Bug 1209812 (part 1) - Remove casts between cairo_format_t and gfxImageFormat. r=nical.

cairo_format_t and gfxImageFormat have their equivalent constants in the same
order, so you can just cast between them, which is kind of nasty.

This patch replaces all such casts with explicit conversions via calls to new
conversion functions. These functions will be removed in a subsequent patch.

gfx/thebes/gfxASurface.cpp

@@ -424,7 +424,8 @@ gfxASurface::CheckSurfaceSize(const IntSize& sz, int32_t limit)
 int32_t
 gfxASurface::FormatStrideForWidth(gfxImageFormat format, int32_t width)
 {
-    return cairo_format_stride_for_width((cairo_format_t)(int)format, (int)width);
+    cairo_format_t cformat = gfxImageFormatToCairoFormat(format);
+    return cairo_format_stride_for_width(cformat, (int)width);
 }
 
 nsresult

gfx/thebes/gfxBaseSharedMemorySurface.h

@@ -77,8 +77,8 @@ public:
         mozilla::gfx::IntSize size(shmInfo->width, shmInfo->height);
         if (!gfxASurface::CheckSurfaceSize(size))
             return nullptr;
-       
+
-        gfxImageFormat format = (gfxImageFormat)shmInfo->format;
+        gfxImageFormat format = shmInfo->format;
         long stride = gfxImageSurface::ComputeStride(size, format);
 
         RefPtr<Sub> s =

gfx/thebes/gfxImageSurface.cpp

@@ -32,7 +32,7 @@ gfxImageSurface::InitFromSurface(cairo_surface_t *csurf)
     mSize.width = cairo_image_surface_get_width(csurf);
     mSize.height = cairo_image_surface_get_height(csurf);
     mData = cairo_image_surface_get_data(csurf);
-    mFormat = (gfxImageFormat) cairo_image_surface_get_format(csurf);
+    mFormat = gfxCairoFormatToImageFormat(cairo_image_surface_get_format(csurf));
     mOwnsData = false;
     mStride = cairo_image_surface_get_stride(csurf);
 
@@ -66,9 +66,10 @@ gfxImageSurface::InitWithData(unsigned char *aData, const IntSize& aSize,
     if (!CheckSurfaceSize(aSize))
         MakeInvalid();
 
+    cairo_format_t cformat = gfxImageFormatToCairoFormat(mFormat);
     cairo_surface_t *surface =
         cairo_image_surface_create_for_data((unsigned char*)mData,
-                                            (cairo_format_t)(int)mFormat,
+                                            cformat,
                                             mSize.width,
                                             mSize.height,
                                             mStride);
@@ -135,9 +136,10 @@ gfxImageSurface::AllocateAndInit(long aStride, int32_t aMinimalAllocation,
 
     mOwnsData = true;
 
+    cairo_format_t cformat = gfxImageFormatToCairoFormat(mFormat);
     cairo_surface_t *surface =
         cairo_image_surface_create_for_data((unsigned char*)mData,
-                                            (cairo_format_t)(int)mFormat,
+                                            cformat,
                                             mSize.width,
                                             mSize.height,
                                             mStride);
@@ -162,7 +164,7 @@ gfxImageSurface::gfxImageSurface(cairo_surface_t *csurf)
     mSize.width = cairo_image_surface_get_width(csurf);
     mSize.height = cairo_image_surface_get_height(csurf);
     mData = cairo_image_surface_get_data(csurf);
-    mFormat = (gfxImageFormat) cairo_image_surface_get_format(csurf);
+    mFormat = gfxCairoFormatToImageFormat(cairo_image_surface_get_format(csurf));
     mOwnsData = false;
     mStride = cairo_image_surface_get_stride(csurf);
 

gfx/thebes/gfxQPainterSurface.cpp

@@ -21,9 +21,9 @@ gfxQPainterSurface::gfxQPainterSurface(QPainter *painter)
 
 gfxQPainterSurface::gfxQPainterSurface(const mozilla::gfx::IntSize& size, gfxImageFormat format)
 {
-    cairo_surface_t *csurf = cairo_qt_surface_create_with_qimage ((cairo_format_t) format,
+    cairo_format_t cformat = gfxImageFormatToCairoFormat(format);
-                                                                        size.width,
+    cairo_surface_t *csurf =
-                                                                        size.height);
+        cairo_qt_surface_create_with_qimage(cformat, size.width, size.height);
     mPainter = cairo_qt_surface_get_qpainter (csurf);
 
     Init (csurf);

gfx/thebes/gfxQuartzSurface.cpp

@@ -26,8 +26,8 @@ gfxQuartzSurface::gfxQuartzSurface(const gfxSize& desiredSize, gfxImageFormat fo
     unsigned int width = static_cast<unsigned int>(mSize.width);
     unsigned int height = static_cast<unsigned int>(mSize.height);
 
-    cairo_surface_t *surf = cairo_quartz_surface_create
+    cairo_format_t cformat = gfxImageFormatToCairoFormat(format);
-        ((cairo_format_t) format, width, height);
+    cairo_surface_t *surf = cairo_quartz_surface_create(cformat, width, height);
 
     mCGContext = cairo_quartz_surface_get_cg_context (surf);
 
