array<u32, 4>& color_u32) {
+    // Convert ZBC color values to OpenGL format
+    // The ZBC color values are typically in RGBA8888 format
+    std::array<f32, 4> color_f32;
+
+    // For now, we'll use the first color value and convert it to RGBA
+    // This might need adjustment based on the actual format used by the game
+    const u32 primary_color = color_u32[0];
+
+    // Extract RGBA components (assuming RGBA8888 format)
+    const u8 r = (primary_color >> 0) & 0xFF;
+    const u8 g = (primary_color >> 8) & 0xFF;
+    const u8 b = (primary_color >> 16) & 0xFF;
+    const u8 a = (primary_color >> 24) & 0xFF;
+
+    // Convert to normalized float values [0.0, 1.0]
+    color_f32[0] = static_cast<f32>(r) / 255.0f; // Red
+    color_f32[1] = static_cast<f32>(g) / 255.0f; // Green
+    color_f32[2] = static_cast<f32>(b) / 255.0f; // Blue
+    color_f32[3] = static_cast<f32>(a) / 255.0f; // Alpha
+
+    // If the color is all zeros, use a default clear color
+    if (color_f32[0] == 0.0f && color_f32[1] == 0.0f &&
+        color_f32[2] == 0.0f && color_f32[3] == 0.0f) {
+        // Use a default clear color (black with full alpha)
+        color_f32 = {0.0f, 0.0f, 0.0f, 1.0f};
+    }
+
+    return color_f32;
+}
+
+bool ZBCClear::ClearStencil(u32 format, u32 type, u32 stencil_value) {
+    // For stencil clearing, we need to check if we have a ZBC entry for stencil type (2)
+    const auto zbc_color = VideoCore::ZBCManager::Instance().GetZBCColor(format, 2);
+    if (!zbc_color) {
+        LOG_TRACE(Render_OpenGL, "ZBC: No stencil entry found for format=0x{:X}, type=0x{:X}, using fallback", format, type);
+        return false;
+    }
+
+    // Convert ZBC color to stencil value
+    // For stencil, we typically use the first component as the stencil value
+    const u32 zbc_stencil = zbc_color.value()[0];
+
+    // Convert to the appropriate stencil format
+    const u32 clear_stencil = zbc_stencil & 0xFF; // Use lower 8 bits for stencil
+
+    LOG_TRACE(Render_OpenGL, "ZBC: Using stencil clear value 0x{:X} for format=0x{:X}", clear_stencil, format);
+
+    // Perform the stencil clear
+    glClearBufferiv(GL_STENCIL, 0, reinterpret_cast<const GLint*>(&clear_stencil));
+
+    return true;
+}
+
+} // namespace OpenGL

src/video_core/renderer_opengl/gl_zbc_clear.h

@@ -0,0 +1,82 @@
+// SPDX-FileCopyrightText: Copyright 2025 citron Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <array>
+#include <optional>
+
+#include "common/common_types.h"
+#include "video_core/zbc_manager.h"
+
+namespace OpenGL {
+
+/**
+ * ZBC-aware buffer clearing for OpenGL renderer
+ *
+ * This class provides efficient buffer clearing operations using ZBC (Zero Bandwidth Clear)
+ * table entries when available, falling back to standard clear operations when needed.
+ */
+class ZBCClear {
+public:
+    /**
+     * Clear color buffer using ZBC if available
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth)
+     * @param rt Render target index
+     * @return True if ZBC clear was used, false if fallback is needed
+     */
+    static bool ClearColor(u32 format, u32 type, u32 rt);
+
+    /**
+     * Clear depth buffer using ZBC if available
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth)
+     * @return True if ZBC clear was used, false if fallback is needed
+     */
+    static bool ClearDepth(u32 format, u32 type);
+
+    /**
+     * Clear depth-stencil buffer using ZBC if available
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth, 2=stencil)
+     * @param stencil_value Stencil clear value
+     * @return True if ZBC clear was used, false if fallback is needed
+     */
+    static bool ClearDepthStencil(u32 format, u32 type, u32 stencil_value);
+
+    /**
+     * Clear stencil buffer using ZBC if available
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth, 2=stencil)
+     * @param stencil_value Stencil clear value
+     * @return True if ZBC clear was used, false if fallback is needed
+     */
+    static bool ClearStencil(u32 format, u32 type, u32 stencil_value);
+
+    /**
+     * Get ZBC clear color for a specific format and type
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth)
+     * @return Optional array of 4 float color values, or nullopt if not available
+     */
+    static std::optional<std::array<f32, 4>> GetZBCClearColor(u32 format, u32 type);
+
+    /**
+     * Get ZBC clear depth for a specific format and type
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth)
+     * @return Optional depth value, or nullopt if not available
+     */
+    static std::optional<f32> GetZBCClearDepth(u32 format, u32 type);
+
+private:
+    /**
+     * Convert ZBC color values to OpenGL format
+     * @param color_u32 Array of 4 uint32 color values
+     * @return Array of 4 float color values for OpenGL
+     */
+    static std::array<f32, 4> ConvertColorToOpenGL(const std::array<u32, 4>& color_u32);
+};
+
+} // namespace OpenGL

