Add ktx

ktx/examples/vkload.cpp

@@ -0,0 +1,150 @@
+// Copyright 2018-2020 The Khronos Group Inc.
+// SPDX-License-Identifier: Apache-2.0
+
+#include <vulkan/vulkan.h>
+#include <ktxvulkan.h>
+// Use c++ to keep the example short. Not required.
+#include <vulkan/vulkan.hpp>
+
+class Texture {
+  public:
+    Texture(const std::string ktxfile);
+    ~Texture();
+
+  protected:
+    ktxVulkanTexture texture;
+    vk::PhysicalDevice gpu;
+    vk::Device device;
+    vk::Queue queue;
+    vk::CommandPool commandPool;
+
+    cleanup();
+    prepareSamplerAndView();
+};
+
+Texture::Texture(const std::string ktxfile)
+{
+    ktxVulkanDeviceInfo kvdi;
+    ktxTexture* kTexture;
+    KTX_error_code ktxresult;
+
+    createVulkanInstance();
+    findVulkanGpu();         // Find a suitable physical device
+    createVulkanSurface();
+    createVulkanDevice();
+    prepareVulkanSwapchain();
+    /*
+          .
+          .
+          .
+    */
+
+    // This structure is used to pass the Vulkan device information to the loader
+    // with the expectation that app's will typically load many textures.
+    ktxVulkanDeviceInfo_Construct(&kvdi, gpu, device, queue, commandPool, nullptr);
+
+    ktxresult = ktxTexture_CreateFromNamedFile(
+                                        (getAssetPath() + ktxfile).c_str(),
+                                        KTX_TEXTURE_CREATE_NO_FLAGS,
+                                        &kTexture);
+    if (KTX_SUCCESS != ktxresult) {
+        std::stringstream message;
+
+        message << "Creation of ktxTexture from \"" << getAssetPath()
+                << ktxfile << "\" failed: " << ktxErrorString(ktxresult);
+        throw std::runtime_error(message.str());
+    }
+    ktxresult = ktxTexture_VkUploadEx(kTexture, &kvdi, &texture,
+                                      VK_IMAGE_TILING_OPTIMAL,
+                                      VK_IMAGE_USAGE_SAMPLED_BIT,
+                                      VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL);
+    if (KTX_SUCCESS != ktxresult) {
+        std::stringstream message;
+
+        message << "ktxTexture_VkUpload failed: " << ktxErrorString(ktxresult);
+        throw std::runtime_error(message.str());
+    }
+
+    char* pValue;
+    uint32_t valueLen;
+    if (KTX_SUCCESS == ktxHashTable_FindValue(&kTexture->kvDataHead,
+                                              KTX_ORIENTATION_KEY,
+                                              &valueLen, (void**)&pValue))
+    {
+        char s, t;
+
+        if (sscanf(pValue, KTX_ORIENTATION2_FMT, &s, &t) == 2) {
+            if (s == 'l') sign_s = -1;
+            if (t == 'u') sign_t = -1;
+        }
+    }
+
+    ktxTexture_Destroy(kTexture);
+    ktxVulkanDeviceInfo_destruct(&kvdi);
+
+    try {
+        prepareSamplerAndView(); // See below  for implementation.
+        // Setup a layout with, e.g., a binding for a combined image-sampler.
+        setupDescriptorSetLayout();
+        // Create a descriptor set and update it with the sampler and image view handles.
+        setupDescriptorSet();
+        preparePipelines();
+        setupDescriptorPool();
+        setupDescriptorSet();
+        buildCommandBuffers();
+    } catch (std::exception&) {
+        cleanup();
+        throw;
+    }
+}
+
+Texture::~Texture()
+{
+    cleanup();
+}
+
+Texture::cleanup()
+{
+    destroyCommandBuffers();
+    destroySampler();
+    destroyImageview();
+    ktxVulkanTexture_destruct(&texture, device, nullptr);
+    /*
+          .
+          .
+          .
+    */
+}
+
+void
+Texture::prepareSamplerAndView()
+{
+    // Create sampler.
+    vk::SamplerCreateInfo samplerInfo;
+    // Set the non-default values
+    samplerInfo.magFilter = vk::Filter::eLinear;
+    samplerInfo.minFilter = vk::Filter::eLinear;
+    samplerInfo.mipmapMode = vk::SamplerMipmapMode::eLinear;
+    samplerInfo.maxLod = texture.levelCount;
+    samplerInfo.anisotropyEnable = false;
+    samplerInfo.maxAnisotropy = 1.0;
+    samplerInfo.borderColor = vk::BorderColor::eFloatOpaqueWhite;
+    sampler = vkctx.device.createSampler(samplerInfo);
+
+    // Create image view.
+    // Textures are not directly accessed by the shaders and are abstracted
+    // by image views containing additional information and sub resource
+    // ranges.
+    vk::ImageViewCreateInfo viewInfo;
+    // Set the non-default values.
+    viewInfo.image = texture.image;
+    viewInfo.format = static_cast<vk::Format>(texture.imageFormat);
+    viewInfo.viewType = static_cast<vk::ImageViewType>(texture.viewType);
+    viewInfo.subresourceRange.aspectMask = vk::ImageAspectFlagBits::eColor;
+    viewInfo.subresourceRange.layerCount = texture.layerCount;
+    viewInfo.subresourceRange.levelCount = texture.levelCount;
+    imageView = vkctx.device.createImageView(viewInfo);
+}
+
+/* -*- tab-width: 4; -*- */
+/* vi: set sw=2 ts=4 expandtab: */