Testing using ctypes to use glfw

gltest.py

#Some testing

# Run this script with python 3
# Use the interactive mode, like:
# $ python3 -i gltest.py
# You need to have the glfw and of course GL runtimes
# Once you start the script you get a window
# You will also get the python interactive prompt in the terminal you started
# the script in
# Here you can adjust variables sx, sy, sr and s and directly observe the effect
# The rending loop is in another thread
# The render loop exits either on ctrl+c in the terminal or if the window is closed
# Closing the window is the better way since it will clean up more things



import ctypes, time, threading, math

glfw = ctypes.CDLL('libglfw.so')
gl = ctypes.CDLL('libGL.so')

void_pointer = ctypes.POINTER(None)
int_pointer = ctypes.POINTER(ctypes.c_int)



glfwCreateWindow = glfw.glfwCreateWindow
glfwInit = glfw.glfwInit
glfwMakeContextCurrent = glfw.glfwMakeContextCurrent
glfwGetFramebufferSize = glfw.glfwGetFramebufferSize
glfwSwapBuffers = glfw.glfwSwapBuffers
glfwPollEvents = glfw.glfwPollEvents

glBindTexture = gl.glBindTexture

glBindTexture.argtypes= [ctypes.c_int, ctypes.c_int]

glClear = gl.glClear
glBegin = gl.glBegin
glEnd = gl.glEnd
glVertex3f = gl.glVertex3f

glGenTextures = gl.glGenTextures

glGenTextures.argtypes = [ctypes.c_int, ctypes.POINTER(ctypes.c_int)]

glColor4f = gl.glColor4f
glfwWindowShouldClose = glfw.glfwWindowShouldClose
glfwDestroyWindow = glfw.glfwDestroyWindow

glfwDestroyWindow.argtypes = [void_pointer]
glfwTerminate = glfw.glfwTerminate

glfwWindowShouldClose.argtypes = [void_pointer]

glColor4f.argtypes = [ctypes.c_float, ctypes.c_float, ctypes.c_float, ctypes.c_float]

glViewport = gl.glViewport
glOrtho = gl.glOrtho

glOrtho.argtypes =[ctypes.c_double,ctypes.c_double, ctypes.c_double, ctypes.c_double, ctypes.c_double, ctypes.c_double]

glMatrixMode = gl.glMatrixMode

glMatrixMode.argtypes = [ctypes.c_int]
glLoadIdentity = gl.glLoadIdentity

glViewport.argtypes = [ctypes.c_int, ctypes.c_int, ctypes.c_int, ctypes.c_int]

glVertex3f.argtypes = [ctypes.c_float, ctypes.c_float, ctypes.c_float]

glTexCoord2f = gl.glTexCoord2f
glTexCoord2f.argtypes = [ctypes.c_float, ctypes.c_float]

glTexImage2D = gl.glTexImage2D
glTexImage2D.argtypes = [ctypes.c_int, ctypes.c_int, ctypes.c_int, ctypes.c_int, ctypes.c_int, ctypes.c_int, ctypes.c_int, ctypes.c_int, void_pointer]

glfwCreateWindow.restype = void_pointer
glfwCreateWindow.argtypes = [ctypes.c_int, ctypes.c_int, ctypes.c_char_p, void_pointer, void_pointer]

glfwMakeContextCurrent.argtypes = [void_pointer]

glfwGetFramebufferSize.argtypes = [void_pointer, int_pointer, int_pointer]

glEnable = gl.glEnable
glEnable.argtypes = [ctypes.c_int]

glfwSwapBuffers.argtypes = [void_pointer]

glClear.argtypes = [ctypes.c_int]


gl.GL_COLOR_BUFFER_BIT = ctypes.c_int(0x00004000)
gl.GL_QUADS = ctypes.c_int(0x0007)


gl.GL_MATRIX_MODE = ctypes.c_int(0x0BA0)
gl.GL_MODELVIEW = ctypes.c_int(0x1700)
gl.GL_PROJECTION = ctypes.c_int(0x1701)
gl.GL_TEXTURE = ctypes.c_int(0x1702)


