Jump to content
Have You Played Atari Today?
2600|5200|7800|Lynx|Jaguar|Forums|Store
IGNORED

Rain?

First Spear

By First Spear
in Intellivision Programming

 Share

Recommended Posts

First Spear River Patroller

First Spear

Posted
Posted (edited)

 

 

Question for Those Smarter Than Me :

 

How could a full-creek rain effect me done, graphically? I am thinking of diagonally-falling rain drops. With the tile and shape limits, I am not sure how it could be done at all.

 

Purely an academic question, I have no practical need for it.

Edited by First Spear
  • Like 1
Link to comment
Share on other sites
catsfolly Dragonstomper

catsfolly

Posted
Posted (edited)

Question for Those Smarter Than Me :

 

How could a full-creek rain effect me done, graphically? I am thinking of diagonally-falling rain drops. With the tile and shape liwmits, I am not sure how it could be done at all.

 

Purely an academic question, I have no practical need for it.

Whilst we wait for those smart people to show up, I'll try some diagonal rain brainstorming...

 

1. The most straightforward way to do rain would be to use the motion objects. Of course this means that you could only have 8 raindrops at a time.

(Unless you multiplex the objects - that would cause them to flicker, which might be okay for raindrops. )

 

The big problem is that you usually need the motion objects for other things - like player characters and enemies and shots and explosions...

 

2. If you have blank background characters, you could assign them to a gram character, and draw new rain animation frames every interrupt to the gram character. If you have a genius graphics designer (or just work on it for a ridiculously long time), you could maybe design the animation so that the raindrops exiting the gram character at the end of the animation match up with raindrops entering the character at the start of the animation - that way the animation will "tile" over several backtab characters.

 

You can set the motion object priority so these backtab drops appear on top of the motion objects.

 

3. If your background is full of custom characters, you can try adding an animation (like in step 2 above) to each gram card. Then the rain will be on top of the graphics (of course it will be the same color as whatever is in the gram card). Since you can only write about 20 gram cards per interrupt, this could only work for simple backgrounds.

 

4. If you loosen the connections between the Intellivision and your tv, you can sometimes get a "snow" effect. It's not rain, though... (nor is it diagonal)...

 

That's all I can think of at the moment...

 

COME ON SMART PEOPLE!

 

 

Catsfolly

Edited by catsfolly
  • Like 1
Link to comment
Share on other sites
catsfolly Dragonstomper

catsfolly

Posted
Posted

Here are some simple experiments, so people have something to criticize:

 

1. A single dot animated (click to animate) :

 

post-14916-0-52316000-1490945274_thumb.gif

 

2. 2 dots in a line (click to animate):

 

post-14916-0-65249500-1490945276_thumb.gif

 

 

3. A separate dot moves at a different speed (click to animate):

 

post-14916-0-37360500-1490945279_thumb.gif

 

 

Here is the source code:

 

r.bas

 

Catsfolly

 

  • Like 4
Link to comment
Share on other sites
mmarrero Star Raider

mmarrero

Posted
Posted

My attempt at rain looks more like 2 extra weeks of winter.

post-35249-0-87295100-1490966669_thumb.gif

I'm also redefining a single card, but using a giant bitmap instead of real animation.

 

 

'--rain2 by Marco A. Marrero
include "constants.bas"
DIM rain,#i,j
GOTO init
'------
'cls/w card, destroys #i,j
DEF FN CLSC(colorcard) = #i=colorcard:GOSUB CLSC_
CLSC_: PROCEDURE 
    FOR j=0 TO BACKGROUND_COLUMNS*BACKGROUND_ROWS -1
        #BACKTAB(j)=#i
    NEXT j
END
'-----
init:
    'clsc(SPR00 + FG_BLUE) '--rain
    clsc(SPR00 + FG_WHITE) '--rain
    FOR j=0 to 3
        '--I'm using GROM cards, I have to multiply by 8 to convert IntyBasic strings to card
        SPRITE j, 54+j*16 + VISIBLE + ZOOMX2, 40 + ZOOMY4,  RainText(j)*8 + SPR_CYAN
        SPRITE j+4, 52+j*16 + VISIBLE + ZOOMX2, 42 + ZOOMY4,  RainText(j)*8 + SPR_BLUE  + BEHIND
    NEXT j

mainloop:
    rain=(rain - 1) AND $7
    DEFINE 0,1,VARPTR RainBitmap(rain)
    FOR j=0 to 6:WAIT:NEXT j
GOTO mainloop

'RainText: DATA "Rain"
RainText: DATA "Snow"

RainBitmap:
BITMAP "        "   '0
BITMAP "        "   '1
BITMAP "        "   '2
BITMAP "      x "   '3
BITMAP "       x"   '4
BITMAP "        "   '5
BITMAP "        "   '6
BITMAP " x      "   '7
BITMAP "  x     "   '8
BITMAP "        "   '9
BITMAP "        "   'A
BITMAP "    x   "   'B
BITMAP "     x  "   'C
BITMAP "        "   'D
BITMAP "        "   'E
BITMAP "        "   'F
BITMAP "        "   '10
BITMAP "        "   '11

 

 

  • Like 4
Link to comment
Share on other sites
Rev Quadrunner

Rev

Posted
Posted

My attempt at rain looks more like 2 extra weeks of winter.

attachicon.gifrain2.gif

I'm also redefining a single card, but using a giant bitmap instead of real animation.

