LibWeb/WebGL: Don't attempt to do texture transforms on an empty texture

Skia will not give us a surface if the width or height is zero.

Author: Lubrsi

Libraries/LibWeb/WebGL/WebGLRenderingContextBase.cpp

@@ -165,25 +165,29 @@ Optional<WebGLRenderingContextBase::ConvertedTexture> WebGLRenderingContextBase:
 
     auto buffer = MUST(ByteBuffer::create_zeroed(buffer_pitch.value() * height));
 
-    auto skia_format = opengl_format_and_type_to_skia_color_type(format, type);
-
-    // FIXME: Respect UNPACK_PREMULTIPLY_ALPHA_WEBGL
-    // FIXME: Respect unpackColorSpace
-    auto color_space = SkColorSpace::MakeSRGB();
-    auto image_info = SkImageInfo::Make(width, height, skia_format, SkAlphaType::kPremul_SkAlphaType, color_space);
-    auto surface = SkSurfaces::WrapPixels(image_info, buffer.data(), buffer_pitch.value());
-    auto surface_canvas = surface->getCanvas();
-    auto dst_rect = Gfx::to_skia_rect(Gfx::Rect { 0, 0, width, height });
-
-    // The first pixel transferred from the source to the WebGL implementation corresponds to the upper left corner of
-    // the source. This behavior is modified by the UNPACK_FLIP_Y_WEBGL pixel storage parameter, except for ImageBitmap
-    // arguments, as described in the abovementioned section.
-    if (m_unpack_flip_y && !source.has<GC::Root<HTML::ImageBitmap>>()) {
-        surface_canvas->translate(0, dst_rect.height());
-        surface_canvas->scale(1, -1);
-    }
+    if (width > 0 && height > 0) {
+        // FIXME: Respect UNPACK_PREMULTIPLY_ALPHA_WEBGL
+        // FIXME: Respect unpackColorSpace
+        auto skia_format = opengl_format_and_type_to_skia_color_type(format, type);
+        auto color_space = SkColorSpace::MakeSRGB();
+        auto image_info = SkImageInfo::Make(width, height, skia_format, SkAlphaType::kPremul_SkAlphaType, color_space);
+        auto surface = SkSurfaces::WrapPixels(image_info, buffer.data(), buffer_pitch.value());
+        VERIFY(surface);
+        auto surface_canvas = surface->getCanvas();
+        auto dst_rect = Gfx::to_skia_rect(Gfx::Rect { 0, 0, width, height });
+
+        // The first pixel transferred from the source to the WebGL implementation corresponds to the upper left corner of
+        // the source. This behavior is modified by the UNPACK_FLIP_Y_WEBGL pixel storage parameter, except for ImageBitmap
+        // arguments, as described in the abovementioned section.
+        if (m_unpack_flip_y && !source.has<GC::Root<HTML::ImageBitmap>>()) {
+            surface_canvas->translate(0, dst_rect.height());
+            surface_canvas->scale(1, -1);
+        }
 
-    surface_canvas->drawImageRect(bitmap->sk_image(), dst_rect, Gfx::to_skia_sampling_options(Gfx::ScalingMode::NearestNeighbor));
+        surface_canvas->drawImageRect(bitmap->sk_image(), dst_rect, Gfx::to_skia_sampling_options(Gfx::ScalingMode::NearestNeighbor));
+    } else {
+        VERIFY(buffer.is_empty());
+    }
 
     return ConvertedTexture {
         .buffer = move(buffer),