Relatively simple program drawing a blank screen. Ported from Superbible Opengl 7th ed.
The program is currently drawing a blank screen. Although the textoverlay is working correctly.
Update: Added the use of glGetError to add additional error checking. Though there is no error produced by it. Still a blank screen however.
Update and SUCCESS: The program is now rendering the hdr image perfect. Thanks to Rabbid76 excellent answer. It was also a ktxloader that needed a fix. Thank you.
Expected output is:
support files: hdrexposure_support.zip
ported from: hdrexposure.cpp
source code:
#!/usr/bin/python3
import sys
import time
import ctypes
fullscreen = True
sys.path.append("./shared")
from sbmloader import SBMObject # location of sbm file format loader
from ktxloader import KTXObject # location of ktx file format loader
from textoverlay import OVERLAY_
from shader import shader_load, link_from_shaders
from sbmath import m3dDegToRad, m3dRadToDeg, m3dTranslateMatrix44, m3dRotationMatrix44, \
m3dMultiply, m3dOrtho, m3dPerspective, rotation_matrix, translate, m3dScaleMatrix44, \
scale, m3dLookAt, normalize
try:
from OpenGL.GLUT import *
from OpenGL.GL import *
from OpenGL.GLU import *
from OpenGL.raw.GL.ARB.vertex_array_object import glGenVertexArrays, glBindVertexArray
except:
print ('''
ERROR: PyOpenGL not installed properly.
''')
sys.exit()
import numpy as np
from math import cos, sin
import glm
identityMatrix = [1,0,0,0, 0,1,0,0, 0,0,1,0, 0,0,0,1]
myobject = SBMObject()
ktxobject = KTXObject()
overlay = OVERLAY_()
texture = GLuint(0)
program = GLuint(0)
vao = GLuint(0)
exposure=1.0
vs_source = '''
#version 420 core
void main(void)
{
const vec4 vertices[] = vec4[](vec4(-1.0, -1.0, 0.5, 1.0),
vec4( 1.0, -1.0, 0.5, 1.0),
vec4(-1.0, 1.0, 0.5, 1.0),
vec4( 1.0, 1.0, 0.5, 1.0));
gl_Position = vertices[gl_VertexID];
}
'''
fs_source = '''
#version 430 core
uniform sampler2D s;
uniform float exposure;
out vec4 color;
void main(void)
{
vec4 c = texture(s, gl_FragCoord.xy / vec2(512.0, 512.0));
c.xyz = vec3(1.0) - exp(-c.xyz * exposure);
color = c;
}
'''
def checkGLError():
status = glGetError()
if status != GL_NO_ERROR:
raise RuntimeError('gl error %s' % (status,))
class Scene:
def __init__(self, width, height):
global overlay
global texture
global program
global vao
self.width = width
self.height = height
overlay.init(80, 50)
#// Generate a name for the texture
glGenTextures(1, texture)
#// Load texture from file
texture = ktxobject.ktx_load("treelights_2k.ktx")
#// Now bind it to the context using the GL_TEXTURE_2D binding point
glBindTexture(GL_TEXTURE_2D, texture)
program = glCreateProgram()
fs = glCreateShader(GL_FRAGMENT_SHADER)
glShaderSource(fs, fs_source)
glCompileShader(fs)
if not glGetShaderiv(fs, GL_COMPILE_STATUS):
print( 'compile error:' )
print( glGetShaderInfoLog(fs) )
vs = glCreateShader(GL_VERTEX_SHADER)
glShaderSource(vs, vs_source)
glCompileShader(vs)
if not glGetShaderiv(vs, GL_COMPILE_STATUS):
print( 'compile error:' )
print( glGetShaderInfoLog(vs) )
glAttachShader(program, vs)
glAttachShader(program, fs)
glLinkProgram(program)
if not glGetProgramiv(program, GL_LINK_STATUS):
print( 'link error:' )
print( glGetProgramInfoLog(program) )
glGenVertexArrays(1, vao)
glBindVertexArray(vao)
def display(self):
global texture
global program
currentTime = time.time()
green = [ 0.0, 0.25, 0.0, 1.0 ]
glClearBufferfv(GL_COLOR, 0, green)
glActiveTexture(GL_TEXTURE0)
glBindTexture(GL_TEXTURE_2D, texture)
glUseProgram(program)
glViewport(0, 0, self.width, self.height)
glUniform1f(0, exposure)
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4)
overlay.clear()
buffer = ("Exposure = %2.2f (Numpad +/- to change)" % exposure)
overlay.drawText(buffer, 0, 0)
overlay.draw()
checkGLError()
glutSwapBuffers()
def reshape(self, width, height):
self.width = width
self.height = height
def keyboard(self, key, x, y ):
global fullscreen
global exposure
print ('key:' , key)
if key == b'\x1b': # ESC
sys.exit()
elif key == b'f' or key == b'F': #fullscreen toggle
if (fullscreen == True):
glutReshapeWindow(512, 512)
glutPositionWindow(int((1360/2)-(512/2)), int((768/2)-(512/2)))
fullscreen = False
else:
glutFullScreen()
fullscreen = True
elif key == b'+':
exposure *= 1.1
elif key == b'-':
exposure /= 1.1
def init(self):
pass
def timer(self, blah):
glutPostRedisplay()
glutTimerFunc( int(1/60), self.timer, 0)
time.sleep(1/60.0)
if __name__ == '__main__':
glutInit()
glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH)
glutInitWindowSize(512, 512)
w1 = glutCreateWindow('OpenGL SuperBible - HDR Exposure')
glutInitWindowPosition(int((1360/2)-(512/2)), int((768/2)-(512/2)))
fullscreen = False
#glutFullScreen()
scene = Scene(512,512)
glutReshapeFunc(scene.reshape)
glutDisplayFunc(scene.display)
glutKeyboardFunc(scene.keyboard)
glutIdleFunc(scene.display)
#glutTimerFunc( int(1/60), scene.timer, 0)
scene.init()
glutMainLoop()
Current output:
I was getting before updating the fragment shader:
Any help is appreciated. Thank You.
The result of exp(0.0) is 1.0, so the result of 1.0-exp(0.0) is 0.0.
You've to ensure that the value of the uniform exposure is not 0.0, to get a result greater than 0.0 for the expression:
c.xyz = vec3(1.0) - exp(-c.xyz * exposure);
The texture data is of type float. Create numpy.array with the element type numpy.float32, from the byte array, before initializing the texture image:
for i in range(0, h.miplevels):
if h.gltype == GL_FLOAT:
float_data = np.frombuffer(data[ptr:], dtype=np.float32)
glTexSubImage2D(GL_TEXTURE_2D, i, 0, 0, width, height, h.glformat, h.gltype, float_data)
else: # h.type == GL_UNSIGNED_BYTE
glTexSubImage2D(GL_TEXTURE_2D, i, 0, 0, width, height, h.glformat, h.gltype, data[ptr:])
ptr += height * calculate_stride(h, width, 1)
Note, you've to implement different cases for different types.
