Uminva for freebasic

This is remake of classic msx game, which was on one of machine language game making book.
Original was just a "shoot until all energy is gone" type game.

I added, changed, and improved many stuff without changing core gameplay of original.

I added stage theme and bonus stage.
Player flies through ocean and forest and shoot aliens.
Aliens will fly toward the player.
Any aliens that get past player will attack player's tank and drain energy.
Player can recover some energy by shooting energy capsule.

On bonus stage, there is no penelty if you miss the falling aliens.(they just fall. not onto player's tank)

I also added chain combo. 
When player hits alien continuously without making mistake, chain counter increases.
When player makes a mistake (shooting empty air), chain breaks and bonus score is awarded (chain x 100pts)
When player hits energy capsule, chain doesn't break.

To make thing more interesting, the small crosshair that helps the aiming...
It will be gone after few stages.

The 3rd mouse button will be treated as Esc key.
It will open up quit menu (if quick_quit is enabled, it will just end the game)
so, player can play and quit the game using only a mouse.

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I also included original UmInva for MSX computer.

UMINVA.BAS is source code.

UMINVA.DSK is a Disk file that can be used by emulator such as BlueMSX.
(dsk file contains autoexec.bat and it will run uminva automatically.)

my remake is based on "no FAST SHOT" mode and "speed 10".
I used 2 sound effect(laser and explosion) and explosion sprites data from original.

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credits:

Sho Endo - original author of Uminva
JawsV - dot artist
ChangeV - programmer