gl.GL_BLEND = ctypes.c_int(0x0BE2)
gl.GL_BLEND_SRC = ctypes.c_int(0x0BE1)
gl.GL_BLEND_DST = ctypes.c_int(0x0BE0)
gl.GL_ZERO = ctypes.c_int(0)
gl.GL_ONE = ctypes.c_int(1)
gl.GL_SRC_COLOR = ctypes.c_int(0x0300)
gl.GL_ONE_MINUS_SRC_COLOR = ctypes.c_int(0x0301)
gl.GL_SRC_ALPHA = ctypes.c_int(0x0302)
gl.GL_ONE_MINUS_SRC_ALPHA = ctypes.c_int(0x0303)
gl.GL_DST_ALPHA = ctypes.c_int(0x0304)
gl.GL_ONE_MINUS_DST_ALPHA = ctypes.c_int(0x0305)
gl.GL_DST_COLOR = ctypes.c_int(0x0306)
gl.GL_ONE_MINUS_DST_COLOR = ctypes.c_int(0x0307)
gl.GL_SRC_ALPHA_SATURATE = ctypes.c_int(0x0308)


gl.GL_TEXTURE_ENV = ctypes.c_int(0x2300)
gl.GL_TEXTURE_ENV_MODE = ctypes.c_int(0x2200)
gl.GL_TEXTURE_1D = ctypes.c_int(0x0DE0)
gl.GL_TEXTURE_2D = ctypes.c_int(0x0DE1)
gl.GL_TEXTURE_WRAP_S = ctypes.c_int(0x2802)
gl.GL_TEXTURE_WRAP_T = ctypes.c_int(0x2803)
gl.GL_TEXTURE_MAG_FILTER = ctypes.c_int(0x2800)
gl.GL_TEXTURE_MIN_FILTER = ctypes.c_int(0x2801)
gl.GL_TEXTURE_ENV_COLOR = ctypes.c_int(0x2201)
gl.GL_TEXTURE_GEN_S = ctypes.c_int(0x0C60)
gl.GL_TEXTURE_GEN_T = ctypes.c_int(0x0C61)
gl.GL_TEXTURE_GEN_R = ctypes.c_int(0x0C62)
gl.GL_TEXTURE_GEN_Q = ctypes.c_int(0x0C63)
gl.GL_TEXTURE_GEN_MODE = ctypes.c_int(0x2500)
gl.GL_TEXTURE_BORDER_COLOR = ctypes.c_int(0x1004)
gl.GL_TEXTURE_WIDTH = ctypes.c_int(0x1000)
gl.GL_TEXTURE_HEIGHT = ctypes.c_int(0x1001)
gl.GL_TEXTURE_BORDER = ctypes.c_int(0x1005)
gl.GL_TEXTURE_COMPONENTS = ctypes.c_int(0x1003)
gl.GL_TEXTURE_RED_SIZE = ctypes.c_int(0x805C)
gl.GL_TEXTURE_GREEN_SIZE = ctypes.c_int(0x805D)
gl.GL_TEXTURE_BLUE_SIZE = ctypes.c_int(0x805E)
gl.GL_TEXTURE_ALPHA_SIZE = ctypes.c_int(0x805F)
gl.GL_TEXTURE_LUMINANCE_SIZE = ctypes.c_int(0x8060)
gl.GL_TEXTURE_INTENSITY_SIZE = ctypes.c_int(0x8061)
gl.GL_NEAREST_MIPMAP_NEAREST = ctypes.c_int(0x2700)
gl.GL_NEAREST_MIPMAP_LINEAR = ctypes.c_int(0x2702)
gl.GL_LINEAR_MIPMAP_NEAREST = ctypes.c_int(0x2701)
gl.GL_LINEAR_MIPMAP_LINEAR = ctypes.c_int(0x2703)
gl.GL_OBJECT_LINEAR = ctypes.c_int(0x2401)
gl.GL_OBJECT_PLANE = ctypes.c_int(0x2501)
gl.GL_EYE_LINEAR = ctypes.c_int(0x2400)
gl.GL_EYE_PLANE = ctypes.c_int(0x2502)
gl.GL_SPHERE_MAP = ctypes.c_int(0x2402)
gl.GL_DECAL = ctypes.c_int(0x2101)
gl.GL_MODULATE = ctypes.c_int(0x2100)
gl.GL_NEAREST = ctypes.c_int(0x2600)
gl.GL_REPEAT = ctypes.c_int(0x2901)
gl.GL_CLAMP = ctypes.c_int(0x2900)
gl.GL_S = ctypes.c_int(0x2000)
gl.GL_T = ctypes.c_int(0x2001)
gl.GL_R = ctypes.c_int(0x2002)
gl.GL_Q = ctypes.c_int(0x2003)

