From 0c391fdbce5a079cf03e483eb6174dd47806163d Mon Sep 17 00:00:00 2001
From: chai <chaifix@163.com>
Date: Wed, 7 Aug 2019 21:08:47 +0800
Subject: *misc

---
 Source/modules/asura-core/Image/StbDecoder.cpp | 73 ++++++++++++++++++++++++++
 1 file changed, 73 insertions(+)
 create mode 100644 Source/modules/asura-core/Image/StbDecoder.cpp

(limited to 'Source/modules/asura-core/Image/StbDecoder.cpp')

diff --git a/Source/modules/asura-core/Image/StbDecoder.cpp b/Source/modules/asura-core/Image/StbDecoder.cpp
new file mode 100644
index 0000000..101b148
--- /dev/null
+++ b/Source/modules/asura-core/Image/StbDecoder.cpp
@@ -0,0 +1,73 @@
+#include <asura-base/Exception.h>
+
+#include "StbDecoder.h"
+
+#define STB_IMAGE_IMPLEMENTATION
+#include <stb/stb_image.h>
+
+using namespace AEGraphics;
+
+namespace_begin(AsuraEngine)
+namespace_begin(Image)
+
+bool STBDecoder::CanDecode(FileSystem::DataBuffer& buffer)
+{
+	int w = 0;
+	int h = 0;
+	int comp = 0;
+
+	int status = stbi_info_from_memory((const stbi_uc*)buffer.GetData(), buffer.GetSize(), &w, &h, &comp);
+
+	return status == 1 && w > 0 && h > 0;
+}
+
+void STBDecoder::Decode(FileSystem::DataBuffer& db, ImageData& imageData)
+{
+	const stbi_uc *buffer = (const stbi_uc *)db.GetData();
+	// databuffer数据长
+	int bufferlen = db.GetSize();
+
+	int width, height;
+	int comp = 0;
+	byte* data = nullptr;
+	ColorFormat format = COLOR_FORMAT_UNKNOWN;
+	std::size_t size = 0;
+
+	if (stbi_is_hdr_from_memory(buffer, bufferlen))
+	{
+		// 4个channel都是float
+		data = (byte*)stbi_loadf_from_memory(buffer, bufferlen, &width, &height, &comp, STBI_rgb_alpha);
+		format = COLOR_FORMAT_RGBA32F;
+		size = width * height * 4 * sizeof(float);
+	}
+	else
+	{
+		data = (byte*)stbi_load_from_memory(buffer, bufferlen, &width, &height, &comp, STBI_rgb_alpha);
+		format = COLOR_FORMAT_RGBA8;
+		size = width * height * 4;
+	}
+	if (data)
+	{
+		imageData.Lock();
+
+		if (imageData.pixels)
+			free(imageData.pixels);
+		imageData.pixels = (byte*)data;
+		imageData.format = format;
+		imageData.width  = width;
+		imageData.height = height;
+		imageData.size   = size;
+
+		imageData.Unlock();
+	}
+	else
+	{
+		const char *err = stbi_failure_reason();
+		if (err == nullptr)
+			err = "unknown error";
+		throw Exception("Could not decode image with stb_image (%s).", err);
+	}
+}
+
+namespace_end
+namespace_end
\ No newline at end of file
-- 
cgit v1.1-26-g67d0