diff --git a/src/api/graphics.c b/src/api/graphics.c
index da048f30..7c8ec053 100644
--- a/src/api/graphics.c
+++ b/src/api/graphics.c
@@ -786,7 +786,7 @@ int l_lovrGraphicsNewMaterial(lua_State* L) {
     lovrMaterialSetTexture(material, TEXTURE_DIFFUSE, texture);
     lovrRelease(&texture->ref);
   } else if (lua_isuserdata(L, index)) {
-    Texture* texture = luax_checktype(L, index++, Texture);
+    Texture* texture = luax_checktypeof(L, index++, Texture);
     lovrMaterialSetTexture(material, TEXTURE_DIFFUSE, texture);
   }
 
diff --git a/src/graphics/canvas.c b/src/graphics/canvas.c
index 3751fe72..c0b5ddf9 100644
--- a/src/graphics/canvas.c
+++ b/src/graphics/canvas.c
@@ -111,14 +111,14 @@ void lovrCanvasBind(Canvas* canvas) {
     lovrGraphicsSetProjection(projection);
   } else {
     mat4 projection = lovrGraphicsGetProjection();
-    float b = -projection[5];
+    float b = projection[5];
     float c = projection[10];
     float d = projection[14];
     float aspect = (float) width / height;
     float k = (c - 1.f) / (c + 1.f);
     float near = (d * (1.f - k)) / (2.f * k);
     float far = k * near;
-    float fov = -2.f * atan(1.f / b);
+    float fov = 2.f * atan(1.f / b);
     float newProjection[16];
     mat4_perspective(newProjection, near, far, fov, aspect);
     lovrGraphicsSetProjection(newProjection);
diff --git a/src/graphics/graphics.c b/src/graphics/graphics.c
index 099974fd..25a23512 100644
--- a/src/graphics/graphics.c
+++ b/src/graphics/graphics.c
@@ -605,10 +605,10 @@ void lovrGraphicsPlane(DrawMode mode, Material* material, mat4 transform) {
     lovrGraphicsDrawPrimitive(material, GL_LINE_LOOP, false, false, false);
   } else if (mode == DRAW_MODE_FILL) {
     float data[] = {
-      -.5, .5, 0,  0, 0, -1, 0, 0,
-      -.5, -.5, 0, 0, 0, -1, 0, 1,
-      .5, .5, 0,   0, 0, -1, 1, 0,
-      .5, -.5, 0,  0, 0, -1, 1, 1
+      -.5, .5, 0,  0, 0, -1, 0, 1,
+      -.5, -.5, 0, 0, 0, -1, 0, 0,
+      .5, .5, 0,   0, 0, -1, 1, 1,
+      .5, -.5, 0,  0, 0, -1, 1, 0
     };
 
     lovrGraphicsSetDefaultShader(SHADER_DEFAULT);
diff --git a/src/loaders/model.c b/src/loaders/model.c
index 5af02bbb..1e20068a 100644
--- a/src/loaders/model.c
+++ b/src/loaders/model.c
@@ -193,7 +193,7 @@ ModelData* lovrModelDataCreate(Blob* blob) {
   struct aiPropertyStore* propertyStore = aiCreatePropertyStore();
   aiSetImportPropertyInteger(propertyStore, AI_CONFIG_PP_SBP_REMOVE, aiPrimitiveType_POINT | aiPrimitiveType_LINE);
   aiSetImportPropertyInteger(propertyStore, AI_CONFIG_PP_SBBC_MAX_BONES, 48);
-  unsigned int flags = aiProcessPreset_TargetRealtime_MaxQuality | aiProcess_OptimizeGraph | aiProcess_FlipUVs | aiProcess_SplitByBoneCount;
+  unsigned int flags = aiProcessPreset_TargetRealtime_MaxQuality | aiProcess_OptimizeGraph | aiProcess_SplitByBoneCount;
   const struct aiScene* scene = aiImportFileExWithProperties(blob->name, flags, &assimpIO, propertyStore);
   aiReleasePropertyStore(propertyStore);
 
diff --git a/src/loaders/texture.c b/src/loaders/texture.c
index d4fd8775..cbb76a31 100644
--- a/src/loaders/texture.c
+++ b/src/loaders/texture.c
@@ -163,7 +163,7 @@ TextureData* lovrTextureDataFromBlob(Blob* blob) {
     return textureData;
   }
 
-  stbi_set_flip_vertically_on_load(0);
+  stbi_set_flip_vertically_on_load(1);
   textureData->format = FORMAT_RGBA;
   textureData->data = stbi_load_from_memory(blob->data, blob->size, &textureData->width, &textureData->height, NULL, 4);
   textureData->blob = NULL;
diff --git a/src/luax.h b/src/luax.h
index 1870c118..19176165 100644
--- a/src/luax.h
+++ b/src/luax.h
@@ -12,10 +12,11 @@
 #define luax_checktypeof(L, i, T) \
   *(T**) (luaL_argcheck(L, lua_touserdata(L, i), i, "Expected " STRINGIFY(T)), \
   lua_getmetatable(L, i), \
-  lua_getfield(L, -1, "super"), \
+  lua_getfield(L, -1, "name"), \
+  lua_getfield(L, -2, "super"), \
   lua_pushstring(L, #T), \
-  luaL_argcheck(L, lua_equal(L, -1, -2), i, "Expected " STRINGIFY(T)), \
-  lua_pop(L, 3), \
+  luaL_argcheck(L, lua_equal(L, -1, -2) || lua_equal(L, -1, -3), i, "Expected " STRINGIFY(T)), \
+  lua_pop(L, 4), \
   lua_touserdata(L, i))
 #define luax_newobject(L, T, x) \
   T** u = (T**) lua_newuserdata(L, sizeof(T**)); \