src/video_core/renderer_vulkan/blit_image.cpp

@@ -4,6 +4,7 @@
 #include <algorithm>
 
 #include "video_core/renderer_vulkan/vk_texture_cache.h"
+#include "video_core/renderer_vulkan/vk_zbc_clear.h"
 
 #include "common/settings.h"
 #include "video_core/host_shaders/blit_color_float_frag_spv.h"
@@ -592,6 +593,10 @@ void BlitImageHelper::ConvertS8D24ToABGR8(const Framebuffer* dst_framebuffer,
 void BlitImageHelper::ClearColor(const Framebuffer* dst_framebuffer, u8 color_mask,
                                  const std::array<f32, 4>& clear_color,
                                  const Region2D& dst_region) {
+    // Try to use ZBC (Zero Bandwidth Clear) for efficient clearing
+    // Note: We need the format and type from the context, but for now we'll use fallback
+    // TODO: Integrate with proper format/type detection from the rendering context
+
     const BlitImagePipelineKey key{
         .renderpass = dst_framebuffer->RenderPass(),
         .operation = Tegra::Engines::Fermi2D::Operation::BlendPremult,

src/video_core/renderer_vulkan/present/layer.cpp

@@ -35,7 +35,7 @@ VkFormat GetFormat(const Tegra::FramebufferConfig& framebuffer) {
     switch (framebuffer.pixel_format) {
     case Service::android::PixelFormat::Rgba8888:
     case Service::android::PixelFormat::Rgbx8888:
-        return VK_FORMAT_A8B8G8R8_UNORM_PACK32;
+        return VK_FORMAT_R8G8B8A8_UNORM;
     case Service::android::PixelFormat::Rgb565:
         return VK_FORMAT_R5G6B5_UNORM_PACK16;
     case Service::android::PixelFormat::Bgra8888:
@@ -43,7 +43,7 @@ VkFormat GetFormat(const Tegra::FramebufferConfig& framebuffer) {
     default:
         UNIMPLEMENTED_MSG("Unknown framebuffer pixel format: {}",
                           static_cast<u32>(framebuffer.pixel_format));
-        return VK_FORMAT_A8B8G8R8_UNORM_PACK32;
+        return VK_FORMAT_R8G8B8A8_UNORM;
     }
 }
 

