Made pipelines create a second pipeline for offscreen rener of g_buffers

env

@@ -0,0 +1 @@
+MVK_CONFIG_USE_METAL_ARGUMENT_BUFFERS=1

shader_src/g_pos.frag

@@ -0,0 +1,4 @@
+#version 450
+
+void main() {
+}

shader_src/g_pos.vert

@@ -0,0 +1,4 @@
+#version 450
+
+void main() {
+}

src/main.c

@@ -111,11 +111,7 @@ typedef struct GraphicsPipelineInfoStruct {
 
   VkDescriptorSetLayoutCreateInfo descriptor_info;
 
-  uint32_t                         input_bindings_count;
-  VkVertexInputBindingDescription* input_bindings;
-
-  uint32_t                           input_attributes_count;
-  VkVertexInputAttributeDescription* input_attributes;
+  VkPipelineVertexInputStateCreateInfo input_info;
 
   uint32_t shader_stages_count;
   VkPipelineShaderStageCreateInfo* shader_stages;
@@ -131,6 +127,7 @@ typedef struct GraphicsPipelineStruct {
 
   VkPipelineLayout      layout;
   VkPipeline            pipeline;
+  VkPipeline            offscreen_pipeline;
 } GraphicsPipeline;
 
 typedef struct VulkanContextStruct {
@@ -184,9 +181,11 @@ typedef struct VulkanContextStruct {
   uint32_t max_frames_in_flight;
 
   // Per frame objects
+  VkCommandBuffer* offscreen_command_buffers;
   VkCommandBuffer* swapchain_command_buffers;
   VkSemaphore* image_available_semaphores;
   VkSemaphore* render_finished_semaphores;
+  VkSemaphore* offscreen_complete_semaphores;
   VkFence* in_flight_fences;
 
   VkRenderPass render_pass;
@@ -220,10 +219,6 @@ struct Vertex {
   vec3 color;
 };
 
-struct ModelUBO {
-  mat4 model;
-};
-
 struct SceneUBO {
   mat4 test;
 };
@@ -1397,13 +1392,12 @@ void command_draw_object(Object object, VkCommandBuffer command_buffer) {
   vkCmdDrawIndexed(command_buffer, mesh->index_count, 1, 0, 0, 0);
 }
 
-void command_draw_pipeline(GraphicsPipeline pipeline, uint32_t object_count, Object* objects, uint32_t frame_num, VkDescriptorSet* scene_descriptors, struct ScenePC* scene_constants, VkDeviceAddress object_buffer_addr, VkCommandBuffer command_buffer) {
-  vkCmdBindPipeline(command_buffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline.pipeline);
-  vkCmdPushConstants(command_buffer, pipeline.layout, VK_SHADER_STAGE_VERTEX_BIT, 0, sizeof(struct ScenePC), scene_constants);
-  vkCmdPushConstants(command_buffer, pipeline.layout, VK_SHADER_STAGE_VERTEX_BIT, sizeof(struct ScenePC), sizeof(VkDeviceAddress), &object_buffer_addr);
-
-  // Bind the scene descriptor
-  vkCmdBindDescriptorSets(command_buffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline.layout, 0, 1, &scene_descriptors[frame_num], 0, 0);
+void command_draw_pipeline(GraphicsPipeline pipeline, uint32_t object_count, Object* objects, uint32_t frame_num, VkCommandBuffer command_buffer, int offscreen) {
+  if(offscreen) {
+    vkCmdBindPipeline(command_buffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline.offscreen_pipeline);
+  } else {
+    vkCmdBindPipeline(command_buffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline.pipeline);
+  }
 
   if(pipeline.descriptors != NULL) {
     vkCmdBindDescriptorSets(command_buffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline.layout, 1, 1, &pipeline.descriptors[frame_num], 0, 0);
@@ -1414,7 +1408,39 @@ void command_draw_pipeline(GraphicsPipeline pipeline, uint32_t object_count, Obj
   }
 }
 
