4.py

import glfw
from OpenGL.GL import *
import numpy as np

global gComposedM
gComposedM = np.identity(3)

def render(T):
    glClear(GL_COLOR_BUFFER_BIT)
    glLoadIdentity()
    # draw cooridnate
    glBegin(GL_LINES)
    glColor3ub(255, 0, 0)
    glVertex2fv(np.array([0.,0.]))
    glVertex2fv(np.array([1.,0.]))
    glColor3ub(0, 255, 0)
    glVertex2fv(np.array([0.,0.]))
    glVertex2fv(np.array([0.,1.]))
    glEnd()
    # draw triangle
    glBegin(GL_TRIANGLES)
    glColor3ub(255, 255, 255)
    glVertex2fv( (T @ np.array([.0,.5,1.]))[:-1] )
    glVertex2fv( (T @ np.array([.0,.0,1.]))[:-1] )
    glVertex2fv( (T @ np.array([.5,.0,1.]))[:-1] )
    glEnd()

def key_callback(window, key, scancode, action, mods):
    global gComposedM
    if key==glfw.KEY_W:
        if (action==glfw.PRESS or action==glfw.REPEAT):
            T = np.array([[1, 0, 0],
			[0, 0.9, 0],
			[0, 0, 1]])
            gComposedM = T @ gComposedM

    if key==glfw.KEY_E:
        if (action==glfw.PRESS or action==glfw.REPEAT):
            T = np.array([[1, 0, 0],
			[0, 1.1, 0],
			[0, 0, 1]])
            gComposedM = T @ gComposedM

    if key==glfw.KEY_S:
        if (action==glfw.PRESS or action==glfw.REPEAT):
            th = np.radians(10)
            T = np.array([[np.cos(th), -np.sin(th), 0],
			[np.sin(th), np.cos(th), 0],
			[0, 0, 1]])
            gComposedM = T @ gComposedM

    if key==glfw.KEY_D:
        if (action==glfw.PRESS or action==glfw.REPEAT):
            th = np.radians(10)
            T = np.array([[np.cos(th), np.sin(th), 0],
			[-np.sin(th), np.cos(th), 0],
			[0, 0, 1]])
            gComposedM = T @ gComposedM

    if key==glfw.KEY_X:
        if (action==glfw.PRESS or action==glfw.REPEAT):
            T = np.array([[1, 0, 0.1],
			[0, 1, 0],
			[0, 0, 1]])
            gComposedM = T @ gComposedM

    if key==glfw.KEY_C:
        if (action==glfw.PRESS or action==glfw.REPEAT):
            T = np.array([[1, 0, -0.1],
			[0, 1, 0],
			[0, 0, 1]])
            gComposedM = T @ gComposedM

    if key==glfw.KEY_R:
        if (action==glfw.PRESS or action==glfw.REPEAT):
            T = np.array([[-1, 0, 0],
			[0, -1, 0],
			[0, 0, 1]])
            gComposedM = T @ gComposedM

    if key==glfw.KEY_1:
        if (action==glfw.PRESS or action==glfw.REPEAT):
            T = np.identity(3)
            gComposedM = T

def main():
    if not glfw.init():
        return
    window = glfw.create_window(480,480,"A", None,None)
    if not window:
        glfw.terminate()
        return

    glfw.set_key_callback(window, key_callback)

    glfw.make_context_current(window)

    glfw.swap_interval(1)

    global gComposedM
    gComposedM = np.identity(3)

    while not glfw.window_should_close(window):
        glfw.poll_events()
        
        render(gComposedM)

        glfw.swap_buffers(window)

    glfw.terminate()

if __name__ == "__main__":
    main()