src/video_core/renderer_vulkan/vk_zbc_clear.cpp

@@ -0,0 +1,172 @@
+// SPDX-FileCopyrightText: Copyright 2025 citron Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "video_core/renderer_vulkan/vk_zbc_clear.h"
+#include "common/logging/log.h"
+#include "video_core/zbc_manager.h"
+
+namespace Vulkan {
+
+bool ZBCClear::ClearColorImage(vk::CommandBuffer& cmdbuf, VkImage image, VkImageLayout layout,
+                              u32 format, u32 type) {
+    const auto zbc_color = VideoCore::ZBCManager::Instance().GetZBCColor(format, type);
+    if (!zbc_color) {
+        LOG_TRACE(Render_Vulkan, "ZBC: No color entry found for format=0x{:X}, type=0x{:X}, using fallback", format, type);
+        return false;
+    }
+
+    const VkClearColorValue clear_color = ConvertColorToVulkan(*zbc_color);
+
+    LOG_TRACE(Render_Vulkan, "ZBC: Using ZBC clear color for format=0x{:X}, type=0x{:X}", format, type);
+    LOG_TRACE(Render_Vulkan, "ZBC: Clear color=[{:.3f}, {:.3f}, {:.3f}, {:.3f}]",
+              clear_color.float32[0], clear_color.float32[1], clear_color.float32[2], clear_color.float32[3]);
+
+    static constexpr std::array<VkImageSubresourceRange, 1> subresources{{{
+        .aspectMask = VK_IMAGE_ASPECT_COLOR_BIT,
+        .baseMipLevel = 0,
+        .levelCount = 1,
+        .baseArrayLayer = 0,
+        .layerCount = 1,
+    }}};
+
+    cmdbuf.ClearColorImage(image, layout, clear_color, subresources);
+    return true;
+}
+
+bool ZBCClear::ClearDepthStencilImage(vk::CommandBuffer& cmdbuf, VkImage image, VkImageLayout layout,
+                                     u32 format, u32 type, u32 stencil_value) {
+    const auto zbc_depth = VideoCore::ZBCManager::Instance().GetZBCDepth(format, type);
+    if (!zbc_depth) {
+        LOG_TRACE(Render_Vulkan, "ZBC: No depth entry found for format=0x{:X}, type=0x{:X}, using fallback", format, type);
+        return false;
+    }
+
+    const f32 clear_depth = VideoCore::ZBCManager::ConvertDepthToFloat(*zbc_depth);
+
+    LOG_TRACE(Render_Vulkan, "ZBC: Using ZBC clear depth-stencil for format=0x{:X}, type=0x{:X}", format, type);
+    LOG_TRACE(Render_Vulkan, "ZBC: Clear depth={:.6f}, stencil={}", clear_depth, stencil_value);
+
+    const VkClearDepthStencilValue clear_value{
+        .depth = clear_depth,
+        .stencil = stencil_value,
+    };
+
+
+    // Use ClearAttachments for depth-stencil clearing
+    const VkClearValue clear_value_union{
+        .depthStencil = clear_value,
+    };
+
+    const VkClearAttachment attachment{
+        .aspectMask = VK_IMAGE_ASPECT_DEPTH_BIT | VK_IMAGE_ASPECT_STENCIL_BIT,
+        .colorAttachment = 0,
+        .clearValue = clear_value_union,
+    };
+
+    const VkClearRect clear_rect{
+        .rect = {{0, 0}, {0xFFFFFFFF, 0xFFFFFFFF}}, // Clear entire image
+        .baseArrayLayer = 0,
+        .layerCount = 1,
+    };
+
+    cmdbuf.ClearAttachments({attachment}, {clear_rect});
+    return true;
+}
+
+std::optional<VkClearColorValue> ZBCClear::GetZBCClearColor(u32 format, u32 type) {
+    const auto zbc_color = VideoCore::ZBCManager::Instance().GetZBCColor(format, type);
+    if (!zbc_color) {
+        return std::nullopt;
+    }
+    return ConvertColorToVulkan(*zbc_color);
+}
+
+std::optional<f32> ZBCClear::GetZBCClearDepth(u32 format, u32 type) {
+    const auto zbc_depth = VideoCore::ZBCManager::Instance().GetZBCDepth(format, type);
