Adobe Illustrator can import raster images, and Adobe Photoshop can treat bitmapped layers as objects, but no program comes close to Canvas’s ability to combine vector and bitmapped graphics. In Canvas, a bitmapped image is simply another object, alongside text or vector shapes. If you import a layered Photoshop file, each layer comes into Canvas as a separate paint object. This object-oriented approach provides the framework for the most exciting new feature in Canvas 6, SpriteLayers. This technology lets you layer vector, bitmapped, and text objects with full control over transparency, masking, and transfer modes. No other program provides this level of transparency control. Canvas provides several different ways to apply transparency. The simplest is to select an object and adjust its opacity using a slider. If you’re working with a vector object, you can change the fill opacity while preserving the stroke. You can also apply directional, radial, rectangular, or elliptical transparency fades to any object. You can define objects as vector masks and attach them to other objects, with the masking object’s colour values determining the level of transparency in the underlying object. Build a gradient or paint object with varying degrees of grey, then attach it to another object, and you’ve got a complicated transparency map that doesn’t need extra channels or clipping paths. The program’s most impressive transparency feature is the Channel Mask, which lets you apply opacity variations using any of the program’s brushes. You simply paint the areas you want to make transparent. What’s most amazing is that the feature works with bitmapped and vector objects. For example, you can place a photo of a house over a vector drawing of the interior, and then paint transparency onto the photo layer to create a combination photo and illustration cutaway. Because transparency is implemented as a mask on top of an object, you can edit objects without affecting their masks. You can also apply transparency to groups of objects. However, if you want to edit the individual objects, you must ungroup them, which causes Canvas to remove the transparency channel for that group. Barfly
Canvas 6 sports some interface improvements, although new users should still expect a bit of a learning curve. You can now customize the program’s tool bar, adding buttons or keyboard shortcuts for any feature. The program lacks scripting facilities, but the customization in version 6 helps streamline repetitive tasks. Beneath the tool bar is a new Docking Bar that provides one-click access to any of the program’s numerous palettes. Drag a palette to the Docking Bar, and its name appears there as a simple tab. This great feature compensates for the program’s palette glut. However, rather than listing its palettes in a single menu, Canvas spreads them throughout the menu system, making them difficult to find. Canvas 6 also offers context-sensitive menus – accessible by control-clicking on an item – and a cool new ink-extraction feature: drag any object to the Ink palette, and the program automatically adds its stroke and fill colours to the swatch. Like its predecessor, the upgrade employs a different interface depending on what type of document – page layout, illustration, or presentation – you want to produce. For example, if you create a page layout, you get an interface that provides columns, multiple pages, and master pages; opening a new presentation document brings up a slide-making interface. However, all of these interfaces use the same basic tool set. Unfortunately, some interface troubles remain from the previous version. For example, to modify a vector shape, you must double-click on it to invoke the vector-editing mode, which can only display a wireframe of the object. Canvas 6’s object-oriented approach also makes it difficult to perform document-wide adjustments. For example, you can’t modify shadow, highlight, or midtone levels on an entire document – or even simultaneously on multiple bitmapped objects. If you need to lighten or saturate an entire image, you have to do it one object at a time. We’d like to see something akin to Photoshop’s Adjustment Layers, which make it easy to experiment with different document-wide Levels and Curves adjustments. Canvas 6 implements a new virtual-memory scheme that greatly improves painting performance. Brushes and other painting tools are much peppier and smoother than in previous versions. In version 5, editing a large bitmapped image was unreasonably slow, but the upgrade is adept at handling even large, high-resolution CMYK images. Version 6 also adds new tools for creating three-point ellipses and arcs, along with a Knife tool for slicing objects. Several new features will appeal to technical illustrators: the CAD-like Fillet and Trim commands for making corners; the ability to enter mathematical equations in measurement fields; and a Transform palette that lets you scale, rotate, or skew an object using numeric values. Like its competitors, Canvas 6 provides a full set of layer controls, including a new Guides layer for creating snap-to guides in front of or behind other layers. However, the layer implementation could use some work. To move an object between layers, you must use a Send To Layers menu command. We’d prefer a control in the Layers palette. Deneba has spruced up other Canvas components as well. The Page Layout facility now supports multiple master pages and less flashy options such as Auto Correct spelling checks. However, despite the program’s impressive layout features, most publishing pros will want to stick with a dedicated program, such as QuarkXPress, to ensure support from local service bureaus. Canvas 6 also features a built-in version of Colada, Deneba’s Web publishing facility. Through Colada, you can easily create Java-based rollover buttons and animations. However, we found the resulting HTML somewhat flaky, with buttons occasionally appearing in the wrong places. Most Web designers are better off sticking with a dedicated HTML authoring package. We found other minor instabilities, including the Brush palette’s tendency to show up empty and occasional incompatibilities with certain PostScript Type 1 fonts. However, we experienced no crashes, and Canvas 6’s performance improvements impressed us.
If you’re a current Canvas user, you should buy this upgrade. The new transparency features and bitmap performance improvements alone are worth the price. Illustrator, Photoshop, and Macromedia FreeHand still serve high-end graphics pros better, but Canvas 6’s strong integration of text, painting, and drawing tools makes it a good one-stop graphics application.