问题描述
我试图使用8086汇编器绘制一个圆.我尝试使用中点圆算法,该算法由于某种原因而令人遗憾地导致绘制了一个倾斜的正方形(屏幕截图)以下).作为参考,我重写了python中的算法,并成功地画了一个圆.
I was trying to draw a circle using 8086 assembler. I tried utilizing the midpoint circle algorithm which sadly resulted in drawing a tilted square for some reason (screenshots below). For reference, I rewrote the algorithm in python and managed to draw a circle without a problem.
我感觉我的负数操作有问题,但我一生都无法解决,因为Turbo Debugger告诉我的是什么也没有.你能指导我正确的方向吗?我附上以下代码:
I have a feeling that there is something wrong with my negative numbers manipulation but can't for the life of me figure it out because Turbo Debugger is telling me literally nothing. Could you guide me in the right direction?I enclose the code below:
; Program: graph.asm
.MODEL small
.STACK 256
.DATA
.CODE
jmp start
;=========================================
; Basic program to draw a circle
;=========================================
mode db 18 ;640 x 480
x_center dw 300
y_center dw 200
y_value dw 0
x_value dw 100
decision dw 1
colour db 1 ;1=blue
;=========================================
start:
mov ah,00 ;subfunction 0
mov al,mode ;select mode 18
int 10h ;call graphics interrupt
;==========================
mov bx, x_value
sub decision, bx
mov al,colour ;colour goes in al
mov ah,0ch
drawcircle:
mov al,colour ;colour goes in al
mov ah,0ch
mov cx, x_value ;Octonant 1
add cx, x_center ;( x_value + x_center, y_value + y_center)
mov dx, y_value
add dx, y_center
int 10h
mov cx, x_value ;Octonant 4
neg cx
add cx, x_center ;( -x_value + x_center, y_value + y_center)
int 10h
mov cx, y_value ;Octonant 2
add cx, x_center ;( y_value + x_center, x_value + y_center)
mov dx, x_value
add dx, y_center
int 10h
mov cx, y_value ;Octonant 3
neg cx
add cx, x_center ;( -y_value + x_center, x_value + y_center)
int 10h
mov cx, x_value ;Octonant 7
add cx, x_center ;( x_value + x_center, -y_value + y_center)
mov dx, y_value
neg dx
add dx, y_center
int 10h
mov cx, x_value ;Octonant 5
neg cx
add cx, x_center ;( -x_value + x_center, -y_value + y_center)
int 10h
mov cx, y_value ;Octonant 8
add cx, x_center ;( y_value + x_center, -x_value + y_center)
mov dx, x_value
neg dx
add dx, y_center
int 10h
mov cx, y_value ;Octonant 6
neg cx
add cx, x_center ;( -y_value + x_center, -x_value + y_center)
int 10h
inc y_value
condition1:
cmp decision,0
ja condition2
mov cx, y_value
mov ax, 2
imul cx
add cx, 1
inc cx
add decision, cx
mov bx, y_value
mov dx, x_value
cmp bx, dx
ja readkey
jmp drawcircle
condition2:
dec x_value
mov cx, y_value
sub cx, x_value
mov ax, 2
imul cx
inc cx
add decision, cx
mov bx, y_value
mov dx, x_value
cmp bx, dx
ja readkey
jmp drawcircle
;==========================
readkey:
mov ah,00
int 16h ;wait for keypress
;==========================
endd:
mov ah,00 ;again subfunc 0
mov al,03 ;text mode 3
int 10h ;call int
mov ah,04ch
mov al,00 ;end program normally
int 21h
END Start
尝试在汇编器中尝试使用Python
Attempt in AssemblerAttempt in Python
预先感谢您的帮助!
推荐答案
您的汇编代码绘制的正方形来自等式:
the square which is your assembly code drew comes from equation :
|x| + |y| = constant
这意味着您的值不会平方
This means your values are not getting squared
这篇关于使用8086汇编语言绘制圆的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!