 

 

 

'--rain2 by Marco A. Marrero
include "constants.bas"
DIM rain,#i,j
GOTO init
'------
'cls/w card, destroys #i,j
DEF FN CLSC(colorcard) = #i=colorcard:GOSUB CLSC_
CLSC_: PROCEDURE 
    FOR j=0 TO BACKGROUND_COLUMNS*BACKGROUND_ROWS -1
        #BACKTAB(j)=#i
    NEXT j
END
'-----
init:
    'clsc(SPR00 + FG_BLUE) '--rain
    clsc(SPR00 + FG_WHITE) '--rain
    FOR j=0 to 3
        '--I'm using GROM cards, I have to multiply by 8 to convert IntyBasic strings to card
        SPRITE j, 54+j*16 + VISIBLE + ZOOMX2, 40 + ZOOMY4,  RainText(j)*8 + SPR_CYAN
        SPRITE j+4, 52+j*16 + VISIBLE + ZOOMX2, 42 + ZOOMY4,  RainText(j)*8 + SPR_BLUE  + BEHIND
    NEXT j

mainloop:
    rain=(rain - 1) AND $7
    DEFINE 0,1,VARPTR RainBitmap(rain)
    FOR j=0 to 6:WAIT:NEXT j
GOTO mainloop

'RainText: DATA "Rain"
RainText: DATA "Snow"

RainBitmap:
BITMAP "        "   '0
BITMAP "        "   '1
BITMAP "        "   '2
BITMAP "      x "   '3
BITMAP "       x"   '4
BITMAP "        "   '5
BITMAP "        "   '6
BITMAP " x      "   '7
BITMAP "  x     "   '8
BITMAP "        "   '9
BITMAP "        "   'A
BITMAP "    x   "   'B
BITMAP "     x  "   'C
BITMAP "        "   'D
BITMAP "        "   'E
BITMAP "        "   'F
BITMAP "        "   '10
BITMAP "        "   '11

 

Snow? Now we're talkin!

  • Like 2
Link to comment
Share on other sites
  • 2 weeks later...
nanochess Quadrunner

+nanochess

Posted
Posted

Ok, I've heard the call of catsfolly :)

 

I've decided to work in the basis of rain columns, the first try was too fast, it looked more like road lines, so after a little experimentation I've discovered it looks better if you can see the line "falling"

 

The animation for rain lines is using GRAM redefinition, the lines could be made longer possibly looking better, currently the streak is 4 rows and repeated. There is a random number chance to draw a different column with the line in different position.

 

I've made a tiny forest in the background using MOBs with palm trees and priority bit enabled, it doesn't look like palm trees, so it's a forest :grin:

 

The lightning was a small last minute add-on.

 

The GIF loses a lots of frames, it's better in emulator.

 

(click to animate)

post-30245-0-64350500-1491863778_thumb.gif

rain.bas

  • Like 7
Link to comment
Share on other sites
First Spear River Patroller

First Spear

Posted
  • Author
Posted

Of course, now I need to ask about the lightning effect. You're not really drawing anything, just making the screen flash with a MODE trick. Can you explain how that works?

 

And thanks to you and Catsfolly and Mmarmero for the rain ideas! :)

 

 

 

Ok, I've heard the call of catsfolly :)

 

I've decided to work in the basis of rain columns, the first try was too fast, it looked more like road lines, so after a little experimentation I've discovered it looks better if you can see the line "falling"

 

The animation for rain lines is using GRAM redefinition, the lines could be made longer possibly looking better, currently the streak is 4 rows and repeated. There is the chance to draw a different column with the line in different position.

 

I've made a tiny forest in the background using MOBs with palm trees and priority bit enabled, it doesn't look like palm trees, so it's a forest :grin:

 

The lightning was a small last minute add-on.

 

The GIF loses a lots of frames, it's better in emulator.

 

(click to animate)

attachicon.gifmvi_0010.gif

  • Like 1
Link to comment
Share on other sites
nanochess Quadrunner

+nanochess

Posted
Posted

Of course, now I need to ask about the lightning effect. You're not really drawing anything, just making the screen flash with a MODE trick. Can you explain how that works?

 

And thanks to you and Catsfolly and Mmarmero for the rain ideas! :)

 

 

 

 

In Color Stack mode there is always a background color choosen from one of 4 values, but if you don't use the Advance bit then it's a single color.

 

So switching the colors makes a great lightning effect.