-VkResult command_draw_scene(uint32_t pipelines_count, GraphicsPipeline* pipelines, uint32_t* object_counts, Object** objects, uint32_t frame_num, VkDescriptorSet* scene_descriptors, struct ScenePC* scene_constants, VkCommandBuffer command_buffer, VkRenderPass render_pass, VkFramebuffer framebuffer, VkExtent2D extent, VkDeviceAddress object_buffer_addr) {
+// Setup a scene for vkCmdDrawIndexedIndirect
+// Before the call is made the following needs to be ready:
+// 1) Vertex data for entire scene in one vertex buffer
+// 2) Index data for entire scene in one index buffer
+// 3) Descriptor data in single descriptor set
+//   a) e.x. all textures for the draw call need to be in the bound pipeline descriptor set
+// 4) Object Data populated per-instance into buffer which will be pushed by VkDeviceAddress
+// 5) Buffer of draw command ordered by instance id(first is 0, increase by 1 every 'stride')
+//
+// Once that is setup, the call to vkCmdDrawIndexed will happen and then:
+// 1) For each draw command read from the command buffer
+//   a) Consume the indices/vertices to run the vertex shaders
+//     i) Vertex shaders access the per-instance object data indexed by gl_instanceID
+//     ii) This object data can have indices for other descriptors
+//       x) e.x. a shader can read object data with int Z that tell it to use a sampler at binding Z
+//
+// If I want to start by not worrying about dynamic object load/unload then I can create the above buffers
+// when loading the scene, and free them all at once
+//
+// If I want to start worrying about loading/unloading then I need to find a way to efficiently reconstruct
+// these buffers on changes
+// Ideas:
+//  - Mark objects as 'deleted' to cheaply cull during a compute cull/vertex shader
+//    - Would require only a 1-bit change per deletion
+//    - Would require defragmentation periodically(or whenever trying to add without space)
+
+VkResult create_scene(){
+  
+
+  return VK_SUCCESS;
+}
+
+VkResult command_draw_scene(uint32_t pipelines_count, GraphicsPipeline* pipelines, uint32_t* object_counts, Object** objects, uint32_t frame_num, VkDescriptorSet* scene_descriptors, struct ScenePC* scene_constants, VkCommandBuffer command_buffer, VkRenderPass render_pass, VkFramebuffer framebuffer, VkExtent2D extent, VkDeviceAddress object_buffer_addr, int offscreen) {
   VkCommandBufferBeginInfo begin_info = {
     .sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO,
     .flags = 0,
@@ -1473,8 +1499,14 @@ VkResult command_draw_scene(uint32_t pipelines_count, GraphicsPipeline* pipeline
   };
   vkCmdSetScissor(command_buffer, 0, 1, &scissor);
 
+  vkCmdPushConstants(command_buffer, pipelines[0].layout, VK_SHADER_STAGE_VERTEX_BIT, 0, sizeof(struct ScenePC), scene_constants);
+  vkCmdPushConstants(command_buffer, pipelines[0].layout, VK_SHADER_STAGE_VERTEX_BIT, sizeof(struct ScenePC), sizeof(VkDeviceAddress), &object_buffer_addr);
+
+  // Bind the scene descriptor
+  vkCmdBindDescriptorSets(command_buffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipelines[0].layout, 0, 1, &scene_descriptors[frame_num], 0, 0);
+
   for(uint i = 0; i < pipelines_count; i++) {
-    command_draw_pipeline(pipelines[i], object_counts[i], objects[i], frame_num, scene_descriptors, scene_constants, object_buffer_addr, command_buffer);
+    command_draw_pipeline(pipelines[i], object_counts[i], objects[i], frame_num, command_buffer, offscreen);
   }
 
   vkCmdEndRenderPass(command_buffer);
@@ -1575,7 +1607,8 @@ Object create_renderable(Mesh* mesh, GraphicsPipeline* pipeline) {
 VkResult create_graphics_pipeline(
     VkDevice device,
     VkExtent2D extent,
-    VkRenderPass render_pass,
+    VkRenderPass draw_render_pass,
+    VkRenderPass offscreen_render_pass,
     GraphicsPipelineInfo pipeline_info,
     uint32_t max_frames_in_flight,
     GraphicsPipeline* out
@@ -1685,14 +1718,6 @@ VkResult create_graphics_pipeline(
     .pDynamicStates = dynamic_states,
   };
 