Related
I've been facing an issue for the past couple of days, and I still haven't been able to figure it out.. I'm trying to port a previous C++ Opengl project to PyOpengl, but I'm not able to get the object to render as it should. I'm simply trying to render a 3D grid model, which works in the original C++ code, but not in Python PyOpenGL.
What it should look like: (C++ OpenGL)
What it looks like (Python PyOpenGL)
This is the code I end up with in PyOpenGL :
import glfw
import glm
import numpy as np
from OpenGL.GL import *
import Shader
# Settings
SCR_WIDTH = 800
SCR_HEIGHT = 600
def framebuffer_size_callback(window, width, height):
if width != 0 and height != 0:
width = width
height = height
glViewport(0, 0, width, height)
def create_v_array():
vertexArray = []
indexArray = []
for x in range(-100, 102, 2):
# To draw lines across x axis from z = -1 to z = 1
vertexArray.append(glm.vec3(x / 100.0, 0.0, -1.0)) # Vertex position 1
vertexArray.append(glm.vec3(1.0, 1.0, 1.0)) # color for v1
vertexArray.append(glm.vec3(x / 100.0, 0.0, 1.0)) # Vertex position 2
vertexArray.append(glm.vec3(1.0, 1.0, 1.0)) # color for v2
for z in range(-100, 102, 2):
# To draw lines across z axis from x = -1 to x = 1
vertexArray.append(glm.vec3(-1.0, 0.0, z / 100.0)) # Vertex position 1
vertexArray.append(glm.vec3(1.0, 1.0, 1.0)) # color for v1
vertexArray.append(glm.vec3(1.0, 0.0, z / 100.0)) # Vertex position 2
vertexArray.append(glm.vec3(1.0, 1.0, 1.0)) # color for v2
for i in range(10000):
indexArray.append(i)
vao = GLuint()
vbo = GLuint()
ebo = GLuint()
vertexArray = np.array(vertexArray, dtype=np.float32)
indexArray = np.array(indexArray, dtype=np.float32)
# Bind vao
glGenVertexArrays(1, vao)
glBindVertexArray(vao)
# Upload Vertex Buffer (VBO) to the GPU, keep a reference to it (vertexBufferObject)
glGenBuffers(1, vbo)
glBindBuffer(GL_ARRAY_BUFFER, vbo)
glBufferData(GL_ARRAY_BUFFER, vertexArray.nbytes, vertexArray, GL_STATIC_DRAW)
# Upload Index Buffer (EBO) to the GPU, keep a reference to it (elementBufferObject)
glGenBuffers(1, ebo)
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo)
glBufferData(GL_ELEMENT_ARRAY_BUFFER, indexArray.nbytes, indexArray, GL_STATIC_DRAW)
# Position
glVertexAttribPointer(0,
3,
GL_FLOAT,
GL_FALSE,
24,
None
)
glEnableVertexAttribArray(0)
# Color
glVertexAttribPointer(1,
3,
GL_FLOAT,
GL_FALSE,
24,
ctypes.c_void_p(12)
)
glEnableVertexAttribArray(1)
glBindBuffer(GL_ARRAY_BUFFER, 0)
glBindVertexArray(0)
return vao
def main():
# Initialize the library
#glfw.glewExperimental = GL_TRUE
if not glfw.init():
return
glfw.window_hint(glfw.CONTEXT_VERSION_MAJOR, 3)
glfw.window_hint(glfw.CONTEXT_VERSION_MINOR, 2)
glfw.window_hint(glfw.OPENGL_PROFILE, glfw.OPENGL_CORE_PROFILE)
glfw.window_hint(glfw.OPENGL_FORWARD_COMPAT, GL_TRUE)
# Create a windowed mode window and its OpenGL context
window = glfw.create_window(SCR_WIDTH, SCR_HEIGHT, "OpenGL", None, None)
if not window:
glfw.terminate()
return
# Make the window's context current
glfw.make_context_current(window)
glfw.set_framebuffer_size_callback(window, framebuffer_size_callback)
#glEnable(GL_DEPTH_TEST)
#glDepthFunc(GL_LESS)
shader = Shader.Shader("VertexShader.vsh", "FragmentShader.fsh")
vao = create_v_array()
glUseProgram(shader.ID)
# Loop until the user closes the window
while not glfw.window_should_close(window):
glClearColor(0.2, 0.3, 0.3, 1.0)
glClear(GL_COLOR_BUFFER_BIT)
glUseProgram(shader.ID)
glBindVertexArray(vao)
model = glm.mat4(1)
view = glm.mat4(1)
model = glm.rotate(model, glm.radians(15.0), glm.vec3(1.0, 0.0, 0.0))
view = glm.translate(view, glm.vec3(0.0, 0.0, -1.0))
projection = glm.perspective(glm.radians(45.0), (SCR_WIDTH/SCR_HEIGHT), 0.1, 100.0)
shader.set_mat4("model", model)
shader.set_mat4("view", view)
shader.set_mat4("projection", projection)
glBindVertexArray(vao)
glDrawElements(GL_LINES, 20000, GL_UNSIGNED_INT, None)
glfw.swap_buffers(window)
glfw.poll_events()
glfw.terminate()
if __name__ == "__main__":
main()
Custom Shader class:
class Shader:
def __init__(self, vertex_path, fragment_path):
vertex_code = get_file_content(vertex_path)
fragment_code = get_file_content(fragment_path)
vertex = glCreateShader(GL_VERTEX_SHADER)
glShaderSource(vertex, vertex_code)
glCompileShader(vertex)
result = glGetShaderiv(vertex, GL_COMPILE_STATUS)
if not (result):
print("Vertex shader ERROR!")
raise RuntimeError(glGetShaderInfoLog(vertex))
fragment = glCreateShader(GL_FRAGMENT_SHADER)
glShaderSource(fragment, fragment_code)
glCompileShader(fragment)
result2 = glGetShaderiv(fragment, GL_COMPILE_STATUS)
if not (result2):
print("Fragment shader ERROR!")