@@ -109,8 +109,9 @@ gfxQuartzSurface::gfxQuartzSurface(unsigned char *data,
     unsigned int width = static_cast<unsigned int>(mSize.width);
     unsigned int height = static_cast<unsigned int>(mSize.height);
 
+    cairo_format_t cformat = gfxImageFormatToCairoFormat(format);
     cairo_surface_t *surf = cairo_quartz_surface_create_for_data
-        (data, (cairo_format_t) format, width, height, stride);
+        (data, cformat, width, height, stride);
 
     mCGContext = cairo_quartz_surface_get_cg_context (surf);
 
@@ -131,8 +132,9 @@ gfxQuartzSurface::gfxQuartzSurface(unsigned char *data,
     if (!CheckSurfaceSize(aSize))
         MakeInvalid();
 
+    cairo_format_t cformat = gfxImageFormatToCairoFormat(format);
     cairo_surface_t *surf = cairo_quartz_surface_create_for_data
-        (data, (cairo_format_t) format, aSize.width, aSize.height, stride);
+        (data, cformat, aSize.width, aSize.height, stride);
 
     mCGContext = cairo_quartz_surface_get_cg_context (surf);
 

gfx/thebes/gfxTypes.h

@@ -57,6 +57,18 @@ enum class gfxImageFormat {
   Unknown
 };
 
+// XXX: temporary
+// This works because the gfxImageFormat enum is defined so as to match the
+// _cairo_format enum.
+#define gfxCairoFormatToImageFormat(aFormat) \
+    ((gfxImageFormat)aFormat)
+
+// XXX: temporary
+// This works because the gfxImageFormat enum is defined so as to match the
+// _cairo_format enum.
+#define gfxImageFormatToCairoFormat(aFormat) \
+    ((cairo_format_t)aFormat)
+
 enum class gfxSurfaceType {
   Image,
   PDF,

gfx/thebes/gfxWindowsSurface.cpp

@@ -59,8 +59,9 @@ gfxWindowsSurface::gfxWindowsSurface(const mozilla::gfx::IntSize& realSize, gfxI
     if (!CheckSurfaceSize(size))
         MakeInvalid(size);
 
-    cairo_surface_t *surf = cairo_win32_surface_create_with_dib((cairo_format_t)(int)imageFormat,
+    cairo_format_t cformat = gfxImageFormatToCairoFormat(imageFormat);
-                                                                size.width, size.height);
+    cairo_surface_t *surf =
+        cairo_win32_surface_create_with_dib(cformat, size.width, size.height);
 
     Init(surf);
 
@@ -79,8 +80,10 @@ gfxWindowsSurface::gfxWindowsSurface(HDC dc, const mozilla::gfx::IntSize& realSi
     if (!CheckSurfaceSize(size))
         MakeInvalid(size);
 
-    cairo_surface_t *surf = cairo_win32_surface_create_with_ddb(dc, (cairo_format_t)(int)imageFormat,
+    cairo_format_t cformat = gfxImageFormatToCairoFormat(imageFormat);
-                                                                size.width, size.height);
+    cairo_surface_t *surf =
+        cairo_win32_surface_create_with_ddb(dc, cformat,
+                                            size.width, size.height);
 
     Init(surf);
 
@@ -138,9 +141,11 @@ gfxWindowsSurface::CreateSimilarSurface(gfxContentType aContent,
         // a surface that's the result of create_similar(gfxContentType::COLOR_ALPHA)
         // (e.g. a backbuffer for the window) --- that new surface *would*
         // have a DIB.
-        surface =
+        gfxImageFormat gformat =
-          cairo_win32_surface_create_with_dib((cairo_format_t)(int)gfxPlatform::GetPlatform()->OptimalFormatForContent(aContent),
+            gfxPlatform::GetPlatform()->OptimalFormatForContent(aContent);
-                                              aSize.width, aSize.height);
+        cairo_format_t cformat = gfxImageFormatToCairoFormat(gformat);
+        surface = cairo_win32_surface_create_with_dib(cformat, aSize.width,
+                                                      aSize.height);
     } else {
         surface =
           cairo_surface_create_similar(mSurface, (cairo_content_t)(int)aContent,

gfx/thebes/gfxXlibNativeRenderer.cpp

@@ -352,7 +352,7 @@ CreateTempXlibSurface (cairo_surface_t* cairoTarget,
         } else if (cairoTargetType == CAIRO_SURFACE_TYPE_IMAGE || drawTarget) {
             gfxImageFormat imageFormat =
                 drawTarget ? SurfaceFormatToImageFormat(drawTarget->GetFormat()) :
-                    (gfxImageFormat)cairo_image_surface_get_format(cairoTarget);
+                    gfxCairoFormatToImageFormat(cairo_image_surface_get_format(cairoTarget));
             target_visual = gfxXlibSurface::FindVisual(screen, imageFormat);
             Display *dpy = DisplayOfScreen(screen);
             if (target_visual) {