-  VkPipelineVertexInputStateCreateInfo vertex_input_info = {
-    .sType = VK_STRUCTURE_TYPE_PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO,
-    .vertexBindingDescriptionCount = pipeline_info.input_bindings_count,
-    .pVertexBindingDescriptions = pipeline_info.input_bindings,
-    .vertexAttributeDescriptionCount = pipeline_info.input_attributes_count,
-    .pVertexAttributeDescriptions = pipeline_info.input_attributes,
-  };
-
   VkPipelineInputAssemblyStateCreateInfo input_assembly_info = {
     .sType = VK_STRUCTURE_TYPE_PIPELINE_INPUT_ASSEMBLY_STATE_CREATE_INFO,
     .topology = VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST,
@@ -1784,11 +1809,11 @@ VkResult create_graphics_pipeline(
     .blendConstants[3] = 0.0f,
   };
 
-  VkGraphicsPipelineCreateInfo info = {
+  VkGraphicsPipelineCreateInfo draw_pipeline_info = {
     .sType = VK_STRUCTURE_TYPE_GRAPHICS_PIPELINE_CREATE_INFO,
     .stageCount = pipeline_info.shader_stages_count,
     .pStages = pipeline_info.shader_stages,
-    .pVertexInputState = &vertex_input_info,
+    .pVertexInputState = &pipeline_info.input_info,
     .pInputAssemblyState = &input_assembly_info,
     .pViewportState = &viewport_state,
     .pRasterizationState = &raster_info,
@@ -1797,13 +1822,56 @@ VkResult create_graphics_pipeline(
     .pDepthStencilState = &depth_info,
     .pMultisampleState = &multisample_info,
     .layout = out->layout,
-    .renderPass = render_pass,
+    .renderPass = draw_render_pass,
     .subpass = 0,
     .basePipelineHandle = VK_NULL_HANDLE,
     .basePipelineIndex = -1,
   };
 
-  result = vkCreateGraphicsPipelines(device, VK_NULL_HANDLE, 1, &info, 0, &out->pipeline);
+  VkPipelineColorBlendAttachmentState offscreen_attachment_states[] = {
+    {
+      .colorWriteMask = VK_COLOR_COMPONENT_R_BIT | VK_COLOR_COMPONENT_G_BIT | VK_COLOR_COMPONENT_B_BIT | VK_COLOR_COMPONENT_A_BIT,
+      .blendEnable = VK_FALSE,
+    },
+  };
+
+  VkPipelineColorBlendStateCreateInfo offscreen_blend_info = {
+    .sType = VK_STRUCTURE_TYPE_PIPELINE_COLOR_BLEND_STATE_CREATE_INFO,
+    .logicOpEnable = VK_FALSE,
+    .logicOp = VK_LOGIC_OP_COPY,
+    .attachmentCount = sizeof(offscreen_attachment_states)/sizeof(VkPipelineColorBlendAttachmentState),
+    .pAttachments = offscreen_attachment_states,
+    .blendConstants[0] = 0.0f,
+    .blendConstants[1] = 0.0f,
+    .blendConstants[2] = 0.0f,
+    .blendConstants[3] = 0.0f,
+  };
+
+  VkGraphicsPipelineCreateInfo offscreen_pipeline_info = {
+    .sType = VK_STRUCTURE_TYPE_GRAPHICS_PIPELINE_CREATE_INFO,
+    .stageCount = pipeline_info.shader_stages_count,
+    .pStages = pipeline_info.shader_stages, // TODO: offscreen stages
+    .pVertexInputState = &pipeline_info.input_info,
+    .pInputAssemblyState = &input_assembly_info,
+    .pViewportState = &viewport_state,
+    .pRasterizationState = &raster_info,
+    .pColorBlendState = &offscreen_blend_info,
+    .pDynamicState = &dynamic_info,
+    .pDepthStencilState = &depth_info,
+    .pMultisampleState = &multisample_info,
+    .layout = out->layout,
+    .renderPass = offscreen_render_pass,
+    .subpass = 0,
+    .basePipelineHandle = VK_NULL_HANDLE,
+    .basePipelineIndex = -1,
+  };
+
+  result = vkCreateGraphicsPipelines(device, VK_NULL_HANDLE, 1, &draw_pipeline_info, 0, &out->pipeline);
+  if(result != VK_SUCCESS) {
+    return result;
+  }
+
+  result = vkCreateGraphicsPipelines(device, VK_NULL_HANDLE, 1, &offscreen_pipeline_info, 0, &out->offscreen_pipeline);
   if(result != VK_SUCCESS) {
     return result;
   }
@@ -1811,7 +1879,7 @@ VkResult create_graphics_pipeline(
   return VK_SUCCESS;
 }
 