gl.GL_RESCALE_NORMAL = ctypes.c_int(0x803A)
gl.GL_CLAMP_TO_EDGE = ctypes.c_int(0x812F)
gl.GL_MAX_ELEMENTS_VERTICES = ctypes.c_int(0x80E8)
gl.GL_MAX_ELEMENTS_INDICES = ctypes.c_int(0x80E9)
gl.GL_BGR = ctypes.c_int(0x80E0)
gl.GL_BGRA = ctypes.c_int(0x80E1)
gl.GL_UNSIGNED_BYTE_3_3_2 = ctypes.c_int(0x8032)
gl.GL_UNSIGNED_BYTE_2_3_3_REV = ctypes.c_int(0x8362)
gl.GL_UNSIGNED_SHORT_5_6_5 = ctypes.c_int(0x8363)
gl.GL_UNSIGNED_SHORT_5_6_5_REV = ctypes.c_int(0x8364)
gl.GL_UNSIGNED_SHORT_4_4_4_4 = ctypes.c_int(0x8033)
gl.GL_UNSIGNED_SHORT_4_4_4_4_REV = ctypes.c_int(0x8365)
gl.GL_UNSIGNED_SHORT_5_5_5_1 = ctypes.c_int(0x8034)
gl.GL_UNSIGNED_SHORT_1_5_5_5_REV = ctypes.c_int(0x8366)
gl.GL_UNSIGNED_INT_8_8_8_8 = ctypes.c_int(0x8035)
gl.GL_UNSIGNED_INT_8_8_8_8_REV = ctypes.c_int(0x8367)
gl.GL_UNSIGNED_INT_10_10_10_2 = ctypes.c_int(0x8036)
gl.GL_UNSIGNED_INT_2_10_10_10_REV = ctypes.c_int(0x8368)
gl.GL_LIGHT_MODEL_COLOR_CONTROL = ctypes.c_int(0x81F8)
gl.GL_SINGLE_COLOR = ctypes.c_int(0x81F9)
gl.GL_SEPARATE_SPECULAR_COLOR = ctypes.c_int(0x81FA)
gl.GL_TEXTURE_MIN_LOD = ctypes.c_int(0x813A)
gl.GL_TEXTURE_MAX_LOD = ctypes.c_int(0x813B)
gl.GL_TEXTURE_BASE_LEVEL = ctypes.c_int(0x813C)
gl.GL_TEXTURE_MAX_LEVEL = ctypes.c_int(0x813D)
gl.GL_SMOOTH_POINT_SIZE_RANGE = ctypes.c_int(0x0B12)
gl.GL_SMOOTH_POINT_SIZE_GRANULARITY = ctypes.c_int(0x0B13)
gl.GL_SMOOTH_LINE_WIDTH_RANGE = ctypes.c_int(0x0B22)
gl.GL_SMOOTH_LINE_WIDTH_GRANULARITY = ctypes.c_int(0x0B23)
gl.GL_ALIASED_POINT_SIZE_RANGE = ctypes.c_int(0x846D)
gl.GL_ALIASED_LINE_WIDTH_RANGE = ctypes.c_int(0x846E)
gl.GL_PACK_SKIP_IMAGES = ctypes.c_int(0x806B)
gl.GL_PACK_IMAGE_HEIGHT = ctypes.c_int(0x806C)
gl.GL_UNPACK_SKIP_IMAGES = ctypes.c_int(0x806D)
gl.GL_UNPACK_IMAGE_HEIGHT = ctypes.c_int(0x806E)
gl.GL_TEXTURE_3D = ctypes.c_int(0x806F)
gl.GL_PROXY_TEXTURE_3D = ctypes.c_int(0x8070)
gl.GL_TEXTURE_DEPTH = ctypes.c_int(0x8071)
gl.GL_TEXTURE_WRAP_R = ctypes.c_int(0x8072)
gl.GL_MAX_3D_TEXTURE_SIZE = ctypes.c_int(0x8073)
gl.GL_TEXTURE_BINDING_3D = ctypes.c_int(0x806A)


