Added GDI+ images support

demo/gdip/nuklear_gdip.h

@@ -1,7 +1,7 @@
 /*
- * Nuklear - v1.17 - public domain
+ * Nuklear - v1.20 - public domain
  * no warrenty implied; use at your own risk.
- * authored from 2015-2016 by Micha Mettke
+ * authored from 2015-2017 by Micha Mettke
  */
 /*
  * ==============================================================
@@ -27,6 +27,10 @@ NK_API int nk_gdip_handle_event(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lpara
 NK_API void nk_gdip_render(enum nk_anti_aliasing AA, struct nk_color clear);
 NK_API void nk_gdip_shutdown(void);
 
+/* image */
+NK_API struct nk_image nk_gdip_load_image_from_file(const WCHAR* filename);
+NK_API struct nk_image nk_gdip_load_image_from_memory(const void* membuf, int membufSize);
+
 #endif
 /*
  * ==============================================================
@@ -191,6 +195,18 @@ GdipDisposeImage(GpImage *image);
 GpStatus WINGDIPAPI
 GdipGetImageGraphicsContext(GpImage *image, GpGraphics **graphics);
 
+GpStatus WINGDIPAPI
+GdipGetImageWidth(GpImage *image, UINT *width);
+
+GpStatus WINGDIPAPI
+GdipGetImageHeight(GpImage *image, UINT *height);
+
+GpStatus WINGDIPAPI
+GdipLoadImageFromFile(GDIPCONST WCHAR* filename, GpImage **image);
+
+GpStatus WINGDIPAPI
+GdipLoadImageFromStream(IStream* stream, GpImage **image);
+
 /* pen */
 
 GpStatus WINGDIPAPI
@@ -283,7 +299,7 @@ GdipFillPieI(GpGraphics *graphics, GpBrush *brush, INT x, INT y,
 
 GpStatus WINGDIPAPI
 GdipDrawRectangleI(GpGraphics *graphics, GpPen *pen, INT x, INT y,
-                      INT width, INT height);
+                   INT width, INT height);
 
 GpStatus WINGDIPAPI
 GdipFillRectangleI(GpGraphics *graphics, GpBrush *brush, INT x, INT y,
@@ -326,6 +342,10 @@ GdipGraphicsClear(GpGraphics *graphics, ARGB color);
 GpStatus WINGDIPAPI
 GdipDrawImageI(GpGraphics *graphics, GpImage *image, INT x, INT y);
 
+GpStatus WINGDIPAPI 
+GdipDrawImageRectI(GpGraphics *graphics, GpImage *image, INT x, INT y, 
+                   INT width, INT height);
+
 GpStatus WINGDIPAPI
 GdipMeasureString(
     GpGraphics               *graphics,
@@ -538,6 +558,14 @@ nk_gdip_draw_text(short x, short y, unsigned short w, unsigned short h,
     GdipDrawString(gdip.memory, wstr, wsize, font->handle, &layout, gdip.format, gdip.brush);
 }
 
+static void
+nk_gdip_draw_image(short x, short y, unsigned short w, unsigned short h,
+    struct nk_image img, struct nk_color col)
+{
+    GpImage *image = img.handle.ptr;
+    GdipDrawImageRectI(gdip.memory, image, x, y, w, h);
+}
+
 static void
 nk_gdip_clear(struct nk_color col)
 {
@@ -550,6 +578,43 @@ nk_gdip_blit(GpGraphics *graphics)
     GdipDrawImageI(graphics, gdip.bitmap, 0, 0);
 }
 
+struct nk_image
+nk_gdip_image_to_nk(GpImage *image){
+    struct nk_image img;
+    UINT uwidth, uheight;
+    img = nk_image_ptr( (void*)image );
+    GdipGetImageHeight(image, &uheight);
+    GdipGetImageWidth(image, &uwidth);
+    img.h = uheight;
+    img.w = uwidth;
+    return img;
+}
+
+struct nk_image
+nk_gdip_load_image_from_file(GDIPCONST WCHAR *filename)
+{
+    GpImage *image;
+    GdipLoadImageFromFile(filename, &image);
+    return nk_gdip_image_to_nk(image);
+}
+
+struct nk_image
+nk_gdip_load_image_from_memory(const void *membuf, int membufSize)
+{
+    GpImage *image = NULL;
+    IStream *pStream = NULL;
+    HGLOBAL hMem = GlobalAlloc(GMEM_MOVEABLE, membufSize);
+    LPVOID pImage = GlobalLock(hMem);
+    nk_memcopy(pImage, membuf, membufSize);
+    GlobalUnlock(hMem);
+    
+    /* CreateStreamOnHGlobal needs OLE32 in linked libraries list */
+    CreateStreamOnHGlobal(hMem, FALSE, &pStream);
+    GdipLoadImageFromStream(pStream, &image);
+    GlobalFree(hMem);
+    return nk_gdip_image_to_nk(image);
+}
+
 GdipFont*
 nk_gdipfont_create(const char *name, int size)
 {
@@ -991,8 +1056,11 @@ nk_gdip_render(enum nk_anti_aliasing AA, struct nk_color clear)
             nk_gdip_stroke_curve(q->begin, q->ctrl[0], q->ctrl[1],
                 q->end, q->line_thickness, q->color);
         } break;
+        case NK_COMMAND_IMAGE: {
+            const struct nk_command_image *i = (const struct nk_command_image *)cmd;
+            nk_gdip_draw_image(i->x, i->y, i->w, i->h, i->img, i->col);
+        } break;
         case NK_COMMAND_RECT_MULTI_COLOR:
-        case NK_COMMAND_IMAGE:
         case NK_COMMAND_ARC:
         case NK_COMMAND_ARC_FILLED:
         default: break;
@@ -1003,4 +1071,3 @@ nk_gdip_render(enum nk_anti_aliasing AA, struct nk_color clear)
 }
 
 #endif
-