raise RuntimeError(glGetShaderInfoLog(vertex))
self.ID = glCreateProgram()
glAttachShader(self.ID, vertex)
glAttachShader(self.ID, fragment)
glLinkProgram(self.ID)
success = glGetProgramiv(self.ID, GL_LINK_STATUS)
if not success:
print("gad darn")
infolog = glGetProgramInfoLog(self.ID)
print("ERROR::SHADER::PROGRAM::LINKING_FAILED\n", infolog)
glDeleteShader(vertex)
glDeleteShader(fragment)
def set_mat4(self, name, matrix):
glUniformMatrix4fv(glGetUniformLocation(self.ID, name), 1, GL_FALSE, glm.value_ptr(matrix))
def use(self):
glUseProgram(self.ID)
# Helper Function
def get_file_content(file):
with open(file) as f:
content = f.read()
return content
glsl files:
Vertex Shader:
#version 330 core
layout (location = 0) in vec3 aPos;
layout (location = 1) in vec3 aColor;
out vec3 vertexColor;
uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;
void main()
{
gl_Position = projection * view * model * vec4(aPos, 1.0);
vertexColor = aColor;
}
Fragment Shader:
#version 330 core
in vec3 vertexColor;
out vec4 FragColor;
void main()
{
FragColor = vec4(vertexColor.r, vertexColor.g, vertexColor.b, 1.0f);
}
The type of the indices must be integral instead of the floating point:
indexArray = np.array(indexArray, dtype=np.float32)
indexArray = np.array(indexArray, dtype=np.uint32)
I mostly ported over the dragon example from SB OpenGL. The output gif of the program is below the code.
My question what is what's the lookat function in python?
Supporting files: dragon.zip simply put pydragon.py into the folder 'dragon' and run
Source code of pydragon.py
#!/usr/bin/python3
import sys
import time
sys.path.append("./shared")
from sbmloader import SBMObject # location of sbm file format loader
from ktxloader import KTXObject # location of ktx file format loader
from sbmath import m3dDegToRad, m3dRadToDeg, m3dTranslateMatrix44, m3dRotationMatrix44, m3dMultiply, m3dOrtho, m3dPerspective, rotation_matrix, translate, m3dScaleMatrix44
fullscreen = True
import numpy.matlib
import numpy as np
import math
try:
from OpenGL.GLUT import *
from OpenGL.GL import *
from OpenGL.GLU import *
from OpenGL.raw.GL.ARB.vertex_array_object import glGenVertexArrays, glBindVertexArray
except:
print ('''
ERROR: PyOpenGL not installed properly.
''')
sys.exit()
identityMatrix = [1,0,0,0, 0,1,0,0, 0,0,1,0, 0,0,0,1]
clear_program = GLuint(0)
append_program = GLuint(0)
resolve_program = GLuint(0)
class textures:
color = GLuint(0)
normals = GLuint(0)
class uniforms_block:
mv_matrix = (GLfloat * 16)(*identityMatrix)
view_matrix = (GLfloat * 16)(*identityMatrix)
proj_matrix = (GLfloat * 16)(*identityMatrix)
uniforms_buffer = GLuint(0)
class uniforms:
mvp = GLuint(0)
fragment_buffer = GLuint(0)
head_pointer_image = GLuint(0)
atomic_counter_buffer = GLuint(0)
dummy_vao = GLuint(0)
uniform = uniforms()
myobject = SBMObject()
def length(v):
return math.sqrt(v[0]*v[0]+v[1]*v[1]+v[2]*v[2])
def normalize(v):
l = length(v)
#if (v[0] == 0 and v[1] == 0 and v[2] ==0):
# return [0.0, 1/3, 0.0]
return [v[0]/l, v[1]/l, v[2]/l]
def dot(v0, v1):
return v0[0]*v1[0]+v0[1]*v1[1]+v0[2]*v1[2]
def cross(v0, v1):
return [
v0[1]*v1[2]-v1[1]*v0[2],
v0[2]*v1[0]-v1[2]*v0[0],
v0[0]*v1[1]-v1[0]*v0[1]]
def m3dLookAt(eye, target, up):
mz = normalize( (eye[0]-target[0], eye[1]-target[1], eye[2]-target[2]) ) # inverse line of sight
mx = normalize( cross( up, mz ) )
my = normalize( cross( mz, mx ) )
tx = dot( mx, eye )
ty = dot( my, eye )
tz = -dot( mz, eye )
return np.array([mx[0], my[0], mz[0], 0, mx[1], my[1], mz[1], 0, mx[2], my[2], mz[2], 0, tx, ty, tz, 1])
def scale(s):
return [s,0,0,0, 0,s,0,0, 0,0,s,0, 0,0,0,1]
def link_from_shaders(shaders, shader_count, delete_shaders, check_errors=False):
program = GLuint(0)
program = glCreateProgram()
for i in range(0, shader_count):
glAttachShader(program, shaders[i]);
glLinkProgram(program);
if (delete_shaders):
for i in range(0, shader_count):
glDeleteShader(shaders[i]);
return program
def shader_load(filename, shader_type):
result = GLuint(0)
with open ( filename, "rb") as data:
result = glCreateShader(shader_type)
glShaderSource(result, data.read() )
glCompileShader(result)
return result
def load_shaders():
global clear_program
global append_program
global resolve_program
global uniform
shaders = [GLuint(0), GLuint(0)]
shaders[0] = shader_load("fragmentlist_shaders/clear.vs.glsl", GL_VERTEX_SHADER);
shaders[1] = shader_load("fragmentlist_shaders/clear.fs.glsl", GL_FRAGMENT_SHADER);
if (clear_program):
glDeleteProgram(clear_program);
clear_program = link_from_shaders(shaders, 2, True);
shaders[0] = shader_load("fragmentlist_shaders/append.vs.glsl", GL_VERTEX_SHADER);
shaders[1] = shader_load("fragmentlist_shaders/append.fs.glsl", GL_FRAGMENT_SHADER);
if (append_program):
glDeleteProgram(append_program);
append_program = link_from_shaders(shaders, 2, True);
uniform.mvp = glGetUniformLocation(append_program, "mvp");
shaders[0] = shader_load("fragmentlist_shaders/resolve.vs.glsl", GL_VERTEX_SHADER);
shaders[1] = shader_load("fragmentlist_shaders/resolve.fs.glsl", GL_FRAGMENT_SHADER);
if (resolve_program):
