Real easy to do. Just needs a little math. So suppose your grid is based on 16x16 sized squares. So if a block is anywhere from pixel (I'll just be talking about horizontally so the x-axis but the same will apply to the vertical Y-axis) 0-15, it will be in grid 1 and if it is in 16-31, then grid 2 and so on. So lets pick a pixel location say at x position 17. Take that number 17 and divide by the size of your grids which is 16. 17/16 = 1.0625. Now we want to use the floor fuction on that number so the floor(1.0625) = 1. Now multiply your new number 1 by the size of your grid which is...16! And you get 16. So any location from 0-15 will become 0, any location from 16 to 31 will become 16 and so on.

Here's some more math stuff you can play around with.

scirra.com/manual/126/system-expressions

I haven't tried this but I would create a rectangular sprite that is red and that covers the whole screen. I would then set the Opacity to oscillate from 100 (red) to 0 (completely transparent) using the SINE behavior.

It sounds like what the problem is you have the game subtract health "when overlapping the wall?" as opposed to "on collision with the wall?" The game rapidly constinues to subtract health in the blink of an eye cause the player is still "overlapping" the wall. But if it tests for "on collision", it should only take a hit once even if the player is standing by the wall. The player will then have to break contact with the wall and "collide" again to trigger more health loss. Also, you don't need a compare variable to determine if health is equal to zero. Just compare your global "health" variable directly to zero, not to another variable that is equal to zero cause that's redundant.

I'm trying to emulate the side scrolling Mario games as best I can and the difficulty that I'm encountering is how to mimic the jump control. In the real Mario games, the long you hold down the button, the higher he jumps. I see you didn't bother to incorporate that into your game. I wonder if there are examples of someone doing that.

Post a .capx

Sounds like an "invert"? On the event sheet, right click on the event and you have the option to make it "inverted".

Sure thing. Someone else answered a question I had so I felt it was my mission to return the favor to someone else. Besides, I learned some stuff to by making it so it's always good to try a different problem that I wouldn't have considered tackling otherwise. If you have any questions about it, feel free to contact me.

With a price tag of $3,675.00, it's a considerable investment but if you're serious, than more power to you.

I googled "tank sprites" under the Images for Google and it comes up with quite a bit of seperated tank bodies and turrets. Since you are just doing top down, it seems like a realatively simple 2d top down sprite would do? Unless you really want that smooth rotating effect in which case you would either need a few more in between animation frames to make it look smooth or you would still need to go the more elaborate route of making a three dimensional model. Just making some top down 2d sprites would be much easier so probably best to go that route at first. If there is a tank model that you see that has the body partially covered up by the turret, you could still just cut off the turret and recreate the missing body of the tank based on the rest of the tank that you can still see.

Okay so since you know how to use Photoshop CS5, it sounds like your question is really "How do you acquire the skill set to be able to create cool looking sprites?" The best answer I could give is to practice and take art classes and graphical design classes. If you just want to make 2d sprites, than you just do it and that's all there is to it. Somebody had to start from scratch. If you're fine with your art looking similar to someone elses, than do your best to emulate without plagerizing. You could create a three dimensional model of the object if you want to have realistic lighting effects and make it look more 3D. I would use Blender.

You're asking how they did it? Like are you really asking which program they used to make it and what skill sets are required to created graphics like that? Or are you just exclaiming HOW DID THEY DO THAT as in it's really awesome looking and you're impressed with it? If you proclaim that you "suck at graphics designing" and you would still like to give it a shot, I would suggest you just use some basic editing program like MS paint or Paint.NET and you just google around for images that are similar to what you want and you can try to emulate those images so at least you aren't starting from scratch.

But from the number of rep points you have, you don't seem to be a new kid to the world of game design so I'm scratching my head a bit at what you're really asking here?

The main challenge that I am seeing is how you would allow the user to create a sprite shape and then the computer will dynamically know the boundary of that shape. I know you can create any shape you want and change the bounding box to fit that shape. But that customization of the bounding box is done by the designer of the game. I'm not sure if it's possible to give the user the ability to do that on the fly.

But to answer your initial question of how to draw lines with physics behavior, it sounds like you are asking two different questions. If the question was just how do you add physic characteristics to a line, than that's easy as you would just draw a sprite that looks like a line and give it the behavior or physics. But you're probably asking more about the drawing part meaning how does a user dynamically create a sprite with a fitted bounding box and that's of course the hard part.

So to answer your question, I don't know. But I'd be interested if it can be done.