+    if (!zbc_depth) {
+        return std::nullopt;
+    }
+    return VideoCore::ZBCManager::ConvertDepthToFloat(*zbc_depth);
+}
+
+VkClearColorValue ZBCClear::ConvertColorToVulkan(const std::array<u32, 4>& color_u32) {
+    // Convert ZBC color values to Vulkan format
+    // The ZBC color values are typically in RGBA8888 format
+    VkClearColorValue clear_color{};
+
+    // For now, we'll use the first color value and convert it to RGBA
+    // This might need adjustment based on the actual format used by the game
+    const u32 primary_color = color_u32[0];
+
+    // Extract RGBA components (assuming RGBA8888 format)
+    const u8 r = (primary_color >> 0) & 0xFF;
+    const u8 g = (primary_color >> 8) & 0xFF;
+    const u8 b = (primary_color >> 16) & 0xFF;
+    const u8 a = (primary_color >> 24) & 0xFF;
+
+    // Convert to normalized float values [0.0, 1.0]
+    clear_color.float32[0] = static_cast<f32>(r) / 255.0f; // Red
+    clear_color.float32[1] = static_cast<f32>(g) / 255.0f; // Green
+    clear_color.float32[2] = static_cast<f32>(b) / 255.0f; // Blue
+    clear_color.float32[3] = static_cast<f32>(a) / 255.0f; // Alpha
+
+    // If the color is all zeros, use a default clear color
+    if (clear_color.float32[0] == 0.0f && clear_color.float32[1] == 0.0f &&
+        clear_color.float32[2] == 0.0f && clear_color.float32[3] == 0.0f) {
+        // Use a default clear color (black with full alpha)
+        clear_color.float32[0] = 0.0f; // Red
+        clear_color.float32[1] = 0.0f; // Green
+        clear_color.float32[2] = 0.0f; // Blue
+        clear_color.float32[3] = 1.0f; // Alpha
+    }
+
+    return clear_color;
+}
+
+bool ZBCClear::ClearStencilImage(vk::CommandBuffer& cmdbuf, VkImage image, VkImageLayout layout,
+                                 u32 format, u32 type, u32 stencil_value) {
+    // For stencil clearing, we need to check if we have a ZBC entry for stencil type (2)
+    const auto zbc_color = VideoCore::ZBCManager::Instance().GetZBCColor(format, 2);
+    if (!zbc_color) {
+        LOG_TRACE(Render_Vulkan, "ZBC: No stencil entry found for format=0x{:X}, type=0x{:X}, using fallback", format, type);
+        return false;
+    }
+
+    // Convert ZBC color to stencil value
+    // For stencil, we typically use the first component as the stencil value
+    const u32 zbc_stencil = zbc_color.value()[0];
+
+    // Convert to the appropriate stencil format
+    const u32 clear_stencil = zbc_stencil & 0xFF; // Use lower 8 bits for stencil
+
+    LOG_TRACE(Render_Vulkan, "ZBC: Using stencil clear value 0x{:X} for format=0x{:X}", clear_stencil, format);
+
+    // Create clear value for stencil
+    const VkClearDepthStencilValue clear_value{
+        .depth = 1.0f, // Default depth value
+        .stencil = clear_stencil,
+    };
+
+    // Use ClearAttachments for stencil clearing
+    const VkClearValue clear_value_union{
+        .depthStencil = clear_value,
+    };
+
+    const VkClearAttachment attachment{
+        .aspectMask = VK_IMAGE_ASPECT_STENCIL_BIT,
+        .colorAttachment = 0,
+        .clearValue = clear_value_union,
+    };
+
+    const VkClearRect clear_rect{
+        .rect = {{0, 0}, {0xFFFFFFFF, 0xFFFFFFFF}}, // Clear entire image
+        .baseArrayLayer = 0,
+        .layerCount = 1,
+    };
+
+    cmdbuf.ClearAttachments({attachment}, {clear_rect});
+
+    return true;
+}
+
+} // namespace Vulkan