 

The cycling for lightning is 1-7-0-7 with each color changed every 2 frames.

  • Like 4
Link to comment
Share on other sites
Kiwi River Patroller

Kiwi

Posted
Posted

This my attempt. I wanted to see how much a 16 height MOB at maximum size fills the screen. I'm multiplexing 2 sprites to fill the screen since the game reserved 1 sprite for the main char and 5 sprites for the various object like enemies.

 

post-24767-0-63844800-1491966575_thumb.gif gifeo

 

Here's the code how it works.

if MagicID=4 AND MP>=magicdrain then 
MP=MP-magicdrain
MagicX=20
MagicY=16
MagicX2=80

gosub DrawMP
for x=0 to 200
sprite 1,$600+MagicX,$0380+MagicY,$1971
sprite 2,$600+MagicX2,$0380+MagicY,$1971
i=x%32
if i=0 then define 46,2,MagicStarRain0
if i=4 then define 46,2,MagicStarRain1
if i=8 then define 46,2,MagicStarRain2
if i=12 then define 46,2,MagicStarRain3
if i=16 then define 46,2,MagicStarRain4
if i=20 then define 46,2,MagicStarRain5
if i=24 then define 46,2,MagicStarRain6
if i=28 then define 46,2,MagicStarRain7
i=x%4
if i=0 then MagicX=10:MagicX2=90
if i=1 then MagicX=30:MagicX2=110
if i=2 then MagicX=50:MagicX2=130
if i=3 then MagicX=70:MagicX2=150

wait
next x

MagicX=0
MagicY=0
MagicX2=0

x=15:i=0:gosub MagicHitAt
x=15:i=1:gosub MagicHitAt
x=15:i=2:gosub MagicHitAt
x=15:i=3:gosub MagicHitAt
x=15:i=4:gosub MagicHitAt

end if
  • Like 3
Link to comment
Share on other sites
  • 2 weeks later...
DZ-Jay Quadrunner

+DZ-Jay

Posted
Posted

Ok, I've heard the call of catsfolly :)

 

I've decided to work in the basis of rain columns, the first try was too fast, it looked more like road lines, so after a little experimentation I've discovered it looks better if you can see the line "falling"

 

The animation for rain lines is using GRAM redefinition, the lines could be made longer possibly looking better, currently the streak is 4 rows and repeated. There is a random number chance to draw a different column with the line in different position.

 

I've made a tiny forest in the background using MOBs with palm trees and priority bit enabled, it doesn't look like palm trees, so it's a forest :grin:

 

The lightning was a small last minute add-on.

 

The GIF loses a lots of frames, it's better in emulator.

 

(click to animate)

attachicon.gifmvi_0010.gif

 

I get an assembler error:

0x50BA                  T2:
				;[26] 	SPRITE c,$0708 + c * 20 + RANDOM(,$0288 + RANDOM(20) + 50,$2804+8*8
			;	SRCFILE "rain.bas",26
				; macro must be non-empty, but a comment works fine.
				MVII #Q1,R0
asm/rain.asm:1701: ERROR - undefined symbol  Q1
Link to comment
Share on other sites
catsfolly Dragonstomper

catsfolly

Posted
Posted

 

 

I get an assembler error:

0x50BA                  T2:
				;[26] 	SPRITE c,$0708 + c * 20 + RANDOM(,$0288 + RANDOM(20) + 50,$2804+8*8
			;	SRCFILE "rain.bas",26
				; macro must be non-empty, but a comment works fine.
				MVII #Q1,R0
asm/rain.asm:1701: ERROR - undefined symbol  Q1

 

It compiles fine for me.

 

Are you by any chance using a version of Intybasic older than version 1.2.3 (the first version to allow an expression for a mob index)? The "c" variable is the only variable I see in that line...

 

 

Catsfolly

  • Like 1
Link to comment
Share on other sites
DZ-Jay Quadrunner

+DZ-Jay

Posted
Posted

 

It compiles fine for me.

 

Are you by any chance using a version of Intybasic older than version 1.2.3 (the first version to allow an expression for a mob index)? The "c" variable is the only variable I see in that line...

 

 

Catsfolly

I am using the version available when I last updates the SDK. I'll confirm which one when I get home, just in case.

Link to comment
Share on other sites
catsfolly Dragonstomper

catsfolly

Posted
Posted (edited)

It compiles fine but I get "Warning: label 'START_DEMO' defined but never used" using v1.2.8

 

Yeah, recent versions of IntyBasic give a lot of warnings if a label is defined but not actually referenced in the code.

 

It's a little annoying, but sometimes it helps to find a bug.

 

Generally I just put "rem" in front of my unused labels to get rid of the warnings, and then "unrem" them if I actually need them...

 

Catsfolly

Edited by catsfolly
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
 Share
Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.
AtariAge
Forums
Store
General
Follow AtariAge

Copyright ©1998-2023 AtariAge

×
×
  • Create New...