Fast and smooth graphics within a little game...

Hi to all of you who read this thread!

I want to get suggestions about the following:

I want to make a little game (for example: 2D Football) with Fast and Smooth graphics!!
The main tool I can use is Direct X 7.

Any suggestions?

Thank you in advance,
Arie.

u can also use bitblt...its fast!

Not fast enough for 1024x768 fullscreen games thought.

That's true. The big reason for that is that directx can draw directly to the front buffer rather than copying from a backbuffer.

Not exactly... DX uses hardware acceleration wherever possible. You can't even BitBlt a single 1024x768 front buffers with reasonable performance. However for small games or such where you don't have to draw a full screen in each frame BitBlt is just fine. Though you don't get rotations and all the other nice features when using DXGraphics.

I want to make a full screen 800x600 game. I see that DX is the best choise this far...

Any other suggestions?

Arie.

OpenGL? But I would rather go with DX if I was you...

Ok... Direct X was chosen.
Now, When I mess with the game loops, I usually use GetTickCount within a While loop. Should I use another looping tool?

Thank you,
Arie.

Yes. Use a while loop, but instead of waiting for a specified time to elapse before updating your world state, instead, calculate the elapsed time between frames and update at each loop:

Code:

---

Dim l As Long
Dim t As Long
Dim delta As Single
...
While running
  l = t
  t = GetTickCount()
  delta = (t - l) / 1000
  'Update
  'Draw
  DoEvents
Wend

---

You would then use delta in all update caluclations. For instance, an object is supposed to move 10 meters per second. You give that object a normalized (magnitude == 1) direction vector, and a velocity of 10. To calculate the new position of that object at each update you would do this:

Code:

---

nx = dir.x * vel * delta
ny = dir.y * vel * delta

---

This gives you correct, frame rate independant movement.

Z.

"Ah yes," thank you Fox. Hardware acceleration is the big reason. I left the screwdriver in my ear.

Ok, sounds good...
Now, I have a Direct Draw Q:

When I draw (BltFast) a surface that his width or height is out limited from the screen, it is not drawn. Why?

Thank you,
Arie.

I am not sure why it is doing that. But you have to calculate the width and hight and the X Y coordinates so it can fit on the screen. I can't remember if it is BlTFast or just Blt that has the oppurtunity to have all those values as parameters, but just try with BltFast first.

Got it. As a continue for the game building:
When I want to get as many keys as possible at the same time.
I usually use GetAsyncKeyState, but when I press many keys (3+) it doesn't get them... Maybe it's my comp.

What is the way to get keys from the user?
What should I use in a two or more players game?

Thank you,
Arie.

DX can handel your keyboard inputs too. But if you don't want to use it, you could always use the Key down and up events.

Set a boolean variable (array?) to true for every key that is pushed in the key down event. Then in the game look, check what keys that is pushed and do what ever it is supposed to do. Then in the key up event set the boolean variables to false. And so on....;)

Quote:

---

Originally posted by Arie
Got it. As a continue for the game building:
When I want to get as many keys as possible at the same time.
I usually use GetAsyncKeyState, but when I press many keys (3+) it doesn't get them... Maybe it's my comp.

What is the way to get keys from the user?
What should I use in a two or more players game?

Thank you,
Arie.

---

The problem with many keys is actually a problem with the wiring in your keyboard... everyone's does that.

Z.

try this:

VB Code:

Private Declare Function GetKeyboardState Lib "user32" (pbKeyState As Byte) As Long
Dim bKeys(255) As Byte
 
Call GetKeyboardState(bKeys(0))
If ((bKeys(vbKeyUp) And 128) = 128) And ((bKeys(vbKeyLeft) And 128) = 128) Then
    'both keys are pressed
End If

Quote:

---

Originally posted by Zaei
The problem with many keys is actually a problem with the wiring in your keyboard... everyone's does that.

Z.

---

With my method I am pretty sure that you could at leas press 6 keys at the same time....

I managed to make it work with 8 keys on my machine with the messiest code I could think of at this minute....look here....

Quote:

---

Originally posted by NoteMe
I managed to make it work with 8 keys on my machine with the messiest code I could think of at this minute....look here....

---

Right. There is an upper limit on all keyboards. It's a hardware problem.

Z.

Whats wrong with DX Input??? :confused: :confused: :confused:

Quote:

---

Originally posted by NoteMe
I managed to make it work with 8 keys on my machine with the messiest code I could think of at this minute....look here....

---

This is a good one NoteMe. Thank you.

Now I want to ask:
How do I test my Direct Play (Multiplayer) without using another comp?

Thank you,
Arie.

You should be able to start a server and a client on the same machine.

Z.

where can i get a direct x programming tutorial???

Try out dirextx4vb.com everything you nee there....and BTW look in the DX SDK too....some things you will find intresting there too....

How do I make a part of a surface rotate?

Thank you,
Arie.

Rotateing at runtime will sow your game down, you need to either load up a series of frames all of different rotation or rotate it before starting the game and rotate it into memory.

Are you using DX or a picture box???