src/video_core/renderer_vulkan/vk_zbc_clear.h

@@ -0,0 +1,86 @@
+// SPDX-FileCopyrightText: Copyright 2025 citron Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <array>
+#include <optional>
+
+#include "common/common_types.h"
+#include "video_core/vulkan_common/vulkan_wrapper.h"
+#include "video_core/zbc_manager.h"
+
+namespace Vulkan {
+
+/**
+ * ZBC-aware buffer clearing for Vulkan renderer
+ *
+ * This class provides efficient buffer clearing operations using ZBC (Zero Bandwidth Clear)
+ * table entries when available, falling back to standard clear operations when needed.
+ */
+class ZBCClear {
+public:
+    /**
+     * Clear color image using ZBC if available
+     * @param cmdbuf Vulkan command buffer
+     * @param image Image to clear
+     * @param layout Current image layout
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth)
+     * @return True if ZBC clear was used, false if fallback is needed
+     */
+    static bool ClearColorImage(vk::CommandBuffer& cmdbuf, VkImage image, VkImageLayout layout,
+                               u32 format, u32 type);
+
+    /**
+     * Clear depth-stencil image using ZBC if available
+     * @param cmdbuf Vulkan command buffer
+     * @param image Image to clear
+     * @param layout Current image layout
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth, 2=stencil)
+     * @param stencil_value Stencil clear value
+     * @return True if ZBC clear was used, false if fallback is needed
+     */
+    static bool ClearDepthStencilImage(vk::CommandBuffer& cmdbuf, VkImage image, VkImageLayout layout,
+                                      u32 format, u32 type, u32 stencil_value);
+
+    /**
+     * Clear stencil image using ZBC if available
+     * @param cmdbuf Vulkan command buffer
+     * @param image Image to clear
+     * @param layout Current image layout
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth, 2=stencil)
+     * @param stencil_value Stencil clear value
+     * @return True if ZBC clear was used, false if fallback is needed
+     */
+    static bool ClearStencilImage(vk::CommandBuffer& cmdbuf, VkImage image, VkImageLayout layout,
+                                 u32 format, u32 type, u32 stencil_value);
+
+    /**
+     * Get ZBC clear color for a specific format and type
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth)
+     * @return Optional VkClearColorValue, or nullopt if not available
+     */
+    static std::optional<VkClearColorValue> GetZBCClearColor(u32 format, u32 type);
+
+    /**
+     * Get ZBC clear depth for a specific format and type
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth)
+     * @return Optional depth value, or nullopt if not available
+     */
+    static std::optional<f32> GetZBCClearDepth(u32 format, u32 type);
+
+private:
+    /**
+     * Convert ZBC color values to Vulkan format
+     * @param color_u32 Array of 4 uint32 color values
+     * @return VkClearColorValue for Vulkan
+     */
+    static VkClearColorValue ConvertColorToVulkan(const std::array<u32, 4>& color_u32);
+};
+
+} // namespace Vulkan

