global window

# Initialize the library

if not glfw.init():

print("Failed to initialize GLFW\n",file=sys.stderr)

return False

# Open Window and create its OpenGL context

window = glfw.create_window(1024, 768, "Tutorial 05", None, None) #(in the accompanying source code this variable will be global)

glfw.window_hint(glfw.SAMPLES, 4)

glfw.window_hint(glfw.CONTEXT_VERSION_MAJOR, 3)

glfw.window_hint(glfw.CONTEXT_VERSION_MINOR, 3)

glfw.window_hint(glfw.OPENGL_FORWARD_COMPAT, GL_TRUE)

glfw.window_hint(glfw.OPENGL_PROFILE, glfw.OPENGL_CORE_PROFILE)

if not window:

print("Failed to open GLFW window. If you have an Intel GPU, they are not 3.3 compatible. Try the 2.1 version of the tutorials.\n",file=sys.stderr)

glfw.terminate()

return False

# Initialize GLEW

glfw.make_context_current(window)

glewExperimental = True

# GLEW is a framework for testing extension availability. Please see tutorial notes for

# more information including why can remove this code.

if glewInit() != GLEW_OK:

print("Failed to initialize GLEW\n",file=sys.stderr);

return False

""" Bind texture_id using several different modes

Notes:

Without mipmapping the texture is incomplete

and requires additional constraints on OpenGL

to properly render said texture.

Use 'MIN_FILTER" or 'MAX_LEVEL' to render

a generic texture with a single resolution

Ref:

[] - http://www.opengl.org/wiki/Common_Mistakes#Creating_a_complete_texture

[] - http://gregs-blog.com/2008/01/17/opengl-texture-filter-parameters-explained/

TODO:

- Rename modes to something useful

"""

if mode == 'DEFAULT':

glBindTexture(GL_TEXTURE_2D, texture_id)

glPixelStorei(GL_UNPACK_ALIGNMENT,1)

elif mode == 'MIN_FILTER':

glBindTexture(GL_TEXTURE_2D, texture_id)

glPixelStorei(GL_UNPACK_ALIGNMENT,1)

glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP)

glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP)

glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR)

glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR)

elif mode == 'MAX_LEVEL':

glBindTexture(GL_TEXTURE_2D, texture_id)

glPixelStorei(GL_UNPACK_ALIGNMENT,1)

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 0)

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 0)

else:

glBindTexture(GL_TEXTURE_2D, texture_id)

glPixelStorei(GL_UNPACK_ALIGNMENT,1)

# Generate mipmaps? Doesn't seem to work

im = pil_open(file_name)

try:

width,height,image = im.size[0], im.size[1], im.tostring("raw", "RGBA", 0, -1)

except SystemError:

width,height,image = im.size[0], im.size[1], im.tostring("raw", "RGBX", 0, -1)

texture_id = glGenTextures(1)

# To use OpenGL 4.2 ARB_texture_storage to automatically generate a single mipmap layer

# uncomment the 3 lines below. Note that this should replaced glTexImage2D below.

#bind_texture(texture_id,'DEFAULT')

#glTexStorage2D(GL_TEXTURE_2D, 1, GL_RGBA8, width, height);

#glTexSubImage2D(GL_TEXTURE_2D,0,0,0,width,height,GL_RGBA,GL_UNSIGNED_BYTE,image)

# "Bind" the newly created texture : all future texture functions will modify this texture

bind_texture(texture_id,'MIN_FILTER')

glTexImage2D(

GL_TEXTURE_2D, 0, 3, width, height, 0,

GL_RGBA, GL_UNSIGNED_BYTE, image

)

if not opengl_init():

return

# Enable key events

glfw.set_input_mode(window,glfw.STICKY_KEYS,GL_TRUE)

# Set opengl clear color to something other than red (color used by the fragment shader)

glClearColor(0.0,0.0,0.4,0.0)

# Enable depth test

glEnable(GL_DEPTH_TEST);

# Accept fragment if it closer to the camera than the former one

glDepthFunc(GL_LESS);

vertex_array_id = glGenVertexArrays(1)

glBindVertexArray( vertex_array_id )

program_id = common.LoadShaders( ".\\shaders\\Tutorial5\\TransformVertexShader.vertexshader",

".\\shaders\\Tutorial5\\TextureFragmentShader.fragmentshader" )

# Get a handle for our "MVP" uniform

matrix_id = glGetUniformLocation(program_id, "MVP");

# Projection matrix : 45 Field of View, 4:3 ratio, display range : 0.1 unit <-> 100 units

projection = mat4.perspective(45.0, 4.0 / 3.0, 0.1, 100.0)

# Camera matrix

view = mat4.lookat(vec3(4,3,-3), # Camera is at (4,3,3), in World Space

vec3(0,0,0), # and looks at the origin

vec3(0,1,0))

# Model matrix : an identity matrix (model will be at the origin)

model = mat4.identity()

# Our ModelViewProjection : multiplication of our 3 matrices

mvp = projection * view * model

texture = load_image(".\\content\\uvtemplate.bmp")

texture_id = glGetUniformLocation(program_id, "myTextureSampler")