glDeleteProgram(resolve_program)
resolve_program = link_from_shaders(shaders, 2, True);
class Scene:
def __init__(self, width, height):
global uniforms_buffer
global fragment_buffer
global atomic_counter_buffer
global head_pointer_image
global dummy_vao
global myobject
self.width = width
self.height = height
load_shaders()
glGenBuffers(1, uniforms_buffer)
glBindBuffer(GL_UNIFORM_BUFFER, uniforms_buffer)
glBufferData(GL_UNIFORM_BUFFER, sizeof(GLfloat * 16 *3), None, GL_DYNAMIC_DRAW)
myobject.load("dragon.sbm")
glGenBuffers(1, fragment_buffer)
glBindBuffer(GL_SHADER_STORAGE_BUFFER, fragment_buffer);
glBufferData(GL_SHADER_STORAGE_BUFFER, 1024 * 1024 * 16, None, GL_DYNAMIC_COPY)
glGenBuffers(1, atomic_counter_buffer);
glBindBuffer(GL_ATOMIC_COUNTER_BUFFER, atomic_counter_buffer);
glBufferData(GL_ATOMIC_COUNTER_BUFFER, 4, None, GL_DYNAMIC_COPY);
head_pointer_image = glGenTextures(1)
glBindTexture(GL_TEXTURE_2D, head_pointer_image);
glTexStorage2D(GL_TEXTURE_2D, 1, GL_R32UI, 1024, 1024);
glGenVertexArrays(1, dummy_vao);
glBindVertexArray(dummy_vao);
def display(self):
green = [ 0.0, 0.1, 0.0, 0.0 ]
currentTime = time.time()
f = currentTime
zeros = [ 0.0, 0.0, 0.0, 0.0 ]
gray = [ 0.1, 0.1, 0.1, 0.0 ]
ones = [ 1.0 ]
glViewport(0, 0, self.width , self.height);
glMemoryBarrier(GL_SHADER_IMAGE_ACCESS_BARRIER_BIT | GL_ATOMIC_COUNTER_BARRIER_BIT | GL_SHADER_STORAGE_BARRIER_BIT);
glUseProgram(clear_program);
glBindVertexArray(dummy_vao);
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
glUseProgram(append_program)
model_matrix = (GLfloat * 16)(*identityMatrix)
model_matrix = scale(6.0)
view_matrix = (GLfloat * 16)(*identityMatrix)
view_matrix = m3dLookAt([math.cos(f * 0.35) * 120.0, math.cos(f * 0.4) * 30.0, math.sin(f * 0.35) * 120.0],
[0.0, -20.0, 0.0],
[0.0, 1, 0.0])
mv_matrix = (GLfloat * 16)(*identityMatrix)
mv_matrix = m3dMultiply(view_matrix , model_matrix)
proj_matrix = (GLfloat * 16)(*identityMatrix)
proj_matrix = m3dPerspective(m3dDegToRad(50.0), float(self.width) / float(self.height), 0.1, 1000.0)
glUniformMatrix4fv(uniform.mvp, 1, GL_FALSE, m3dMultiply(proj_matrix , mv_matrix))
zero = 0;
glBindBufferBase(GL_ATOMIC_COUNTER_BUFFER, 0, atomic_counter_buffer)
# next line not working ????
#glBufferSubData(GL_ATOMIC_COUNTER_BUFFER, 0, sys.getsizeof(zero), zero);
glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 0, fragment_buffer)
glBindImageTexture(0, head_pointer_image, 0, GL_FALSE, 0, GL_READ_WRITE, GL_R32UI)
glMemoryBarrier(GL_SHADER_IMAGE_ACCESS_BARRIER_BIT | GL_ATOMIC_COUNTER_BARRIER_BIT | GL_SHADER_STORAGE_BARRIER_BIT)
myobject.render()
glMemoryBarrier(GL_SHADER_IMAGE_ACCESS_BARRIER_BIT | GL_ATOMIC_COUNTER_BARRIER_BIT | GL_SHADER_STORAGE_BARRIER_BIT)
glUseProgram(resolve_program)
glBindVertexArray(dummy_vao)
glMemoryBarrier(GL_SHADER_IMAGE_ACCESS_BARRIER_BIT | GL_ATOMIC_COUNTER_BARRIER_BIT | GL_SHADER_STORAGE_BARRIER_BIT)
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4)
glutSwapBuffers()
def reshape(self, width, height):
self.width = width
self.height = height
def keyboard(self, key, x, y ):
global fullscreen
print ('key:' , key)
if key == b'\x1b': # ESC
sys.exit()
elif key == b'f' or key == b'F': #fullscreen toggle
if (fullscreen == True):
glutReshapeWindow(512, 512)
glutPositionWindow(int((1360/2)-(512/2)), int((768/2)-(512/2)))
fullscreen = False
else:
glutFullScreen()
fullscreen = True
print('done')
def init(self):
pass
def timer(self, blah):
glutPostRedisplay()
glutTimerFunc( int(1/60), self.timer, 0)
time.sleep(1/60.0)
if __name__ == '__main__':
start = time.time()
glutInit()
glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH)
glutInitWindowSize(512, 512)
w1 = glutCreateWindow('OpenGL SuperBible - Fragment List')
glutInitWindowPosition(int((1360/2)-(512/2)), int((768/2)-(512/2)))
fullscreen = False
many_cubes = False
#glutFullScreen()
scene = Scene(512,512)
glutReshapeFunc(scene.reshape)
glutDisplayFunc(scene.display)
glutKeyboardFunc(scene.keyboard)
glutIdleFunc(scene.display)
#glutTimerFunc( int(1/60), scene.timer, 0)
scene.init()
glutMainLoop()
The output is supposed to appear like the following:
Ported from fragmentlist.cpp found there from the Superbible OpenGL 7th ed.
Current Question:
Any ideas why the texture rendered on the dragon is not translucent as the expected output has it?
The view space is the local system which is defined by the point of view onto the scene.
The position of the view, the line of sight and the upwards direction of the view, define a coordinate system relative to the world coordinate system. The objects of a scene have to be drawn in relation to the view coordinate system, to be "seen" from the viewing position. The inverse matrix of the view coordinate system is named the view matrix. This matrix transforms from world coordinates to view coordinates.
The code below defines a matrix that exactly encapsulates the steps necessary to calculate a look at the scene:
Converting model coordinates into view system coordinates.
Rotation, to look in the direction of the view.
Movement to the eye position.
