init

Chapter01/05_BC7Compression/CMakeLists.txt

@@ -0,0 +1,7 @@
+cmake_minimum_required(VERSION 3.19)
+project(Chapter01)
+include(../../CMake/CommonMacros.txt)
+SETUP_APP(Ch01_05_BC7Compression "Chapter 01")
+
+target_include_directories(Ch01_05_BC7Compression PUBLIC ${CMAKE_SOURCE_DIR})
+target_link_libraries(Ch01_05_BC7Compression SharedUtils)

Chapter01/05_BC7Compression/src/main.cpp

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+#include <stdint.h>
+#include <stdio.h>
+
+#include <ktx-software/lib/gl_format.h>
+#include <ktx-software/lib/vkformat_enum.h>
+#include <ktx.h>
+
+#include <stb/stb_image.h>
+#include <stb/stb_image_resize2.h>
+
+#include <lvk/LVK.h>
+
+int main(int argc, char *argv[]) {
+  const int numChannels = 4;
+  int origW, origH;
+  const uint8_t *pixels =
+      stbi_load("data/wood.jpg", &origW, &origH, nullptr, numChannels);
+
+  assert(pixels);
+
+  const uint32_t numMipLevels = lvk::calcNumMipLevels(origW, origH);
+
+  ktxTextureCreateInfo createInfoKTX2 = {
+      .glInternalformat = GL_RGBA8,
+      .vkFormat = VK_FORMAT_BC7_UNORM_BLOCK,
+      .baseWidth = (uint32_t)origW,
+      .baseHeight = (uint32_t)origH,
+      .baseDepth = 1u,
+      .numDimensions = 2u,
+      .numLevels = numMipLevels,
+      .numLayers = 1u,
+      .numFaces = 1u,
+      .generateMipmaps = KTX_FALSE,
+  };
+  ktxTexture2 *textureKTX2 = nullptr;
+  (void)LVK_VERIFY(ktxTexture2_Create(&createInfoKTX2,
+                                      KTX_TEXTURE_CREATE_ALLOC_STORAGE,
+                                      &textureKTX2) == KTX_SUCCESS);
+
+  int w = origW;
+  int h = origH;
+
+  for (uint32_t i = 0; i != numMipLevels; ++i) {
+    size_t offset = 0;
+    ktxTexture_GetImageOffset(ktxTexture(textureKTX2), i, 0, 0, &offset);
+
+    stbir_resize_uint8_linear((const unsigned char *)pixels, origW, origH, 0,
+                              ktxTexture_GetData(ktxTexture(textureKTX2)) +
+                                  offset,
+                              w, h, 0, STBIR_RGBA);
+
+    h = h > 1 ? h >> 1 : 1;
+    w = w > 1 ? w >> 1 : 1;
+  }
+
+  (void)LVK_VERIFY(ktxTexture2_CompressBasis(textureKTX2, 255) == KTX_SUCCESS);
+  (void)LVK_VERIFY(ktxTexture2_TranscodeBasis(textureKTX2, KTX_TTF_BC7_RGBA,
+                                              0) == KTX_SUCCESS);
+
+  // convert to KTX1
+  ktxTextureCreateInfo createInfoKTX1 = {
+      .glInternalformat = GL_COMPRESSED_RGBA_BPTC_UNORM,
+      .vkFormat = VK_FORMAT_BC7_UNORM_BLOCK,
+      .baseWidth = (uint32_t)origW,
+      .baseHeight = (uint32_t)origH,
+      .baseDepth = 1u,
+      .numDimensions = 2u,
+      .numLevels = numMipLevels,
+      .numLayers = 1u,
+      .numFaces = 1u,
+      .generateMipmaps = KTX_FALSE,
+  };
+  ktxTexture1 *textureKTX1 = nullptr;
+  (void)LVK_VERIFY(ktxTexture1_Create(&createInfoKTX1,
+                                      KTX_TEXTURE_CREATE_ALLOC_STORAGE,
+                                      &textureKTX1) == KTX_SUCCESS);
+
+  for (uint32_t i = 0; i != numMipLevels; ++i) {
+    size_t offset1 = 0;
+    (void)LVK_VERIFY(ktxTexture_GetImageOffset(ktxTexture(textureKTX1), i, 0, 0,
+                                               &offset1) == KTX_SUCCESS);
+    size_t offset2 = 0;
+    (void)LVK_VERIFY(ktxTexture_GetImageOffset(ktxTexture(textureKTX2), i, 0, 0,
+                                               &offset2) == KTX_SUCCESS);
+    memcpy(ktxTexture_GetData(ktxTexture(textureKTX1)) + offset1,
+           ktxTexture_GetData(ktxTexture(textureKTX2)) + offset2,
+           ktxTexture_GetImageSize(ktxTexture(textureKTX1), i));
+  }
+
+  ktxTexture_WriteToNamedFile(ktxTexture(textureKTX1), ".cache/image.ktx");
+  ktxTexture_Destroy(ktxTexture(textureKTX1));
+  ktxTexture_Destroy(ktxTexture(textureKTX2));
+
+  return 0;
+}