-VkResult create_simple_mesh_pipeline(VkDevice device, VkExtent2D extent, VkRenderPass render_pass, VkDescriptorSetLayout scene_layout, uint32_t max_frames_in_flight, GraphicsPipeline* out) {
+VkResult create_simple_mesh_pipeline(VkDevice device, VkExtent2D extent, VkRenderPass render_pass, VkRenderPass offscreen_render_pass, VkDescriptorSetLayout scene_layout, uint32_t max_frames_in_flight, GraphicsPipeline* out) {
   if(out == NULL) {
     return VK_ERROR_VALIDATION_FAILED_EXT;
   }
@@ -1873,21 +1941,26 @@ VkResult create_simple_mesh_pipeline(VkDevice device, VkExtent2D extent, VkRende
     .pNext = NULL,
   };
 
+  VkPipelineVertexInputStateCreateInfo input_info = {
+    .sType = VK_STRUCTURE_TYPE_PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO,
+    .pVertexBindingDescriptions = bindings,
+    .vertexBindingDescriptionCount = sizeof(bindings)/sizeof(VkVertexInputBindingDescription),
+    .pVertexAttributeDescriptions = attributes,
+    .vertexAttributeDescriptionCount = sizeof(attributes)/sizeof(VkVertexInputAttributeDescription),
+  };
+
   GraphicsPipelineInfo pipeline_info = {
     .descriptor_info = set_info,
     .shader_stages_count = sizeof(shader_stages)/sizeof(VkPipelineShaderStageCreateInfo),
     .shader_stages = shader_stages,
     .scene_layout = scene_layout,
-    .input_bindings = bindings,
-    .input_bindings_count = sizeof(bindings)/sizeof(VkVertexInputBindingDescription),
-    .input_attributes = attributes,
-    .input_attributes_count = sizeof(attributes)/sizeof(VkVertexInputAttributeDescription),
+    .input_info = input_info,
   };
 
-  return create_graphics_pipeline(device, extent, render_pass, pipeline_info, max_frames_in_flight, out);
+  return create_graphics_pipeline(device, extent, render_pass, offscreen_render_pass, pipeline_info, max_frames_in_flight, out);
 }
 
-VkResult create_texture_mesh_pipeline(VkDevice device, VkPhysicalDeviceMemoryProperties memories, VkExtent2D extent, VkRenderPass render_pass, VkDescriptorSetLayout scene_layout, uint32_t max_frames_in_flight, VkCommandPool transfer_pool, VkQueue transfer_queue, VkQueue graphics_queue, VkCommandPool graphics_pool, uint32_t transfer_family, uint32_t graphics_family, GraphicsPipeline* out) {
+VkResult create_texture_mesh_pipeline(VkDevice device, VkPhysicalDeviceMemoryProperties memories, VkExtent2D extent, VkRenderPass render_pass, VkRenderPass offscreen_render_pass, VkDescriptorSetLayout scene_layout, uint32_t max_frames_in_flight, VkCommandPool transfer_pool, VkQueue transfer_queue, VkQueue graphics_queue, VkCommandPool graphics_pool, uint32_t transfer_family, uint32_t graphics_family, GraphicsPipeline* out) {
   if(out == NULL) {
     return VK_ERROR_VALIDATION_FAILED_EXT;
   }
@@ -1968,15 +2041,20 @@ VkResult create_texture_mesh_pipeline(VkDevice device, VkPhysicalDeviceMemoryPro
     .pNext = &set_flags_info,
   };
 
+  VkPipelineVertexInputStateCreateInfo input_info = {
+    .sType = VK_STRUCTURE_TYPE_PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO,
+    .pVertexBindingDescriptions = bindings,
+    .vertexBindingDescriptionCount = sizeof(bindings)/sizeof(VkVertexInputBindingDescription),
+    .pVertexAttributeDescriptions = attributes,
+    .vertexAttributeDescriptionCount = sizeof(attributes)/sizeof(VkVertexInputAttributeDescription),
+  };
+
   GraphicsPipelineInfo pipeline_info = {
     .descriptor_info = set_info,
     .shader_stages_count = sizeof(shader_stages)/sizeof(VkPipelineShaderStageCreateInfo),
     .shader_stages = shader_stages,
     .scene_layout = scene_layout,
-    .input_bindings = bindings,
-    .input_bindings_count = sizeof(bindings)/sizeof(VkVertexInputBindingDescription),
-    .input_attributes = attributes,
-    .input_attributes_count = sizeof(attributes)/sizeof(VkVertexInputAttributeDescription),
+    .input_info = input_info,
   };
 
