Hi All,
I was wondering if I could get some help with this. I'm a noob trying to learn some Python and OpenGL with the GLM Math
lib. I'd like to eventually move back to Cpp for graphics programming but was getting a bit overwhelmed. I've given this
a good try and am either making some small mistakes or am completely missing the mark. I'm getting a green screen and no cube
with no errors. I've left this as functions instead of one class because with python at the moment I'm just starting to code
classes. I've commented out the shader compilation checks as it was killing my program. I probably have errors there I'm
about 3 days into GLSL
. Thanks hopefully this might help others with a similar issue. (Ex. Page 124 OpenGl Super Bible)
I was wondering if I could get some help with this. I'm a noob trying to learn some Python and OpenGL with the GLM Math
lib. I'd like to eventually move back to Cpp for graphics programming but was getting a bit overwhelmed. I've given this
a good try and am either making some small mistakes or am completely missing the mark. I'm getting a green screen and no cube
with no errors. I've left this as functions instead of one class because with python at the moment I'm just starting to code
classes. I've commented out the shader compilation checks as it was killing my program. I probably have errors there I'm
about 3 days into GLSL
. Thanks hopefully this might help others with a similar issue. (Ex. Page 124 OpenGl Super Bible)from OpenGL.GL import shaders
from OpenGL.arrays import vbo
from OpenGL.GL import *
from OpenGL.raw.GL.ARB.vertex_array_object import glGenVertexArrays, glBindVertexArray
from datetime import datetime
import pygame
import glm
import numpy as np
import ctypes
import math as m
import os
#GLSL
def startup():
vertex_shader_source = """
#version 430 core
in vec4 position;
out VS_OUT
{
vec4 color;
} vs_out;
uniform mat4 mv_matrix;
uniform mat4 proj_matrix;
void main(void)
{
gl_Position = proj_matrix * mv_matrix * position;
vs_out.color = position * 2.0 + vec4(0.5, 0.5, 0.5, 0.0);
}
"""
fragment_shader_source = """
#version 430 core
out vec4 color;
in VS_OUT
{
vec4 color;
} fs_in;
void main(void)
{
color = fs_in.color;
}
"""
# --- Create a program
program = glCreateProgram()
#vertex_shader = GLuint()
vertex_shader = glCreateShader(GL_VERTEX_SHADER)
glShaderSource(vertex_shader, vertex_shader_source)
glCompileShader(vertex_shader)
#result = GL_FALSE
#glGetShaderiv(vertex_shader,GL_COMPILE_STATUS,result)
#if (result!=1): # shader didn't compile
# raise Exception("Couldn't compile shader\nShader compilation Log:\n"+glGetShaderInfoLog(vertex_shader))
#fragment_shader = GLuint()
fragment_shader = glCreateShader(GL_FRAGMENT_SHADER)
glShaderSource(fragment_shader, fragment_shader_source)
glCompileShader(fragment_shader)
#result_fs = glGetShaderiv(fragment_shader,GL_COMPILE_STATUS)
#if (result_fs!=1): # shader didn't compile
# raise Exception("Couldn't compile shader\nShader compilation Log:\n"+glGetShaderInfoLog(fragment_shader))
glAttachShader(program, vertex_shader)
glAttachShader(program, fragment_shader)
glLinkProgram(program)