Euclidean length of a vector:
def length(v):
return math.sqrt(v[0]*v[0]+v[1]*v[1]+v[2]*v[2])
Unit vector:
def normalize(v):
l = length(v)
return [v[0]/l, v[1]/l, v[2]/l]
Dot product:
def dot(v0, v1):
return v0[0]*v1[0]+v0[1]*v1[1]+v0[2]*v1[2]
Cross product:
def cross(v0, v1):
return [
v0[1]*v1[2]-v1[1]*v0[2],
v0[2]*v1[0]-v1[2]*v0[0],
v0[0]*v1[1]-v1[0]*v0[1]]
The following code does the same as gluLookAt or glm::lookAt does:
The parameter eye is the point of view, target is the point which is looked at and up is the upwards direction.
def m3dLookAt(eye, target, up):
mz = normalize( (eye[0]-target[0], eye[1]-target[1], eye[2]-target[2]) ) # inverse line of sight
mx = normalize( cross( up, mz ) )
my = normalize( cross( mz, mx ) )
tx = dot( mx, eye )
ty = dot( my, eye )
tz = -dot( mz, eye )
return np.array([mx[0], my[0], mz[0], 0, mx[1], my[1], mz[1], 0, mx[2], my[2], mz[2], 0, tx, ty, tz, 1])
Use it like this:
view_matrix = m3dLookAt([0, 0, 20], [0, 0, 0], [0, 1, 0])
The source is of a green dragon rendering. My question is how to get the clip distances working on it? Also, the textures are not appearing as the expected output. Any ideas what can be modified in the source code to render the program as expected?
Update: With the excellent help and superb answers of Rabbid76 the clip distance is working and texture loading is working! Thank You.
Bonus example: clipdistance_torus_package.zip a clip distance example with a torus and textures!
Expected output:
Files to run: clipdistance_dragon.zip
#!/usr/bin/python3
import sys
import time
import ctypes
fullscreen = True
sys.path.append("./shared")
from sbmloader import SBMObject # location of sbm file format loader
from ktxloader import KTXObject
from sbmath import m3dDegToRad, m3dRadToDeg, m3dTranslateMatrix44, m3dRotationMatrix44, m3dMultiply, m3dOrtho, m3dPerspective, rotation_matrix, translate, m3dScaleMatrix44, \
scale, m3dLookAt, normalize
try:
from OpenGL.GLUT import *
from OpenGL.GL import *
from OpenGL.GLU import *
from OpenGL.raw.GL.ARB.vertex_array_object import glGenVertexArrays, glBindVertexArray
except:
print ('''
ERROR: PyOpenGL not installed properly.
''')
sys.exit()
import numpy as np
from math import cos, sin
identityMatrix = [1,0,0,0, 0,1,0,0, 0,0,1,0, 0,0,0,1]
myobject = SBMObject()
render_program = GLuint(0)
paused = False
class uniforms:
proj_matrix = GLint(0)
mv_matrix = GLint(0)
clip_plane = GLint(0)
clip_sphere = GLint(0)
uniform = uniforms()
def shader_load(filename, shader_type):
result = GLuint(0)
with open ( filename, "rb") as data:
result = glCreateShader(shader_type)
glShaderSource(result, data.read() )
glCompileShader(result)
if not glGetShaderiv(result, GL_COMPILE_STATUS):
print( 'compile error:' )
print( glGetShaderInfoLog(result) )
return result
def link_from_shaders(shaders, shader_count, delete_shaders, check_errors=False):
program = GLuint(0)
program = glCreateProgram()
for i in range(0, shader_count):
glAttachShader(program, shaders[i])
glLinkProgram(program)
if not glGetProgramiv(program, GL_LINK_STATUS):
print( 'link error:' )
print( glGetProgramInfoLog(program) )
if (delete_shaders):
for i in range(0, shader_count):
glDeleteShader(shaders[i])
return program
def load_shaders():
global render_program
global uniform
if (render_program):
glDeleteProgram(render_program);
shaders = [
shader_load("render.vs.glsl", GL_VERTEX_SHADER),
shader_load("render.fs.glsl", GL_FRAGMENT_SHADER)
]
render_program = link_from_shaders(shaders, 2, True)
uniform.proj_matrix = glGetUniformLocation(render_program, "proj_matrix");
uniform.mv_matrix = glGetUniformLocation(render_program, "mv_matrix");
uniform.clip_plane = glGetUniformLocation(render_program, "clip_plane");
uniform.clip_sphere = glGetUniformLocation(render_program, "clip_sphere");
tex_dragon=None
class Scene:
def __init__(self, width, height):
global myobject, tex_dragon
myobject.load("dragon.sbm");
load_shaders()
ktxobj = KTXObject()
tex_dragon = ktxobj.ktx_load("pattern1.ktx")
def display(self):
global paused
currentTime = time.time()
black = [ 0.0, 0.0, 0.0, 0.0 ]
one = 1.0
last_time = 0.0
total_time = 0.0
if (not paused):
total_time += (currentTime - last_time)
last_time = currentTime
f = total_time
glClearBufferfv(GL_COLOR, 0, black)
glClearBufferfv(GL_DEPTH, 0, one)
glUseProgram(render_program)
proj_matrix = (GLfloat * 16)(*identityMatrix)
proj_matrix = m3dPerspective(m3dDegToRad(50.0), float(self.width) / float(self.height), 0.1, 1000.0)
T1 = (GLfloat * 16)(*identityMatrix)
m3dTranslateMatrix44(T1, 0.0, 0.0, -15.0)
RY = (GLfloat * 16)(*identityMatrix)
m3dRotationMatrix44(RY, f * 0.34, 0.0, 1.0, 0.0)
T2 = (GLfloat * 16)(*identityMatrix)
m3dTranslateMatrix44(T2, 0.0, -4.0, 0.0)
mv_matrix = (GLfloat * 16)(*identityMatrix)
mv_matrix = m3dMultiply(T1, m3dMultiply(RY, T2))
RX = (GLfloat * 16)(*identityMatrix)
m3dRotationMatrix44(RX, f * 6.0, 1.0, 0.0, 0.0)
RY = (GLfloat * 16)(*identityMatrix)
m3dRotationMatrix44(RY, f * 7.3, 0.0, 1.0, 0.0)
plane_matrix = (GLfloat * 16)(*identityMatrix)
plane_matrix = m3dMultiply(RX , RY )
plane = plane_matrix[0:4]
plane[3] = 0
plane = normalize(plane)
clip_sphere = [sin(f * 0.7) * 3.0, cos(f * 1.9) * 3.0, sin(f * 0.1) * 3.0, cos(f * 1.7) + 2.5]
glUniformMatrix4fv(uniform.proj_matrix, 1, GL_FALSE, proj_matrix)
glUniformMatrix4fv(uniform.mv_matrix, 1, GL_FALSE, mv_matrix)
glUniform4fv(uniform.clip_plane, 1, plane)
glUniform4fv(uniform.clip_sphere, 1, clip_sphere)
glEnable(GL_DEPTH_TEST)
glEnable(GL_CLIP_DISTANCE0)
glEnable(GL_CLIP_DISTANCE1)
glActiveTexture(GL_TEXTURE0)
glBindTexture(GL_TEXTURE_2D, tex_dragon)
myobject.render()
glutSwapBuffers()
def reshape(self, width, height):
self.width = width
self.height = height
def keyboard(self, key, x, y ):
global fullscreen
global paused
print ('key:' , key)
if key == b'\x1b': # ESC
sys.exit()
elif key == b'f' or key == b'F': #fullscreen toggle
if (fullscreen == True):
glutReshapeWindow(512, 512)
glutPositionWindow(int((1360/2)-(512/2)), int((768/2)-(512/2)))
fullscreen = False
else:
glutFullScreen()
fullscreen = True
elif key == b'p' or key == b'P':
paused = not paused
elif key == b'r' or key == b'R':
pass
print('done')
def init(self):
pass
def timer(self, blah):
glutPostRedisplay()
glutTimerFunc( int(1/60), self.timer, 0)
time.sleep(1/60.0)
if __name__ == '__main__':
start = time.time()
glutInit()
glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH)
glutInitWindowSize(512, 512)
w1 = glutCreateWindow('OpenGL SuperBible - Clip Distance')
glutInitWindowPosition(int((1360/2)-(512/2)), int((768/2)-(512/2)))
fullscreen = False
#glutFullScreen()
scene = Scene(512,512)
glutReshapeFunc(scene.reshape)
glutDisplayFunc(scene.display)
glutKeyboardFunc(scene.keyboard)
glutIdleFunc(scene.display)
#glutTimerFunc( int(1/60), scene.timer, 0)
scene.init()
glutMainLoop()
ported into python from clipdistance.cpp , source of sbmobject.cpp just in case sbmloader.py is in question for the texture issue.