   GPUPage* memory = NULL;
@@ -1985,7 +2063,7 @@ VkResult create_texture_mesh_pipeline(VkDevice device, VkPhysicalDeviceMemoryPro
     return result;
   }
 
-  result = create_graphics_pipeline(device, extent, render_pass, pipeline_info, max_frames_in_flight, out);
+  result = create_graphics_pipeline(device, extent, render_pass, offscreen_render_pass, pipeline_info, max_frames_in_flight, out);
   if(result != VK_SUCCESS) {
     return result;
   }
@@ -2297,6 +2375,12 @@ VulkanContext* init_vulkan(GLFWwindow* window, uint32_t max_frames_in_flight) {
     context->swapchain_command_buffers = swapchain_command_buffers;
   }
 
+  context->offscreen_command_buffers = create_command_buffers(context->device, context->graphics_command_pool, context->max_frames_in_flight);
+  if(swapchain_command_buffers == VK_NULL_HANDLE) {
+    fprintf(stderr, "failed to create vulkan swapchain command buffer\n");
+    return 0;
+  }
+
   VkSemaphore* ia_semaphores = create_semaphores(context->device, 0, max_frames_in_flight);
   if(ia_semaphores == 0) {
     fprintf(stderr, "failed to create vulkan image available semaphores\n");
@@ -2313,6 +2397,11 @@ VulkanContext* init_vulkan(GLFWwindow* window, uint32_t max_frames_in_flight) {
     context->render_finished_semaphores = rf_semaphores;
   }
 
+  context->offscreen_complete_semaphores = create_semaphores(context->device, 0, 1);
+  if(context->offscreen_complete_semaphores == NULL) {
+    return 0;
+  }
+
   VkFence* if_fences = create_fences(context->device, VK_FENCE_CREATE_SIGNALED_BIT, max_frames_in_flight);
   if(if_fences == 0) {
     fprintf(stderr, "failed to create vulkan in flight fence\n");
@@ -2328,7 +2417,7 @@ VulkanContext* init_vulkan(GLFWwindow* window, uint32_t max_frames_in_flight) {
 
   VkImageCreateInfo g_pos_info = {
     .sType = VK_STRUCTURE_TYPE_IMAGE_CREATE_INFO,
-    .usage = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT,
+    .usage = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT,
     .imageType = VK_IMAGE_TYPE_2D,
     .extent = {
       .width = context->swapchain_extent.width,
@@ -2368,6 +2457,168 @@ VulkanContext* init_vulkan(GLFWwindow* window, uint32_t max_frames_in_flight) {
     return 0;
   }
 