gl.GL_NONE = ctypes.c_int(0)
gl.GL_LEFT = ctypes.c_int(0x0406)
gl.GL_RIGHT = ctypes.c_int(0x0407)
gl.GL_FRONT_LEFT = ctypes.c_int(0x0400)
gl.GL_FRONT_RIGHT = ctypes.c_int(0x0401)
gl.GL_BACK_LEFT = ctypes.c_int(0x0402)
gl.GL_BACK_RIGHT = ctypes.c_int(0x0403)
gl.GL_AUX0 = ctypes.c_int(0x0409)
gl.GL_AUX1 = ctypes.c_int(0x040A)
gl.GL_AUX2 = ctypes.c_int(0x040B)
gl.GL_AUX3 = ctypes.c_int(0x040C)
gl.GL_COLOR_INDEX = ctypes.c_int(0x1900)
gl.GL_RED = ctypes.c_int(0x1903)
gl.GL_GREEN = ctypes.c_int(0x1904)
gl.GL_BLUE = ctypes.c_int(0x1905)
gl.GL_ALPHA = ctypes.c_int(0x1906)
gl.GL_LUMINANCE = ctypes.c_int(0x1909)
gl.GL_LUMINANCE_ALPHA = ctypes.c_int(0x190A)
gl.GL_ALPHA_BITS = ctypes.c_int(0x0D55)
gl.GL_RED_BITS = ctypes.c_int(0x0D52)
gl.GL_GREEN_BITS = ctypes.c_int(0x0D53)
gl.GL_BLUE_BITS = ctypes.c_int(0x0D54)
gl.GL_INDEX_BITS = ctypes.c_int(0x0D51)
gl.GL_SUBPIXEL_BITS = ctypes.c_int(0x0D50)
gl.GL_AUX_BUFFERS = ctypes.c_int(0x0C00)
gl.GL_READ_BUFFER = ctypes.c_int(0x0C02)
gl.GL_DRAW_BUFFER = ctypes.c_int(0x0C01)
gl.GL_DOUBLEBUFFER = ctypes.c_int(0x0C32)
gl.GL_STEREO = ctypes.c_int(0x0C33)
gl.GL_BITMAP = ctypes.c_int(0x1A00)
gl.GL_COLOR = ctypes.c_int(0x1800)
gl.GL_DEPTH = ctypes.c_int(0x1801)
gl.GL_STENCIL = ctypes.c_int(0x1802)
gl.GL_DITHER = ctypes.c_int(0x0BD0)
gl.GL_RGB = ctypes.c_int(0x1907)
gl.GL_RGBA = ctypes.c_int(0x1908)

gl.GL_BYTE = ctypes.c_int(0x1400)
gl.GL_UNSIGNED_BYTE = ctypes.c_int(0x1401)
gl.GL_SHORT = ctypes.c_int(0x1402)
gl.GL_UNSIGNED_SHORT = ctypes.c_int(0x1403)
gl.GL_INT = ctypes.c_int(0x1404)
gl.GL_UNSIGNED_INT = ctypes.c_int(0x1405)
gl.GL_FLOAT = ctypes.c_int(0x1406)
gl.GL_2_BYTES = ctypes.c_int(0x1407)
gl.GL_3_BYTES = ctypes.c_int(0x1408)
gl.GL_4_BYTES = ctypes.c_int(0x1409)
gl.GL_DOUBLE = ctypes.c_int(0x140A)