src/video_core/zbc_manager.cpp

@@ -0,0 +1,124 @@
+// SPDX-FileCopyrightText: Copyright 2025 citron Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "video_core/zbc_manager.h"
+#include "common/logging/log.h"
+
+namespace VideoCore {
+
+std::optional<std::array<u32, 4>> ZBCManager::GetZBCColor(u32 format, u32 type) const {
+    std::scoped_lock lock{zbc_table_mutex};
+    const auto key = std::make_pair(format, type);
+    const auto it = zbc_table.find(key);
+    if (it != zbc_table.end()) {
+        LOG_TRACE(Service_NVDRV, "ZBC: Retrieved color for format=0x{:X}, type=0x{:X}", format, type);
+        return it->second.color_ds;
+    }
+    LOG_TRACE(Service_NVDRV, "ZBC: No color entry found for format=0x{:X}, type=0x{:X}", format, type);
+    return std::nullopt;
+}
+
+std::optional<u32> ZBCManager::GetZBCDepth(u32 format, u32 type) const {
+    std::scoped_lock lock{zbc_table_mutex};
+    const auto key = std::make_pair(format, type);
+    const auto it = zbc_table.find(key);
+    if (it != zbc_table.end()) {
+        LOG_TRACE(Service_NVDRV, "ZBC: Retrieved depth for format=0x{:X}, type=0x{:X}", format, type);
+        return it->second.depth;
+    }
+    LOG_TRACE(Service_NVDRV, "ZBC: No depth entry found for format=0x{:X}, type=0x{:X}", format, type);
+    return std::nullopt;
+}
+
+void ZBCManager::StoreZBCEntry(u32 format, u32 type, const std::array<u32, 4>& color_ds,
+                               const std::array<u32, 4>& color_l2, u32 depth) {
+    std::scoped_lock lock{zbc_table_mutex};
+
+    ZBCEntry entry;
+    entry.color_ds = color_ds;
+    entry.color_l2 = color_l2;
+    entry.depth = depth;
+    entry.format = format;
+    entry.type = type;
+    entry.ref_count = 1;
+
+    const auto key = std::make_pair(format, type);
+    zbc_table[key] = entry;
+
+    LOG_DEBUG(Service_NVDRV, "ZBC: Stored entry format=0x{:X}, type=0x{:X}, depth=0x{:X}",
+              format, type, depth);
+    LOG_TRACE(Service_NVDRV, "ZBC: color_ds=[0x{:08X}, 0x{:08X}, 0x{:08X}, 0x{:08X}]",
+              color_ds[0], color_ds[1], color_ds[2], color_ds[3]);
+    LOG_TRACE(Service_NVDRV, "ZBC: color_l2=[0x{:08X}, 0x{:08X}, 0x{:08X}, 0x{:08X}]",
+              color_l2[0], color_l2[1], color_l2[2], color_l2[3]);
+}
+
+std::array<f32, 4> ZBCManager::ConvertToFloat(const std::array<u32, 4>& color_u32) {
+    std::array<f32, 4> color_f32;
+
+    // Convert from packed RGBA format to normalized float values
+    // Assuming the color values are in RGBA8888 format
+    for (size_t i = 0; i < 4; ++i) {
+        const u32 packed = color_u32[i];
+
+        // Extract RGBA components (assuming RGBA8888 format)
+        const u8 r = (packed >> 0) & 0xFF;
+        const u8 g = (packed >> 8) & 0xFF;
+        const u8 b = (packed >> 16) & 0xFF;
+        const u8 a = (packed >> 24) & 0xFF;
+
+        // Convert to normalized float values [0.0, 1.0]
+        color_f32[0] = static_cast<f32>(r) / 255.0f; // Red
+        color_f32[1] = static_cast<f32>(g) / 255.0f; // Green
+        color_f32[2] = static_cast<f32>(b) / 255.0f; // Blue
+        color_f32[3] = static_cast<f32>(a) / 255.0f; // Alpha
+
+        // For now, we'll use the first component as the primary color
+        // This might need adjustment based on the actual format used
+        break;
+    }
+
+    // If we only have one component, replicate it for RGBA
+    if (color_f32[0] == 0.0f && color_f32[1] == 0.0f &&
+        color_f32[2] == 0.0f && color_f32[3] == 0.0f) {
+        // Fallback: use the first uint32 as a single color value
+        const u32 first_color = color_u32[0];
+        const f32 normalized = static_cast<f32>(first_color) / static_cast<f32>(0xFFFFFFFF);
+        color_f32 = {normalized, normalized, normalized, 1.0f};
+    }
+
+    return color_f32;
+}
+
+f32 ZBCManager::ConvertDepthToFloat(u32 depth_u32) {
+    // Convert depth value to normalized float [0.0, 1.0]
+    // This assumes 32-bit depth format
+    return static_cast<f32>(depth_u32) / static_cast<f32>(0xFFFFFFFF);
+}
+
+bool ZBCManager::HasZBCEntry(u32 format, u32 type) const {
+    std::scoped_lock lock{zbc_table_mutex};
+    const auto key = std::make_pair(format, type);
+    return zbc_table.find(key) != zbc_table.end();
+}
+
+bool ZBCManager::RemoveZBCEntry(u32 format, u32 type) {
+    std::scoped_lock lock{zbc_table_mutex};
+    const auto key = std::make_pair(format, type);
+    const auto it = zbc_table.find(key);
+    if (it != zbc_table.end()) {
+        zbc_table.erase(it);
+        LOG_DEBUG(Service_NVDRV, "ZBC: Removed entry format=0x{:X}, type=0x{:X}", format, type);
+        return true;
+    }
+    return false;
+}
+
+void ZBCManager::ClearAllEntries() {
+    std::scoped_lock lock{zbc_table_mutex};
+    const size_t count = zbc_table.size();
+    zbc_table.clear();
+    LOG_DEBUG(Service_NVDRV, "ZBC: Cleared all {} entries", count);
+}
+
+} // namespace VideoCore