+  VkExtent3D offscreen_extent = {
+    .width = context->swapchain_extent.width,
+    .height = context->swapchain_extent.height,
+    .depth = 1,
+  };
+
+  VkImageCreateInfo offscreen_depth_info = {
+    .sType = VK_STRUCTURE_TYPE_IMAGE_CREATE_INFO,
+    .imageType = VK_IMAGE_TYPE_2D,
+    .pNext = NULL,
+    .extent = offscreen_extent,
+    .mipLevels = 1,
+    .arrayLayers = 1,
+    .format = context->depth_format,
+    .tiling = VK_IMAGE_TILING_OPTIMAL,
+    .initialLayout = VK_IMAGE_LAYOUT_UNDEFINED,
+    .usage = VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT,
+    .sharingMode = VK_SHARING_MODE_EXCLUSIVE,
+    .samples = VK_SAMPLE_COUNT_1_BIT,
+    .flags = 0,
+  };
+
+  result = gpu_image_malloc(context->device, context->g_buffer_page, &offscreen_depth_info, &context->g_image_depth);
+  if(result != VK_SUCCESS) {
+    fprintf(stderr, "failed to allocate g_image_depth\n");
+    return 0;
+  }
+
+  VkImageViewCreateInfo g_depth_view_info = {
+    .sType = VK_STRUCTURE_TYPE_IMAGE_VIEW_CREATE_INFO,
+    .image = context->g_image_depth.handle,
+    .viewType = VK_IMAGE_VIEW_TYPE_2D,
+    .format = context->depth_format,
+    .components = {
+      .r = VK_COMPONENT_SWIZZLE_IDENTITY,
+      .g = VK_COMPONENT_SWIZZLE_IDENTITY,
+      .b = VK_COMPONENT_SWIZZLE_IDENTITY,
+      .a = VK_COMPONENT_SWIZZLE_IDENTITY,
+    },
+    .subresourceRange = {
+      .aspectMask = VK_IMAGE_ASPECT_DEPTH_BIT,
+      .baseMipLevel = 0,
+      .levelCount = 1,
+      .baseArrayLayer = 0,
+      .layerCount = 1,
+    },
+  };
+
+  result = vkCreateImageView(context->device, &g_depth_view_info, 0, &context->g_image_view_depth);
+  if(result != VK_SUCCESS) {
+    fprintf(stderr, "Failed to allocate g_image_view_depth\n");
+    return 0;
+  }
+
+  result = command_transition_image_layout(context->device, context->extra_graphics_pool, context->queues.graphics, VK_IMAGE_LAYOUT_UNDEFINED, VK_IMAGE_LAYOUT_DEPTH_ATTACHMENT_OPTIMAL, context->g_image_depth.handle, 0, VK_ACCESS_DEPTH_STENCIL_ATTACHMENT_READ_BIT | VK_ACCESS_DEPTH_STENCIL_ATTACHMENT_WRITE_BIT, VK_PIPELINE_STAGE_TOP_OF_PIPE_BIT, VK_PIPELINE_STAGE_EARLY_FRAGMENT_TESTS_BIT, VK_QUEUE_FAMILY_IGNORED, VK_QUEUE_FAMILY_IGNORED, VK_IMAGE_ASPECT_DEPTH_BIT);
+  if(result != VK_SUCCESS) {
+    fprintf(stderr, "Failed to transition g_image_depth to VK_IMAGE_LAYOUT_DEPTH_ATTACHMENT_OPTIMAL\n");
+    return 0;
+  }
+
+  VkAttachmentDescription offscreen_attachments[] = {
+    {
+      .format = VK_FORMAT_R16G16B16A16_SFLOAT,
+      .samples = VK_SAMPLE_COUNT_1_BIT,
+      .loadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE,
+      .storeOp = VK_ATTACHMENT_STORE_OP_STORE,
+      .stencilLoadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE,
+      .stencilStoreOp = VK_ATTACHMENT_STORE_OP_DONT_CARE,
+      .initialLayout = VK_IMAGE_LAYOUT_UNDEFINED,
+      .finalLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL,
+    },
+    {
+      .format = context->depth_format,
+      .samples = VK_SAMPLE_COUNT_1_BIT,
+      .loadOp = VK_ATTACHMENT_LOAD_OP_CLEAR,
+      .storeOp = VK_ATTACHMENT_STORE_OP_STORE,
+      .stencilLoadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE,
+      .stencilStoreOp = VK_ATTACHMENT_STORE_OP_STORE,
+      .initialLayout = VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL,
+      .finalLayout = VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL,