The C++ code from the example
vmath::mat4 plane_matrix = vmath::rotate(f * 6.0f, 1.0f, 0.0f, 0.0f) *
vmath::rotate(f * 7.3f, 0.0f, 1.0f, 0.0f);
corresponds to the following python code
RX = (GLfloat * 16)(*identityMatrix)
m3dRotationMatrix44(RX, f * 6.0, 1.0, 0.0, 0.0)
RY = (GLfloat * 16)(*identityMatrix)
m3dRotationMatrix44(RY, f * 7.3, 0.0, 1.0, 0.0)
plane_matrix = (GLfloat * 16)(*identityMatrix)
plane_matrix = m3dMultiply(RX , RY)
Note, you've to swap RX and RY in the matrix multiplication.
Your functions length and normalize can only deal with vectors which have 3 components (x, y, z). In compare the C++ function vmath::normalize from the example can handle vectors with 4 components (x, y, z, w), too.
Further the "division by zero" handling is missing in normalize.
Adapt the functions normalize and length, to deal with any vector size.
If the length of a vector is 0, then all its components are 0. There is no correct solution for that, so just return a copy of the vector itself.
def length(v):
sum_sq = sum([s*s for s in v])
return math.sqrt(sum_sq)
def normalize(v):
l = length(v)
if l == 0.0:
return v[:]
return [s/l for s in v]
Now you can port the C++ code from the example
vmath::vec4 plane = plane_matrix[0];
plane[3] = 0.0f;
plane = vmath::normalize(plane);
very straight to python:
plane = plane_matrix[0:4]
plane[3] = 0
plane = normalize(plane)
Further, there is an issue in the sbmloader module.
Only the array of vertex coordinates and texture coordinates is specified. The normal vectors are skipped.
Just skip the line
if attrib.name=='position' or attrib.name=='map1':
to fix the issue:
for attrib_i, attrib in enumerate(vertex_attrib_chunk.attrib_data):
#if attrib.name=='position' or attrib.name=='map1':
glVertexAttribPointer(attrib_i,
attrib.size, attrib.type,
GL_TRUE if (attrib.flags & SB6M_VERTEX_ATTRIB_FLAG_NORMALIZED) != 0 else GL_FALSE,
attrib.stride, ctypes.c_void_p(int(attrib.data_offset)))
glEnableVertexAttribArray(attrib_i)
If you additionally want to wrap a texture to the model, then you've to add the texture coordinate attribute to the vertex shader:
layout (location = 2) in vec2 tc;
And to pass it by an output to the next shader stage
out VS_OUT
{
vec3 N;
vec3 L;
vec3 V;
vec2 T;
} vs_out;
void main()
{
// ...
vs_out.T = tc;
// ...
}
In the fragment shader you've to add the texture sampler uniform
layout (binding = 0) uniform sampler2D tex;
Read the color form the texture
vec4 texColor = texture(tex, fs_in.T);
Multiply the output color by the texture color
color = vec4(diffuse + specular + rim, 1.0) * texColor;
Fragment shader (note, I changed diffuse_albedo):
#version 420 core
// Output
layout (location = 0) out vec4 color;
// Input from vertex shader
in VS_OUT
{
vec3 N;
vec3 L;
vec3 V;
vec2 T;
} fs_in;
// Material properties
uniform vec3 diffuse_albedo = vec3(0.5);
uniform vec3 specular_albedo = vec3(0.7);
uniform float specular_power = 128.0;
uniform vec3 rim_color = vec3(0.1, 0.2, 0.2);
uniform float rim_power = 5.0;
layout (binding = 0) uniform sampler2D tex;
vec3 calculate_rim(vec3 N, vec3 V)
{
float f = 1.0 - dot(N, V);
f = smoothstep(0.0, 1.0, f);
f = pow(f, rim_power);
return f * rim_color;
}
void main(void)
{
// Normalize the incoming N, L and V vectors
vec3 N = normalize(fs_in.N);
vec3 L = normalize(fs_in.L);
vec3 V = normalize(fs_in.V);
// Calculate R locally
vec3 R = reflect(-L, N);
// Compute the diffuse and specular components for each fragment
vec3 diffuse = max(dot(N, L), 0.0) * diffuse_albedo;
vec3 specular = pow(max(dot(R, V), 0.0), specular_power) * specular_albedo;
vec3 rim = calculate_rim(N, V);
// read color from the texture
vec4 texColor = texture(tex, fs_in.T);
// Write final color to the framebuffer
color = vec4(diffuse + specular + rim, 1.0) * texColor;
}
I recommend to add shader compile and link error logging:
glCompileShader(result)
if not glGetShaderiv(result, GL_COMPILE_STATUS):
print( 'compile error:' )
print( glGetShaderInfoLog(result) )
glLinkProgram(program)
if not glGetProgramiv(program, GL_LINK_STATUS):
print( 'link error:' )
print( glGetProgramInfoLog(program) )
Read a texture at the initialization of the application
class Scene:
def __init__(self, width, height):
global myobject, tex_dragon
myobject.load("dragon.sbm")
load_shaders()
ktxobj = KTXObject()
tex_dragon = ktxobj.ktx_load("texture_file_name.ktx")
Bind the texture before drawing the model
glActiveTexture(GL_TEXTURE0)
glBindTexture(GL_TEXTURE_2D, tex_dragon)
myobject.render()
I'm trying to create a program with modern OpenGL code that displays a QUAD with a texture mapped onto it.
