R100P0610A02 - assembly/02
This is a part of R100P0917A00 .
Now this is where I get cocky. I now know how to use libraries from my assembler… so what’s stopping me from using GLFW? Now kids, let me remind you – GLFW is a C library. It’s not meant to be used from assembly. Well, I mean it could be, but it’s sort of pointless to use from assembly. That sure didn’t stop me, though. This was also made September 7th, 2023.
Now that I’m using GLFW, you’ll have to do some stuff with your compiler and
machine. On my Linux machine, it compiles with: gcc -lglfw -lOpenGL -o program
main.s.
.global main
.text
title:
.string "GLFW from ASM: Why Not"
main:
push %rbx ; since we are already using rbx below, ensure stack alignment
call glfwInit
cmp $1, %rax
jne init_fail ; jump straight to end on failure (return code)
; glfwCreateWindow(int width, int height, char *title, void *monitor, void *share)
mov $640, %edi
mov $480, %esi
lea title(%rip), %rdx
xor %ecx, %ecx
xor %r8d, %r8d
call glfwCreateWindow
mov %rax, %rbx ; store window into rbx
mov %rax, %rdi
call glfwMakeContextCurrent
loop:
; glClear(GL_COLOR_BUFFER_BIT)
mov $0x00004000, %rdi
call glClear
mov %rbx, %rdi
call glfwSwapBuffers
call glfwPollEvents
; glfwWindowShouldClose(void *window)
mov %rbx, %rdi
call glfwWindowShouldClose
test %eax, %eax
je loop
xor %eax, %eax
init_fail:
pop %rbx
ret