You can always start by drawing a few basic curves and lines. I suggest starting with the wheel height, upper to establish a mid-point for the car, and lower to establish a bottom as well as a mid-point for the wheels/axles where the chassis/frame will be concerned later on (be they regular or monster wheels), determine how you want the wheels oriented in the image, and draw accordingly, starting with lines to line them up, and then circles/ovals to orient them FOIL (First Outer, Inner Last) style (to also line up the diameters if both wheels are at different visual angles (front facing camera, rear/car is facing left/right; don't forget to also include a slight gap between frame and wheel, and if you're crazy-detailed, work on a hub design, and design the brake system behind it as well). Where the hubcaps are concerned as well, determine the diameter of the wheels/tires and the hubs, so you have a consistent form/style), I advise to keep the initial lines for reference or aerodynamic lines/creases later on; depending on the style of car you're designing. Don't forget to assign a center point to make the wheels look convincing, including the tread details.
Next, establish the chassis you want, with the wheels as a frame of reference as to the scale. Doors are usually between 1.5-2x wheel height/diameter. Don't forget to also determine the car's ride height as well (how high from the ground the car's frame settles from the ground, relative to the wheels' axles/center (midnight racers nearly touching the floor, monster trucks way up high (way above the centers to the point of being completely over the wheels themselves), etc., you know; that kind of stuff.). A good starting point for style would also be working on the hood or the lights first, and then working backwards towards the windshields (front or back, depending on which way the car's facing).
Then just keep improving the detail of the image after you established a rough, kinda like how an image does a progressive loading, or how games improve detail using LOD rendering (think Borderlands as you watch things improve in quality over a short time, especially if you move quickly). Clean up the edges and correction points, and there you go, a snazzy new car exactly how you want it.
To help come up with a good angle, especially to achieve desired results a little quicker/easily, draw a couple circles or rectangles (wheel angles), and line up an I or X/double-wishbone frame and a mock outline chassis to find a desired angle you want to render the car before committing to an overall design, as well as to determine how many doors you want and etc.. It's similar to figure drawing and using stick figures to initially determine the pose you want the character to have when you render them. This pre-drawing phase can also help you come up with a good design and wheel drawing practice when you want to determine the diameters for later rendering when it comes time to work on them. Wheels on cars are like eyes on a figure/face. You can easily screw them up, and it can affect the overall image big time.
EDIT:
Oh yeah, when it comes to harder angles of rendering, where less of the car is visible (showing off the front or back), don't forget about foreshortening the visible sides, and how the rear-view mirrors stick out like ears on a face. It also doesn't hurt to work on a basic interior design as well, at least as background shadows. Wheel width can also affect the image as badly as the mirrors and hub design. It also helps to keep the wheel widths in mind as well to line up the ground with the rest of the car so it doesn't look like the car is on uneven ground (and look like it had a flat tire somewhere).
I've drawn cars and ships/machines and such before. I hope my advice helps. My preferred method of development: engineer it before you design it (how it works, how well it works, it's main purpose, how it will bind/hold together, etc.). Let the practicality of the design design it for you, and design the additional touches to make it stand out more (practicality before prettiness). Sometimes the 'ugly' duckling will turn into an overall badass design without needing to turn into a swan at all.
Snazzy, huh? The front engines can adjust their vector in order to add more speed to the turn of the ship, and the rear "thorax" of the ship is bearing-stabilized to add some curve to the frame in order to adapt to various air-currents, depending on how sharply the ship has to turn. The rear engine block has a couple vector-thrust engine blocks in it as well in order to further add, or adjust to a sharp turn.
With a united effort of the engines and the other parts of the ship (elevators, ailerons, spoilers, flaps, and rudders), it is actually possible for this thing to do a drift in the sky like a rally car. Not to mention, with all the other parts working together, this thing, despite it's scale, can also do some barnstorming, fly upside-down and etc.. I have crazy pilots in mind for flying this bastard, and designed it accordingly.
As time passes since the original design, I even MacGuyvered the under-wing hangar system to serve as a makeshift missile launcher; even adapting the under-belly catapult system to operate similarly. Meaning this thing can fire both laser/plasma weapons as well as kinetic weapons (auto-cannons in the frame, rockets/torpedoes out the hangars/aerial ship catapult)). This thing is made to bring in the hurt.
Alternatively, look into the Bloodfist design as well. I had to adjust the modeling/concept work to fit DF's profile, and to make it as visually appealing as well as a functional structure in-game. Turned out rather impressive, for what it's worth.
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Topic: Have to draw a "dream car" for school. Advice? (Read 3584 times)