+    },
+  };
+
+  VkAttachmentReference offscreen_attachment_refs[] = {
+    {
+      .attachment = 0,
+      .layout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL,
+    }
+  };
+
+  VkAttachmentReference offscreen_depth_reference = {
+    .attachment = 1,
+    .layout = VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL,
+  };
+
+  VkSubpassDescription offscreen_pass_descs[] = {
+    {
+      .pipelineBindPoint = VK_PIPELINE_BIND_POINT_GRAPHICS,
+      .colorAttachmentCount = sizeof(offscreen_attachment_refs)/sizeof(VkAttachmentReference),
+      .pColorAttachments = offscreen_attachment_refs,
+      .pDepthStencilAttachment = &offscreen_depth_reference,
+    },
+  };
+
+  VkSubpassDependency offscreen_pass_dependencies[] = {
+    {
+      .srcSubpass = VK_SUBPASS_EXTERNAL,
+      .dstSubpass = 0,
+      .srcStageMask = VK_PIPELINE_STAGE_BOTTOM_OF_PIPE_BIT,
+      .dstStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT | VK_PIPELINE_STAGE_EARLY_FRAGMENT_TESTS_BIT,
+      .srcAccessMask = VK_ACCESS_MEMORY_READ_BIT,
+      .dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_READ_BIT | VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT | VK_ACCESS_DEPTH_STENCIL_ATTACHMENT_WRITE_BIT,
+      .dependencyFlags = VK_DEPENDENCY_BY_REGION_BIT,
+    },
+    {
+      .srcSubpass = 0,
+      .dstSubpass = VK_SUBPASS_EXTERNAL,
+      .srcStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT | VK_PIPELINE_STAGE_EARLY_FRAGMENT_TESTS_BIT,
+      .dstStageMask = VK_PIPELINE_STAGE_BOTTOM_OF_PIPE_BIT,
+      .srcAccessMask = VK_ACCESS_COLOR_ATTACHMENT_READ_BIT | VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT | VK_ACCESS_DEPTH_STENCIL_ATTACHMENT_WRITE_BIT,
+      .dstAccessMask = VK_ACCESS_MEMORY_READ_BIT,
+      .dependencyFlags = VK_DEPENDENCY_BY_REGION_BIT,
+    },
+  };
+
+  VkRenderPassCreateInfo offscreen_pass_info = {
+    .sType = VK_STRUCTURE_TYPE_RENDER_PASS_CREATE_INFO,
+    .attachmentCount = sizeof(offscreen_attachments)/sizeof(VkAttachmentDescription),
+    .pAttachments = offscreen_attachments,
+    .subpassCount = sizeof(offscreen_pass_descs)/sizeof(VkSubpassDescription),
+    .pSubpasses = offscreen_pass_descs,
+    .dependencyCount = sizeof(offscreen_pass_dependencies)/sizeof(VkSubpassDependency),
+    .pDependencies = offscreen_pass_dependencies,
+  };
+
+  result = vkCreateRenderPass(context->device, &offscreen_pass_info, 0, &context->g_renderpass);
+  if(result != VK_SUCCESS) {
+    fprintf(stderr, "Failed to create offscreen renderpass\n");
+    return 0;
+  }
+
+  VkImageView offscreen_fb_attachments[2] = {
+    context->g_image_view_position,
+    context->g_image_view_depth,
+  };
+
+  VkFramebufferCreateInfo offscreen_framebuffer_info = {
+      .sType = VK_STRUCTURE_TYPE_FRAMEBUFFER_CREATE_INFO,
+      .renderPass = context->g_renderpass,
+      .attachmentCount = sizeof(offscreen_fb_attachments)/sizeof(VkImageView),
+      .pAttachments = offscreen_fb_attachments,
+      .width = context->swapchain_extent.width,
+      .height = context->swapchain_extent.height,
+      .layers = 1,
+  };
+
+  result = vkCreateFramebuffer(context->device, &offscreen_framebuffer_info, 0, &context->g_framebuffer);
+  if(result != VK_SUCCESS) {
+    fprintf(stderr, "failed to allocate offscreen framebuffer\n");
+    return 0;
+  }
+
   return context;
 }
 
