Initial project import

tools/v/vlib/stbi/stbi_test.v

@@ -0,0 +1,114 @@
+import os
+import stbi
+
+const vroot = @VEXEROOT
+const tfolder = os.join_path(os.vtmp_dir(), 'stbi')
+const logo_path = os.join_path(vroot, 'examples/assets/logo.png')
+const background_path = os.join_path(vroot, 'examples/flappylearning/assets/img/background.png')
+
+fn testsuite_begin() {
+	os.mkdir_all(tfolder) or {}
+}
+
+fn testsuite_end() {
+	os.rmdir_all(tfolder) or {}
+}
+
+fn test_stbi_read_write() {
+	println('Source path: ${logo_path}')
+	d_s := stbi.load(logo_path) or { panic(err) }
+	println('Image source data:\n ${d_s}')
+
+	out_path := os.join_path(tfolder, 'test.png')
+	println('Out path: ${out_path}')
+	stbi.stbi_write_png(out_path, d_s.width, d_s.height, 4, d_s.data, d_s.width * 4) or {
+		panic(err)
+	}
+
+	d_d := stbi.load(out_path) or { panic(err) }
+	println('Image dest data:\n ${d_d}')
+
+	assert d_s.width == d_d.width
+	assert d_s.height == d_d.height
+	assert d_s.nr_channels == d_d.nr_channels
+	assert d_s.original_nr_channels == 4
+
+	mut v_s := unsafe { &u32(d_s.data) }
+	mut v_d := unsafe { &u32(d_d.data) }
+	mut delta := i64(0)
+	for index in 0 .. (d_d.width * d_d.width) {
+		unsafe {
+			delta += v_s[index] - v_d[index]
+		}
+	}
+	assert 0 == delta
+	os.rm(out_path) or {}
+}
+
+fn test_stbi_resize() {
+	println('Source path: ${logo_path}')
+	d_s := stbi.load(logo_path) or { panic(err) }
+	println('Image source data:\n ${d_s}')
+
+	new_width, new_height := 100, 100
+
+	d_r := stbi.resize_uint8(d_s, new_width, new_height) or { panic(err) }
+	assert d_r.original_nr_channels == 4
+	println('Resized Image source data:\n ${d_s}')
+
+	out_path := os.join_path(tfolder, 'test.png')
+	println('Out path: ${out_path}')
+	stbi.stbi_write_png(out_path, d_r.width, d_r.height, 4, d_r.data, d_r.width * 4) or {
+		panic(err)
+	}
+
+	d_d := stbi.load(out_path) or { panic(err) }
+	println('Image dest data:\n ${d_d}')
+
+	assert d_d.width == new_width
+	assert d_d.height == new_height
+	assert d_d.nr_channels == d_r.nr_channels
+	assert d_d.original_nr_channels == 4
+	os.rm(out_path) or {}
+}
+
+fn test_load_image_with_channels_different_than_4() {
+	img := stbi.load(background_path)!
+	assert img.nr_channels == 4, 'by default, stbi.load should convert images to 4 channels'
+	assert img.original_nr_channels == 3, 'the default, should not affect the img.original_nr_channels field; it should be based solely on the original image data on disk'
+
+	img_resized := stbi.resize_uint8(img, 128, 128)!
+	assert img_resized.nr_channels == 4
+	assert img_resized.original_nr_channels == 3
+
+	img3 := stbi.load(background_path, desired_channels: 0)!
+	assert img3.nr_channels == 3, 'stbi.load, with desired_channels: 0, should return an image, without any conversion. the nr_channels should be determined by the image data'
+	assert img.original_nr_channels == 3, 'the default, should not affect the img.original_nr_channels field; it should be based solely on the original image data on disk'
+
+	img3_resized := stbi.resize_uint8(img3, 128, 128)!
+	assert img3_resized.nr_channels == 3
+	assert img3_resized.original_nr_channels == 3
+}
+
+fn test_load_image_from_memory_with_channels_different_than_4() {
+	background_bytes := os.read_bytes(background_path)!
+
+	img := stbi.load_from_memory(background_bytes.data, background_bytes.len)!
+	assert img.nr_channels == 4, 'by default, stbi.load_from_memory should convert images to 4 channels'
+	assert img.original_nr_channels == 3, 'the default should preserve the original channel count as metadata'
+
+	img3 := stbi.load_from_memory(background_bytes.data, background_bytes.len, desired_channels: 0)!
+	assert img3.nr_channels == 3, 'load_from_memory should preserve the source channel count when desired_channels is 0'
+	assert img3.original_nr_channels == 3
+}
+
+fn test_load_from_file_matches_memory_decode() {
+	background_bytes := os.read_bytes(background_path)!
+	img_from_file := stbi.load(background_path)!
+	img_from_memory := stbi.load_from_memory(background_bytes.data, background_bytes.len)!
+	assert img_from_file.width == img_from_memory.width
+	assert img_from_file.height == img_from_memory.height
+	assert img_from_file.nr_channels == img_from_memory.nr_channels
+	assert img_from_file.original_nr_channels == img_from_memory.original_nr_channels
+	assert img_from_file.ext == 'png'
+}