The texture should be stretched to match the quad size. Right now the texture repeats.
I've seen code that maps the texture to the quad if the each vertex and mapping is done individually in the code. However, I think now we are supposed to use vertex shaders? With OpenGL 4.5 or whatever, how is this supposed to be done?
"""
Open a window that displays a quad with an image on it.
"""
from OpenGL.GL import *
from OpenGL.GLU import *
from OpenGL.GLUT import *
from PIL import Image
from math import *
from time import *
class MyApplication:
""" Main application class. """
def __init__(self):
self.vao = 0
def load_texture(self, file_name):
image = Image.open(file_name)
width = image.size[0]
height = image.size[1]
image_bytes = image.convert("RGBA").tobytes ( "raw", "RGBA", 0, -1)
texture = glGenTextures(1)
glBindTexture ( GL_TEXTURE_2D, texture )
glTexParameterf ( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT )
glTexParameterf ( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT )
glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,GL_LINEAR )
glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,GL_LINEAR_MIPMAP_LINEAR )
gluBuild2DMipmaps ( GL_TEXTURE_2D, GL_RGBA, width, height, GL_RGBA, GL_UNSIGNED_BYTE, image_bytes )
return texture
def compile_shaders(self):
""" Get the shaders ready. """
# Create a triangle with three (x, y, z, ?) points.
vertex_shader_source = """
#version 450 core
void main( void)
{
// Declare a hard-coded array of positions
const vec4 vertices[4] = vec4[4](vec4(-0.5, 0.5, 0.5, 1.0),
vec4( 0.5, 0.5, 0.5, 1.0),
vec4( 0.5, -0.5, 0.5, 1.0),
vec4(-0.5, -0.5, 0.5, 1.0));
// Index into our array using gl_VertexID
gl_Position = vertices[gl_VertexID];
}
"""
vertex_shader = glCreateShader(GL_VERTEX_SHADER)
glShaderSource(vertex_shader, vertex_shader_source)
glCompileShader(vertex_shader)
# Specify the color of our fragment (RGBA)
texture = self.load_texture("test_ship.png")
fragment_shader_source = """
#version 450 core
uniform sampler2D s;
out vec4 color;
void main(void)
{
color = texture(s, gl_FragCoord.xy / textureSize(s, 0));
}
"""
fragment_shader = glCreateShader(GL_FRAGMENT_SHADER)
glShaderSource(fragment_shader, fragment_shader_source)
glCompileShader(fragment_shader)
# --- Create a program
program = glCreateProgram()
glAttachShader(program, vertex_shader)
glAttachShader(program, fragment_shader)
glLinkProgram(program)
glGenVertexArrays(1, self.vao)
glBindVertexArray(self.vao)
# --- Clean up now that we don't need these shaders anymore.
glDeleteShader(vertex_shader)
glDeleteShader(fragment_shader)
return program
def startup(self):
self.rendering_program = self.compile_shaders()
self.vertex_array_object = GLuint()
glCreateVertexArrays(1, self.vertex_array_object)
def render(self):
# Support transparency
glEnable(GL_BLEND)
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)
# Get a color based on the time
color = (sin(time()), cos(time()), 0)
# Clear the screen
glClearBufferfv(GL_COLOR, 0, color)
# Tell the computer what to render
glUseProgram(self.rendering_program)
glDrawArrays(GL_QUADS, 0, 4)
# Display
glutSwapBuffers()
def animate(self):
glutPostRedisplay()
def run(self):
glutInit(sys.argv)
glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH)
glutInitWindowSize(500, 500)
glutInitWindowPosition(0, 0)
glutCreateWindow(b"Simple PyOpenGL example")
self.startup()
glutIdleFunc(self.animate)
glutDisplayFunc(self.render)
glutMainLoop()
my_application = MyApplication()
my_application.run()
I believe there are two problems here:
1) If you see a repeating pattern, given your current WRAP_S and WRAP_T settings, you can assume that your UV coordinates are wrong.
In your fragment shader, you get the UV coordinate using the following calculation:
color = texture(s, gl_FragCoord.xy / textureSize(s, 0));
However, looking at your quad coordinates, this is not going to map to a [0,1] interval, as required for texture coordinates. (if it goes below or beyond this interval, you will get a modulo of the value).
2) If you don't want it to repeat, use the following:
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE)
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE)
I am trying to get shadow mapping working using GLSL. Unfortunately my depth render results are unusable even I have a pretty decent depth buffer precision. It is rendering like wireframe, following image may be a better description.
I am also including a test case(single file including shader), only dependency is pyopengl.