src/video_core/zbc_manager.h

@@ -0,0 +1,111 @@
+// SPDX-FileCopyrightText: Copyright 2025 citron Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <array>
+#include <optional>
+#include <mutex>
+#include <map>
+
+#include "common/common_types.h"
+
+namespace VideoCore {
+
+/**
+ * ZBC (Zero Bandwidth Clear) Manager for efficient GPU buffer clearing operations
+ *
+ * This class manages ZBC table entries that store pre-defined clear colors and depth values
+ * for efficient buffer clearing operations. It integrates with the GPU rendering pipeline
+ * to provide optimized clear operations without requiring bandwidth for clear values.
+ */
+class ZBCManager {
+public:
+    static ZBCManager& Instance() {
+        static ZBCManager instance;
+        return instance;
+    }
+
+    // ZBC table entry structure
+    struct ZBCEntry {
+        std::array<u32, 4> color_ds;  // Direct Surface color values
+        std::array<u32, 4> color_l2;  // L2 cache color values
+        u32 depth;                    // Depth clear value
+        u32 format;                   // Surface format
+        u32 type;                     // Clear type (0=color, 1=depth)
+        u32 ref_count;                // Reference count for cleanup
+    };
+
+    /**
+     * Get ZBC color values for a specific format and type
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth)
+     * @return Optional array of 4 color values, or nullopt if not found
+     */
+    std::optional<std::array<u32, 4>> GetZBCColor(u32 format, u32 type) const;
+
+    /**
+     * Get ZBC depth value for a specific format and type
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth)
+     * @return Optional depth value, or nullopt if not found
+     */
+    std::optional<u32> GetZBCDepth(u32 format, u32 type) const;
+
+    /**
+     * Store ZBC entry in the table
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth)
+     * @param color_ds Direct Surface color values
+     * @param color_l2 L2 cache color values
+     * @param depth Depth clear value
+     */
+    void StoreZBCEntry(u32 format, u32 type, const std::array<u32, 4>& color_ds,
+                       const std::array<u32, 4>& color_l2, u32 depth);
+
+    /**
+     * Convert ZBC color values to floating point for OpenGL/Vulkan
+     * @param color_u32 Array of 4 uint32 color values
+     * @return Array of 4 float color values normalized to [0,1]
+     */
+    static std::array<f32, 4> ConvertToFloat(const std::array<u32, 4>& color_u32);
+
+    /**
+     * Convert ZBC depth value to floating point
+     * @param depth_u32 Depth value as uint32
+     * @return Depth value as float normalized to [0,1]
+     */
+    static f32 ConvertDepthToFloat(u32 depth_u32);
+
+    /**
+     * Check if ZBC entry exists for given format and type
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth)
+     * @return True if entry exists, false otherwise
+     */
+    bool HasZBCEntry(u32 format, u32 type) const;
+
+    /**
+     * Remove ZBC entry from table
+     * @param format Surface format identifier
+     * @param type Clear type (0=color, 1=depth)
+     * @return True if entry was removed, false if not found
+     */
+    bool RemoveZBCEntry(u32 format, u32 type);
+
+    /**
+     * Clear all ZBC entries
+     */
+    void ClearAllEntries();
+
+private:
+    ZBCManager() = default;
+    ~ZBCManager() = default;
+    ZBCManager(const ZBCManager&) = delete;
+    ZBCManager& operator=(const ZBCManager&) = delete;
+
+    mutable std::mutex zbc_table_mutex;
+    std::map<std::pair<u32, u32>, ZBCEntry> zbc_table; // Key: (format, type)
+};
+
+} // namespace VideoCore