Core (Tests): Add unit test for loading PNGs.

Author: kaixiong

libvisual/tests/images/additive-colors-argb32.png

@@ -6,6 +6,10 @@ LV_BUILD_TEST(video_blit_test
   SOURCES video_blit_test.cpp
 )
 
+LV_BUILD_TEST(video_load_test
+  SOURCES video_load_test.cpp
+)
+
 IF(HAVE_SDL)
   LV_BUILD_TEST(video_scale_test
     SOURCES   video_scale_test.cpp

libvisual/tests/images/additive-colors-argb32.raw

@@ -0,0 +1,146 @@
+#include "test.h"
+#include <libvisual/libvisual.h>
+#include <bit>
+#include <filesystem>
+#include <fstream>
+#include <optional>
+
+namespace
+{
+  LV::VideoPtr load_raw_image (std::filesystem::path const& path, int width, int height, VisVideoDepth depth)
+  {
+      auto image {LV::Video::create (width, height, depth)};
+
+      std::size_t const content_bytes_per_row = image->get_width () * image->get_bpp ();
+
+      {
+          std::ifstream input {path, std::ios::binary};
+          if (!input) {
+              return nullptr;
+          }
+
+          for (int y = 0; y < image->get_height (); y++) {
+              auto pixel_row_ptr = static_cast<char*> (image->get_pixel_ptr (0, y));
+              if (!input.read (pixel_row_ptr, content_bytes_per_row)) {
+                  return nullptr;
+              }
+          }
+      }
+
+      if constexpr (std::endian::native == std::endian::little) {
+          auto byteswapped_image {LV::Video::create (width, height, depth)};
+          byteswapped_image->flip_pixel_bytes (image);
+          return byteswapped_image;
+      } else {
+          return image;
+      }
+  }
+
+  std::optional<LV::Palette> load_raw_palette(std::filesystem::path const& path)
+  {
+      std::vector<std::uint8_t> palette_buffer (256 * 3);
+      {
+          std::ifstream input {path, std::ios::binary};
+          if (!input.read(reinterpret_cast<char*>(palette_buffer.data()), palette_buffer.size())) {
+              return {};
+          }
+      }
+
+      LV::Palette palette;
+      palette.colors.reserve(256);
+      for (unsigned int i = 0; i < 256; i++) {
+          palette.colors.emplace_back(palette_buffer[i*3], palette_buffer[i*3+1], palette_buffer[i*3+2]);
+      }
+
+      return palette;
+  }
+
+  LV::VideoPtr load_raw_indexed_image (std::filesystem::path const& image_path,
+                                       std::filesystem::path const& palette_path,
+                                       int width,
+                                       int height,
+                                       VisVideoDepth depth)
+  {
+      if (depth != VISUAL_VIDEO_DEPTH_24BIT) {
+          return nullptr;
+      }
+
+      auto image {LV::Video::create (width, height, VISUAL_VIDEO_DEPTH_8BIT)};
+
+      std::size_t const content_bytes_per_row = image->get_width () * image->get_bpp ();
+
+      {
+          std::ifstream input {image_path, std::ios::binary};
+          if (!input) {
+              return nullptr;
+          }
+
+          for (int y = 0; y < image->get_height (); y++) {
+              auto pixel_row_ptr = static_cast<char*> (image->get_pixel_ptr (0, y));
+              if (!input.read (pixel_row_ptr, content_bytes_per_row)) {
+                  return nullptr;
+              }
+          }
+      }
+
+      auto palette {load_raw_palette(palette_path)};
+      if (!palette.has_value()) {
+          return nullptr;
+      }
+      image->set_palette (palette.value());
+
+      auto final_image {LV::Video::create (image->get_width(), image->get_height(), VISUAL_VIDEO_DEPTH_24BIT)};
+      final_image->convert_depth(image);
+
+      return final_image;
+  }
+
+  void test_png_load ()
+  {
+      {
+          auto png_image {LV::Video::create_from_file ("../images/additive-colors-indexed8.png")};
+          LV_TEST_ASSERT (png_image);
+
+          auto raw_image {load_raw_indexed_image ("../images/additive-colors-indexed8.raw",
+                                                  "../images/additive-colors-indexed8.raw.pal",
+                                                  png_image->get_width (),
+                                                  png_image->get_height (),
+                                                  VISUAL_VIDEO_DEPTH_24BIT)};
+
+          LV_TEST_ASSERT (png_image->has_same_content (raw_image));
+      }
+
+      {
+          auto png_image {LV::Video::create_from_file ("../images/additive-colors-rgb24.png")};
+          LV_TEST_ASSERT (png_image);
+
+          auto raw_image {load_raw_image ("../images/additive-colors-rgb24.raw",
+                                          png_image->get_width (),
+                                          png_image->get_height (),
+                                          VISUAL_VIDEO_DEPTH_24BIT)};
+
+          LV_TEST_ASSERT (png_image->has_same_content (raw_image));
+      }
+
+      {
+          auto png_image {LV::Video::create_from_file ("../images/additive-colors-argb32.png")};
+          LV_TEST_ASSERT (png_image);
+
+          auto raw_image {load_raw_image ("../images/additive-colors-argb32.raw",
+                                          png_image->get_width (),
+                                          png_image->get_height (),
+                                          VISUAL_VIDEO_DEPTH_32BIT)};
+
+          LV_TEST_ASSERT (png_image->has_same_content (raw_image));
+      }
+  }
+}
+
+int main (int argc, char* argv[])
+{
+    LV::System::init (argc, argv);
+
+    test_png_load ();
+
+    LV::System::destroy ();
+}