Use DXGraphics and simply rotate the edge points of the destination polygons that form your surface. See the Mouse Attack thread and download it's code; the DXGraphics module (especially the Blt function) might be of interest.

I am using Direct X, Direct Draw. How do I rotate a surface?

Thank you,
Arie.

See attached

This is actually from my own app so a few changes are needed

ByRef Pic1 As DirectDrawSurface7 = Returned Surface


ByVal I As Integer = Angle (0 to 15) (16 Angles in my game)

The RotateOffset Variable contains degrees per value of I this was for a quick change. To have it as 360 just change it to 1.

UnitName As String = Folder name from app.path

Position As String = Filename of picture


I hope that makes sense :D :D :D :D

See what attached? Where?

Arie.

How strange

Is this procedure fast?

any other code?

Thank you,
Arie.

I didn't look at the other code, but here is an other example.....

This is an excellent example of Rotating a Surface!!!

Thank you very much, NoteMe.

Arie.

No problem. But remember that it is not as fast as if you make 60 pictures of the car at design time, and makes a sprite of all of them, and just changes the picture of the car if it moves....

Tried it on my game. Two notes:

1) It is way too slow...

2) I can't rotate a part of a surface.

So you say that I have no other choise... I must draw 360 pictures?

Thank you,
Arie.

No that is not what I am saying. First of all, why do you need 360 pictures. You can't need one for every degree. That sounds like to many for a game. An other thing you could do is make a game that rotates and saves a picture in as many angles as you want. And if you are lucky I a have sutch a app....

Here it is....


BTW why do you need to rotate parts of a surface. Show me an example of a surface that you need to rotate parts of it...

i improved the rotate function that NoteMe attached...its alot faster now!

The first one I posted? Or the one that saves pictures that is rotated?

I saw it now....I used it when I started out my GTA clone....never finished that one. But it was a nice tool to have when I wanted many cars.......:D So it actually was fast enough on my fast machine.....;)

ok...hehe...
heres a version that creates masks too :)

i think you could use this code to rotate in realtime :) ...if you use something faster than setpixel...

But it will still be faster to mak the pictures at design time....or use the DX version I posted...

Let me say clearly what I want:

I have one picture (32x32) with a white background.
I want to be able to draw the picture at any angle (0-359) with a
transparent background (using color key, white), as FAST as possible.

That's pretty much it,
Arie.

As mentioned... use DXGraphics.

Ok. I mean using DX Graphics, but I'll need some rotating code.

Arie.

No one has a fast rotating code using DDraw?

Arie.

Quote:

---

Originally posted by Arie
No one has a fast rotating code using DDraw?

Arie.

---

I am so confused. Was my code not fast enough, or did you just not see it?

The GTA Clone code, works fine within itself.
But when I used the same code in my game, It was too slow.

Any other way to rotate, better than GetLockedPixel?

Arie.

Waiting...

Other suggestions (code) are welcome.

Arie.

Isn't it a little too much code(mod_VSA_surf.bas), and complicated?

Does anyone has another way, simpler one, similar to the GTA Clone?

Thank you,
Arie.

I see that you have a car picture with all angles, you should have just draw according to the angle.
It's not what I'm looking for.

I want a single picture, that 'll be able to rotate in any angle.

Thank you,
Arie.

You can't have everything in the world. Use the code that you got. Choose the fastest one. If it is not fast enough in your code, maybe it is something "wrong" with it, and you can try to build it faster. If that is impossible, try to figgure an other way around, like drawing all the pics in front and use them. You can't notice the diffrence between a car made up of 60 pics or just some rotating code. That is at least my oppinion on that case....

Ok, ok.. relax. :rolleyes:

I just thought that if I'm using Direct Draw, It can easily rotate a surface. but I see that it can't. so I'll go on the traditional way, draw all the angles I need.

Yet, any other suggestions are welcome!
Arie.

Ok, ok.. relax. :rolleyes:

I just thought that if I'm using Direct Draw, It can easily rotate a surface. but I see that it can't. so I'll go on the traditional way, draw all the angles I need.

Yet, any other suggestions are welcome!
Arie.

Now, I want to make my ball game a smooth game with a great collision... Does anyone have a full commented tutorial for this?

Thank you,
Arie.

I updated my engine. AlphaBlit is faster, a bunch of things are fixed (like if vbBlue was maskcolor, it would actually choose red), better things for you to try in Form_Load, updated comments about the sprite loader in the .doc file.

I would really love to know what you did there in that great project.
But, I need a simpler example of collision...

I know I need to check the distance between the two balls,
and if its smaller the 2R then I need to apply a crash between them.
Set an angle and speed, how do I set them?

Thank you,
Arie.

speed should be a no-brainer.

for angle, you'll have to find which image array element of sprite (calling it Ball in this example) corresponds with your angle.

0.0 for angle is straight up. pi / 2 is 90 degrees pointing right

Elem = GetSurfaceElementFromAngle(Ball, angle)
RGBBlit MyBackBuf, Ball.Surface(Elem), x, y