gl.GL_FOG = ctypes.c_int(0x0B60)
gl.GL_FOG_MODE = ctypes.c_int(0x0B65)
gl.GL_FOG_DENSITY = ctypes.c_int(0x0B62)
gl.GL_FOG_COLOR = ctypes.c_int(0x0B66)
gl.GL_FOG_INDEX = ctypes.c_int(0x0B61)
gl.GL_FOG_START = ctypes.c_int(0x0B63)
gl.GL_FOG_END = ctypes.c_int(0x0B64)
gl.GL_LINEAR = ctypes.c_int(0x2601)
gl.GL_EXP = ctypes.c_int(0x0800)
gl.GL_EXP2 = ctypes.c_int(0x0801)


glTexParameteri = gl.glTexParameteri
glTexParameteri.argtypes = [ctypes.c_int, ctypes.c_int]


glRotatef = gl.glRotatef
glTranslatef =gl.glTranslatef

glRotatef.argtypes = [ctypes.c_float, ctypes.c_float, ctypes.c_float, ctypes.c_float]
glTranslatef.argtypes = [ctypes.c_float, ctypes.c_float, ctypes.c_float]

assert glfwInit() == 1, 'Failed to init GLFW'

w = glfwCreateWindow(640, 480, b"Hello World!", None, None)
assert w, 'Failed to create window'


sx = 100
sy = 100
sr = 45
s = 100



def render_test_loop(window):
	glfwMakeContextCurrent(window)
	width = ctypes.c_int(0)
	height = ctypes.c_int(0)




	textures = (ctypes.c_int * 1)(0)
	glGenTextures(1, textures)

	test = (ctypes.c_char * 4*64*64)()

	glBindTexture(gl.GL_TEXTURE_2D, textures[0])
	glTexImage2D(gl.GL_TEXTURE_2D, 0,gl.GL_RGBA, 64, 64, 0, gl.GL_RGBA, gl.GL_UNSIGNED_BYTE, test)
	glTexParameteri(gl.GL_TEXTURE_2D, gl.GL_TEXTURE_MAG_FILTER, gl.GL_NEAREST)
	glTexParameteri(gl.GL_TEXTURE_2D, gl.GL_TEXTURE_MIN_FILTER, gl.GL_LINEAR)


	glEnable(gl.GL_TEXTURE_2D)
	glEnable(gl.GL_BLEND)
	

	while not glfwWindowShouldClose(window):

		rx = math.sin(time.time())*30+30
		ry = math.cos(time.time())*30+30

		for x in range(64):
			for y in range(64):
				r = int(time.time()*-250 +  (((x-rx)**2 + (y-ry)**2)**0.5) * 30 ) & 0xff
				test[x][y] = r, r, r, 0x80

		glBindTexture(gl.GL_TEXTURE_2D, textures[0])
		glTexImage2D(gl.GL_TEXTURE_2D, 0,gl.GL_RGBA, 64, 64, 0, gl.GL_RGBA, gl.GL_UNSIGNED_BYTE, test)



		glfwGetFramebufferSize(window, int_pointer(width), int_pointer(height))

		glViewport(0,0, width.value-1, height.value-1)
		glMatrixMode(gl.GL_PROJECTION)
		glLoadIdentity()
		glOrtho(0, width.value-1, height.value-1, 0,0,1)
		glMatrixMode(gl.GL_MODELVIEW)
		glLoadIdentity()


		glClear(gl.GL_COLOR_BUFFER_BIT)

		glColor4f(1.0, 1.0, 1.0, 1.0)

		glTranslatef(sx, sy, 0)
		glRotatef(sr, 0, 0, 1)

		glBegin(gl.GL_QUADS)
		glVertex3f(-s, -s, 0)
		glTexCoord2f(0, 0)
		glVertex3f(s, -s, 0)
		glTexCoord2f(1, 0)
		glVertex3f(s, s, 0)
		glTexCoord2f(1, 1)
		glVertex3f(-s, s, 0)
		glTexCoord2f(0, 1)
		glEnd()

		glfwSwapBuffers(window)
		glfwPollEvents()


	glfwDestroyWindow(window)	
	glfwTerminate()

t = threading.Thread(target=render_test_loop, args=(w,))
t.start()