@@ -2740,7 +2991,7 @@ struct ScenePC get_scene_constants(vec3 world_position, versor world_rotation, f
   return constants;
 }
 
-VkResult draw_frame(VulkanContext* context, SceneContext* scene, uint32_t materials_count, GraphicsPipeline* pipelines, uint32_t* objects_counts, Object** objects, VkDeviceAddress object_buffer_addr) {
+VkResult draw_frame(VulkanContext* context, SceneContext* scene, uint32_t pipelines_count, GraphicsPipeline* pipelines, uint32_t* objects_counts, Object** objects, VkDeviceAddress object_buffer_addr) {
   struct ScenePC scene_constants = get_scene_constants(world_position, world_rotation, (float)context->swapchain_extent.width/(float)context->swapchain_extent.height, 0.01);
 
   VkResult result;
@@ -2765,23 +3016,49 @@ VkResult draw_frame(VulkanContext* context, SceneContext* scene, uint32_t materi
     return result;
   }
 
-  result = command_draw_scene(materials_count, pipelines, objects_counts, objects, context->current_frame, scene->descriptors, &scene_constants, context->swapchain_command_buffers[context->current_frame], context->render_pass, context->swapchain_framebuffers[image_index], context->swapchain_extent, object_buffer_addr);
+  result = command_draw_scene(pipelines_count, pipelines, objects_counts, objects, context->current_frame, scene->descriptors, &scene_constants, context->swapchain_command_buffers[context->current_frame], context->render_pass, context->swapchain_framebuffers[image_index], context->swapchain_extent, object_buffer_addr, 0);
+  if(result != VK_SUCCESS) {
+    return result;
+  }
+
+  result = vkResetCommandBuffer(context->offscreen_command_buffers[context->current_frame], 0);
+  if(result != VK_SUCCESS) {
+    return result;
+  }
+
+  result = command_draw_scene(pipelines_count, pipelines, objects_counts, objects, context->current_frame, scene->descriptors, &scene_constants, context->offscreen_command_buffers[context->current_frame], context->g_renderpass, context->g_framebuffer, context->swapchain_extent, object_buffer_addr, 1);
   if(result != VK_SUCCESS) {
     return result;
   }
 
   VkPipelineStageFlags wait_stages[] = {VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT};
-  VkSubmitInfo submit_info = {
+  VkSubmitInfo offscreen_submit_info = {
     .sType = VK_STRUCTURE_TYPE_SUBMIT_INFO,
     .waitSemaphoreCount = 1,
     .pWaitSemaphores = &context->image_available_semaphores[context->current_frame],
     .pWaitDstStageMask = wait_stages,
     .commandBufferCount = 1,
+    .pCommandBuffers = &context->offscreen_command_buffers[context->current_frame],
+    .signalSemaphoreCount = 1,
+    .pSignalSemaphores = &context->offscreen_complete_semaphores[0],
+  };
+
+  VkSubmitInfo submit_info = {
+    .sType = VK_STRUCTURE_TYPE_SUBMIT_INFO,
+    .waitSemaphoreCount = 1,
+    .pWaitSemaphores = &context->offscreen_complete_semaphores[0],
+    .pWaitDstStageMask = wait_stages,
+    .commandBufferCount = 1,
     .pCommandBuffers = &context->swapchain_command_buffers[context->current_frame],
     .signalSemaphoreCount = 1,
     .pSignalSemaphores = &context->render_finished_semaphores[context->current_frame],
   };
 
+  result = vkQueueSubmit(context->queues.graphics, 1, &offscreen_submit_info, 0);
+  if(result != VK_SUCCESS) {
+    return result;
+  }
+
   result = vkQueueSubmit(context->queues.graphics, 1, &submit_info, context->in_flight_fences[context->current_frame]);
   if(result != VK_SUCCESS) {
     return result;
@@ -2918,7 +3195,7 @@ void main_loop(PlyMesh ply_mesh, GLFWwindow* window, VulkanContext* context) {
 
   GraphicsPipeline simple_mesh_pipeline = {0};
   GraphicsPipeline texture_mesh_pipeline = {0};
-  VkResult result = create_simple_mesh_pipeline(context->device, context->swapchain_extent, context->render_pass, scene.descriptor_layout, context->max_frames_in_flight, &simple_mesh_pipeline);
+  VkResult result = create_simple_mesh_pipeline(context->device, context->swapchain_extent, context->render_pass, context->g_renderpass, scene.descriptor_layout, context->max_frames_in_flight, &simple_mesh_pipeline);
   if(result != VK_SUCCESS) {
     fprintf(stderr, "failed to create simple mesh material: %s\n", string_VkResult(result));
     return;
@@ -2930,7 +3207,7 @@ void main_loop(PlyMesh ply_mesh, GLFWwindow* window, VulkanContext* context) {
     return;
   }
 
-  result = create_texture_mesh_pipeline(context->device, context->memories, context->swapchain_extent, context->render_pass, scene.descriptor_layout, context->max_frames_in_flight, context->transfer_command_pool, context->queues.transfer, context->queues.graphics, context->extra_graphics_pool, context->queue_indices.transfer_family, context->queue_indices.graphics_index, &texture_mesh_pipeline);
+  result = create_texture_mesh_pipeline(context->device, context->memories, context->swapchain_extent, context->render_pass, context->g_renderpass, scene.descriptor_layout, context->max_frames_in_flight, context->transfer_command_pool, context->queues.transfer, context->queues.graphics, context->extra_graphics_pool, context->queue_indices.transfer_family, context->queue_indices.graphics_index, &texture_mesh_pipeline);
   if(result != VK_SUCCESS) {
     fprintf(stderr, "failed to create texture mesh material\n");
     return;