ex_texture_quad.py

# coding=utf-8
"""Texture Quad in 2D"""

import glfw
from OpenGL.GL import *
import OpenGL.GL.shaders
import numpy as np
import sys
import os.path
sys.path.append(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
import grafica.transformations as tr
import grafica.basic_shapes as bs
import grafica.easy_shaders as es
from grafica.assets_path import getAssetPath

__author__ = "Daniel Calderon"
__license__ = "MIT"


# A class to store the application control
class Controller:
    def __init__(self):
        self.fillPolygon = True


# global controller as communication with the callback function
controller = Controller()


def on_key(window, key, scancode, action, mods):

    if action != glfw.PRESS:
        return
    
    global controller

    if key == glfw.KEY_SPACE:
        controller.fillPolygon = not controller.fillPolygon

    elif key == glfw.KEY_ESCAPE:
        glfw.set_window_should_close(window, True)

    else:
        print('Unknown key')


if __name__ == "__main__":

    # Initialize glfw
    if not glfw.init():
        glfw.set_window_should_close(window, True)

    width = 600
    height = 600

    window = glfw.create_window(width, height, "Textured Quad", None, None)

    if not window:
        glfw.terminate()
        glfw.set_window_should_close(window, True)

    glfw.make_context_current(window)

    # Connecting the callback function 'on_key' to handle keyboard events
    glfw.set_key_callback(window, on_key)

    # A simple shader program with position and texture coordinates as inputs.
    pipeline = es.SimpleTextureTransformShaderProgram()
    
    # Telling OpenGL to use our shader program
    glUseProgram(pipeline.shaderProgram)

    # Setting up the clear screen color
    glClearColor(0.25, 0.25, 0.25, 1.0)

    # Creating shapes on GPU memory
    shape = bs.createTextureQuad(2, 2)
    gpuShape = es.GPUShape().initBuffers()
    pipeline.setupVAO(gpuShape)
    gpuShape.fillBuffers(shape.vertices, shape.indices, GL_STATIC_DRAW)
    gpuShape.texture = es.textureSimpleSetup(
        getAssetPath("bricks.jpg"), GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE, GL_LINEAR, GL_LINEAR)

    while not glfw.window_should_close(window):
        # Using GLFW to check for input events
        glfw.poll_events()

        if (controller.fillPolygon):
            glPolygonMode(GL_FRONT_AND_BACK, GL_FILL)
        else:
            glPolygonMode(GL_FRONT_AND_BACK, GL_LINE)

        # Clearing the screen in both, color and depth
        glClear(GL_COLOR_BUFFER_BIT)

        # Drawing the shapes        
        glUniformMatrix4fv(glGetUniformLocation(pipeline.shaderProgram, "transform"), 1, GL_TRUE, tr.uniformScale(1.5))
        pipeline.drawCall(gpuShape)

        # Once the render is done, buffers are swapped, showing only the complete scene.
        glfw.swap_buffers(window)
    
    # freeing GPU memory
    gpuShape.clear()

    glfw.terminate()