mv_location = glGetUniformLocation(program, "mv_matrix")
proj_location = glGetUniformLocation(program, "proj_matrix")
# Create VAO and bind it
vertex_array_object = GLuint()
glGenVertexArrays(1, vertex_array_object)
glBindVertexArray(vertex_array_object)
vertex_positions = [-0.25, 0.25, -0.25,
-0.25, -0.25, -0.25,
0.25, -0.25, -0.25,
0.25, -0.25, -0.25,
0.25, 0.25, -0.25,
-0.25, 0.25, -0.25,
0.25, -0.25, -0.25,
0.25, -0.25, 0.25,
0.25, 0.25, -0.25,
0.25, -0.25, 0.25,
0.25, 0.25, 0.25,
0.25, 0.25, -0.25,
0.25, -0.25, 0.25,
-0.25, -0.25, 0.25,
0.25, 0.25, 0.25,
-0.25, -0.25, 0.25,
-0.25, 0.25, 0.25,
0.25, 0.25, 0.25,
-0.25, -0.25, 0.25,
-0.25, -0.25, -0.25,
-0.25, 0.25, 0.25,
-0.25, -0.25, -0.25,
-0.25, 0.25, -0.25,
-0.25, 0.25, 0.25,
-0.25, -0.25, 0.25,
0.25, -0.25, 0.25,
0.25, -0.25, -0.25,
0.25, -0.25, -0.25,
-0.25, -0.25, -0.25,
-0.25, -0.25, 0.25,
-0.25, 0.25, -0.25,
0.25, 0.25, -0.25,
0.25, 0.25, 0.25,
0.25, 0.25, 0.25,
-0.25, 0.25, 0.25,
-0.25, 0.25, -0.25]
vertex_positions = np.array(vertex_positions, dtype=np.float32)
# Generate buffers to hold our vertex_positions
vertex_buffer_object = GLuint()
glGenBuffers(1,vertex_buffer_object)
glBindBuffer(GL_ARRAY_BUFFER, vertex_buffer_object)
glBufferData(GL_ARRAY_BUFFER, len(vertex_positions), vertex_positions, GL_STATIC_DRAW)
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, len(vertex_positions), ctypes.c_void_p(0))
glEnableVertexAttribArray(0);
glEnable(GL_CULL_FACE)
glFrontFace(GL_CW)
glEnable(GL_DEPTH_TEST)
glDepthFunc(GL_LEQUAL)
# --- Clean up now that we don't need these shaders anymore.
glDeleteShader(vertex_shader)
glDeleteShader(fragment_shader)
return program, proj_location, mv_location
def render():
program, proj_location, mv_location = startup()
currentTime = datetime.now().second
green = [0.0, 0.25, 0.0, 1.0]
#one = 1.0
glClearBufferfv(GL_COLOR, 0, green)
#glClearBufferfv(GL_DEPTH, 0, one)
glUseProgram(program)
proj_matrix = glm.perspective(glm.radians(50.0),800/600,0.1,1000.0)
proj_matrix = np.array(proj_matrix, dtype=np.float32)
glUniformMatrix4fv(proj_location, 1, GL_FALSE, proj_matrix)
f = currentTime * m.pi * 0.1
x = glm.mat4()
vectran1 = glm.translate(x, glm.vec3(0.0, 0.0, -4.0))
vectran2 = glm.translate(x, glm.vec3(m.sin(2.1 * f) * 0.5,m.cos(1.7 * f) * 0.5, m.sin(1.3 * f) * m.cos(1.5 * f) * 2.0))
vecrot1 = glm.rotate(x,currentTime * 45.0, glm.vec3(0.0, 1.0, 0.0))
vecrot2 = glm.rotate(x,currentTime * 81.0, glm.vec3(1.0, 0.0, 0.0))
mv_matrix = vectran1 * vectran2 * vecrot1 * vecrot2
mv_matrix = np.array(mv_matrix, dtype=np.float32)
mvp_matrix = mv_matrix * proj_matrix
# Set the model-view and projection matrices
glUniformMatrix4fv(mv_location, 1, GL_FALSE, mv_matrix)
glDrawArrays(GL_TRIANGLES, 0, 36)
#display(shader, vertex_array_object)
def shutdown():
glDeleteVertexArrays()
def main():
pygame.init()
screen = pygame.display.set_mode((800,600), pygame.OPENGL | pygame.DOUBLEBUF)
clock = pygame.time.Clock()
while True:
for event in pygame.event.get():
if event.type == pygame.QUIT:
return
if event.type == pygame.KEYUP and event.key == pygame.K_ESCAPE:
return
startup()
render()
pygame.display.flip()
main()