added Bitmap I/O in TGAFormat

inc/hgl/2d/BitmapLoad.h

@@ -0,0 +1,90 @@
+#pragma once
+#include<hgl/2d/Bitmap.h>
+#include<hgl/io/FileInputStream.h>
+
+namespace hgl
+{
+    namespace bitmap
+    {
+        struct BitmapLoader
+        {
+            virtual const uint OnChannels()const=0;
+            virtual const uint OnChannelBits()const=0;
+
+            const uint OnPixelBits()const
+            {
+                return OnChannelBits()*OnChannels();
+            }
+
+            virtual void *OnRecvBitmap(uint w,uint h)=0;
+
+            virtual void OnLoadFailed()=0;
+            virtual void OnFlip()=0;
+        };
+
+        template<typename T> struct BitmapLoaderImpl:public BitmapLoader
+        {
+            T *bmp;
+
+        public:
+
+            BitmapLoaderImpl()
+            {
+                bmp=nullptr;
+            }
+    
+            const uint OnChannels()const override{return bmp->GetChannels();}
+            const uint OnChannelBits()const override{return bmp->GetChannelBits();}
+
+            void *OnRecvBitmap(uint w,uint h) override
+            {
+                if(!bmp)
+                    bmp=new T;
+
+                bmp->Create(w,h);
+                return bmp->GetData();
+            }
+
+            void OnLoadFailed() override
+            {
+                SAFE_CLEAR(bmp);
+            }
+
+            void OnFlip() override
+            {
+                if(bmp)
+                    bmp->Flip();
+            }
+        };
+
+        bool LoadBitmapFromTGAStream(io::InputStream *,BitmapLoader *);
+
+        template<typename T>
+        inline T *LoadBitmapFromTGA(io::InputStream *is)
+        {
+            BitmapLoaderImpl<T> bli;
+
+            if(LoadBitmapFromTGAStream(is,&bli))
+                return bli.bmp;
+
+            return(nullptr);
+        }
+
+        inline BitmapRGB8 *LoadBitmapRGB8FromTGA(io::InputStream *is){return LoadBitmapFromTGA<BitmapRGB8>(is);}
+        inline BitmapRGBA8 *LoadBitmapRGBA8FromTGA(io::InputStream *is){return LoadBitmapFromTGA<BitmapRGBA8>(is);}
+
+        template<typename T>
+        inline T *LoadBitmapFromTGA(const OSString &filename)
+        {
+            io::OpenFileInputStream fis(filename);
+
+            if(!fis)
+                return(false);
+
+            return LoadBitmapFromTGA<T>(&fis);
+        }
+
+        inline BitmapRGB8 *LoadBitmapRGB8FromTGA(const OSString &filename){return LoadBitmapFromTGA<BitmapRGB8>(filename);}
+        inline BitmapRGBA8 *LoadBitmapRGBA8FromTGA(const OSString &filename){return LoadBitmapFromTGA<BitmapRGBA8>(filename);}
+    }//namespace bitmap
+}//namespace hgl