# shadow mapping test
# utkualtinkaya at gmail
# shader is from http://www.fabiensanglard.net/shadowmapping/index.php
from OpenGL.GL import *
from OpenGL.GLU import *
from OpenGL.GLUT import *
from OpenGL.GL.shaders import *
from OpenGL.GL.framebufferobjects import *
import math
class Camera:
def __init__(self):
self.rotx, self.roty = math.pi/4, math.pi/4
self.distance = 100
self.moving = False
self.ex, self.ey = 0, 0
self.size = (800, 600)
def load_matrices(self):
glViewport(0, 0, *self.size)
y = math.cos(self.roty) * self.distance
x = math.sin(self.roty) * math.cos(self.rotx) * self.distance
z = math.sin(self.roty) * math.sin(self.rotx) * self.distance
glMatrixMode(GL_PROJECTION)
glLoadIdentity()
gluPerspective(45.0, self.size[0]/float(self.size[1]), 1, 1000)
glMatrixMode(GL_MODELVIEW)
glLoadIdentity()
gluLookAt(x,y,z, 0,0,0, 0,1,0)
def on_mouse_button (self, b, s, x, y):
self.moving = not s
self.ex, self.ey = x, y
if b in [3, 4]:
dz = (1 if b == 3 else -1)
self.distance += self.distance/15.0 * dz;
def on_mouse_move(self, x, y, z = 0):
if self.moving:
self.rotx += (x-self.ex) / 300.0
self.roty += -(y-self.ey) / 300.0
self.ex, self.ey = x, y
def set_size(self, w, h):
self.size = w, h
class Shader():
def __init__(self):
self.is_built = False
self.uniforms = {}
def build(self):
self.program = compileProgram(
compileShader('''
uniform mat4 camMatrix;
uniform mat4 shadowMatrix;
varying vec4 depthProjection;
uniform bool useShadow;
void main() {
gl_Position = camMatrix * gl_ModelViewMatrix * gl_Vertex;
depthProjection = shadowMatrix * gl_ModelViewMatrix * gl_Vertex;
gl_FrontColor = gl_Color;
}
''',GL_VERTEX_SHADER),
compileShader('''
varying vec4 depthProjection;
uniform sampler2D shadowMap;
uniform bool useShadow;
void main () {
float shadow = 1.0;
if (useShadow) {
vec4 shadowCoord = depthProjection / depthProjection.w ;
// shadowCoord.z -= 0.0003;
float distanceFromLight = texture2D(shadowMap, shadowCoord.st).z;
if (depthProjection .w > 0.0)
shadow = distanceFromLight < shadowCoord.z ? 0.5 : 1.0 ;
}
gl_FragColor = shadow * gl_Color;
}
''',GL_FRAGMENT_SHADER),)
self.is_built = True
self.uniforms['camMatrix'] = glGetUniformLocation(self.program, 'camMatrix')
self.uniforms['shadowMatrix'] = glGetUniformLocation(self.program, 'shadowMatrix')
self.uniforms['shadowMap'] = glGetUniformLocation(self.program, 'shadowMap')
self.uniforms['useShadow'] = glGetUniformLocation(self.program, 'useShadow')
print self.uniforms
def use(self):
if not self.is_built:
self.build()
glUseProgram(self.program)
class Test:
def __init__(self):
glutInit(sys.argv)
glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_ALPHA | GLUT_DEPTH)
glutInitWindowSize(800, 600)
glutInitWindowPosition(1120/2, 100)
self.window = glutCreateWindow("Shadow Test")
self.cam = Camera()
self.light = Camera()
self.cam.set_size(800, 600)
self.light.set_size(2048, 2048)
self.light.distance = 100
self.shader = Shader()
self.initialized = False
def setup(self):
self.initialized = True
glClearColor(0,0,0,1.0);
glDepthFunc(GL_LESS)
glEnable(GL_DEPTH_TEST)
self.fbo = glGenFramebuffers(1);
self.shadowTexture = glGenTextures(1)
glBindFramebuffer(GL_FRAMEBUFFER, self.fbo)
w, h = self.light.size
glActiveTexture(GL_TEXTURE5)
glBindTexture(GL_TEXTURE_2D, self.shadowTexture)
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP );
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP );
glTexImage2D( GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, w, h, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, None)
glDrawBuffer(GL_NONE)
glReadBuffer(GL_NONE)
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, self.fbo, 0)
FBOstatus = glCheckFramebufferStatus(GL_FRAMEBUFFER)
if FBOstatus != GL_FRAMEBUFFER_COMPLETE:
print ("GL_FRAMEBUFFER_COMPLETE_EXT failed, CANNOT use FBO\n");
glBindFramebuffer(GL_FRAMEBUFFER, 0)
#glActiveTexture(GL_TEXTURE0)
def draw(self):
glPushMatrix()
glTranslate(0, 10 ,0)
glColor4f(0, 1, 1, 1)
glutSolidCube(5)
glPopMatrix()
glPushMatrix()
glColor4f(0.5, 0.5, .5, 1)
glScale(100, 1, 100)
glutSolidCube(1)
glPopMatrix()
def apply_camera(self, cam):
cam.load_matrices()
model_view = glGetDoublev(GL_MODELVIEW_MATRIX);
projection = glGetDoublev(GL_PROJECTION_MATRIX);
glMatrixMode(GL_MODELVIEW)
glLoadIdentity()
glMultMatrixd(projection)
glMultMatrixd(model_view)
glUniformMatrix4fv(self.shader.uniforms['camMatrix'], 1, False, glGetFloatv(GL_MODELVIEW_MATRIX))
glLoadIdentity()
def shadow_pass(self):
glUniform1i(self.shader.uniforms['useShadow'], 0)
glBindFramebuffer(GL_FRAMEBUFFER, self.fbo)
glClear(GL_DEPTH_BUFFER_BIT)
glCullFace(GL_FRONT)
self.apply_camera(self.light)
self.draw()
glBindFramebuffer(GL_FRAMEBUFFER, 0)
def final_pass(self):
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
self.light.load_matrices()
model_view = glGetDoublev(GL_MODELVIEW_MATRIX);
projection = glGetDoublev(GL_PROJECTION_MATRIX);
glMatrixMode(GL_MODELVIEW)
glLoadIdentity()
bias = [ 0.5, 0.0, 0.0, 0.0,
0.0, 0.5, 0.0, 0.0,
0.0, 0.0, 0.5, 0.0,
0.5, 0.5, 0.5, 1.0]
glLoadMatrixd(bias)
glMultMatrixd(projection)
glMultMatrixd(model_view)
glUniformMatrix4fv(self.shader.uniforms['shadowMatrix'], 1, False, glGetFloatv(GL_MODELVIEW_MATRIX))
glActiveTexture(GL_TEXTURE5)
glBindTexture(GL_TEXTURE_2D, self.shadowTexture)
glUniform1i(self.shader.uniforms['shadowMap'], 5)
glUniform1i(self.shader.uniforms['useShadow'], 1);
self.apply_camera(self.cam)
glLoadIdentity()
glCullFace(GL_BACK)
self.draw()
def render(self):
if not self.initialized: self.setup()
self.shader.use()
self.shadow_pass()
self.final_pass()
glutSwapBuffers()
def mouse_move(self, *args):
self.cam.on_mouse_move(*args)
self.light.on_mouse_move(*args)
def mouse_button(self, b, *args):
if b==0:
self.light.on_mouse_button(b, *args)
else:
self.cam.on_mouse_button(b, *args)
def main(self):
glutDisplayFunc(self.render)
glutIdleFunc(self.render)
glutMouseFunc(self.mouse_button)
glutMotionFunc(self.mouse_move)
glutReshapeFunc(self.cam.set_size)
#self.setup()
glutMainLoop()
if __name__ == '__main__':
test = Test()
test.main()
solved it, it is the binding issue, in shadow pass fragment shader I simply checked a boolean value to disable reading the texture, but that was not enough. I should have unbind the texture before shadow pass, that is mentioned in documentation as:
Quote from OpenGL Refence:
Special precautions need to be taken to avoid attaching a texture image to the currently bound framebuffer while the texture object is currently bound and potentially sampled by the current vertex or fragment shader.
NVIDIA ignores this, ATI behaves pretty much "undefined" as the documentation says.
// shadowCoord.z -= 0.0003;
Your commented out shadow bias is the solution to your z-fighting problem. Change it to some value e.g. += 0.0005 and you should be good to go.