# Our vertices. Tree consecutive floats give a 3D vertex; Three consecutive vertices give a triangle.

# A cube has 6 faces with 2 triangles each, so this makes 6*2=12 triangles, and 12*3 vertices

vertex_data = [

-1.0,-1.0,-1.0,

-1.0,-1.0, 1.0,

-1.0, 1.0, 1.0,

1.0, 1.0,-1.0,

-1.0,-1.0,-1.0,

-1.0, 1.0,-1.0,

1.0,-1.0, 1.0,

-1.0,-1.0,-1.0,

1.0,-1.0,-1.0,

1.0, 1.0,-1.0,

1.0,-1.0,-1.0,

-1.0,-1.0,-1.0,

-1.0,-1.0,-1.0,

-1.0, 1.0, 1.0,

-1.0, 1.0,-1.0,

1.0,-1.0, 1.0,

-1.0,-1.0, 1.0,

-1.0,-1.0,-1.0,

-1.0, 1.0, 1.0,

-1.0,-1.0, 1.0,

1.0,-1.0, 1.0,

1.0, 1.0, 1.0,

1.0,-1.0,-1.0,

1.0, 1.0,-1.0,

1.0,-1.0,-1.0,

1.0, 1.0, 1.0,

1.0,-1.0, 1.0,

1.0, 1.0, 1.0,

1.0, 1.0,-1.0,

-1.0, 1.0,-1.0,

1.0, 1.0, 1.0,

-1.0, 1.0,-1.0,

-1.0, 1.0, 1.0,

1.0, 1.0, 1.0,

-1.0, 1.0, 1.0,

1.0,-1.0, 1.0]

# Two UV coordinatesfor each vertex. They were created withe Blender.

uv_data = [

0.000059, 1.0-0.000004,

0.000103, 1.0-0.336048,

0.335973, 1.0-0.335903,

1.000023, 1.0-0.000013,

0.667979, 1.0-0.335851,

0.999958, 1.0-0.336064,

0.667979, 1.0-0.335851,

0.336024, 1.0-0.671877,

0.667969, 1.0-0.671889,

1.000023, 1.0-0.000013,

0.668104, 1.0-0.000013,

0.667979, 1.0-0.335851,

0.000059, 1.0-0.000004,

0.335973, 1.0-0.335903,

0.336098, 1.0-0.000071,

0.667979, 1.0-0.335851,

0.335973, 1.0-0.335903,

0.336024, 1.0-0.671877,

1.000004, 1.0-0.671847,

0.999958, 1.0-0.336064,

0.667979, 1.0-0.335851,

0.668104, 1.0-0.000013,

0.335973, 1.0-0.335903,

0.667979, 1.0-0.335851,

0.335973, 1.0-0.335903,

0.668104, 1.0-0.000013,

0.336098, 1.0-0.000071,

0.000103, 1.0-0.336048,

0.000004, 1.0-0.671870,

0.336024, 1.0-0.671877,

0.000103, 1.0-0.336048,

0.336024, 1.0-0.671877,

0.335973, 1.0-0.335903,

0.667969, 1.0-0.671889,

1.000004, 1.0-0.671847,

0.667979, 1.0-0.335851]

vertex_buffer = glGenBuffers(1);

array_type = GLfloat * len(vertex_data)

glBindBuffer(GL_ARRAY_BUFFER, vertex_buffer)

glBufferData(GL_ARRAY_BUFFER, len(vertex_data) * 4, array_type(*vertex_data), GL_STATIC_DRAW)

uv_buffer = glGenBuffers(1);

array_type = GLfloat * len(uv_data)

glBindBuffer(GL_ARRAY_BUFFER, uv_buffer)

glBufferData(GL_ARRAY_BUFFER, len(uv_data) * 4, array_type(*uv_data), GL_STATIC_DRAW)

while glfw.get_key(window,glfw.KEY_ESCAPE) != glfw.PRESS and not glfw.window_should_close(window):

glClear(GL_COLOR_BUFFER_BIT| GL_DEPTH_BUFFER_BIT)

glUseProgram(program_id)

# Send our transformation to the currently bound shader,

# in the "MVP" uniform

glUniformMatrix4fv(matrix_id, 1, GL_FALSE,mvp.data)

# Bind our texture in Texture Unit 0

glActiveTexture(GL_TEXTURE0);

glBindTexture(GL_TEXTURE_2D, texture);

# Set our "myTextureSampler" sampler to user Texture Unit 0

glUniform1i(texture_id, 0);

#1rst attribute buffer : vertices

glEnableVertexAttribArray(0)

glBindBuffer(GL_ARRAY_BUFFER, vertex_buffer);

glVertexAttribPointer(

0, # attribute 0. No particular reason for 0, but must match the layout in the shader.

3, # len(vertex_data)

GL_FLOAT, # type

GL_FALSE, # ormalized?

0, # stride

null # array buffer offset (c_type == void*)

)

# 2nd attribute buffer : colors

glEnableVertexAttribArray(1)

glBindBuffer(GL_ARRAY_BUFFER, uv_buffer);

glVertexAttribPointer(

1, # attribute 0. No particular reason for 0, but must match the layout in the shader.

2, # len(vertex_data)

GL_FLOAT, # type

GL_FALSE, # ormalized?

0, # stride

null # array buffer offset (c_type == void*)

)

# Draw the triangle !

glDrawArrays(GL_TRIANGLES, 0, 12*3) #3 indices starting at 0 -> 1 triangle

# Not strictly necessary because we only have

glDisableVertexAttribArray(0)

glDisableVertexAttribArray(1)

# Swap front and back buffers

glfw.swap_buffers(window)

# Poll for and process events

glfw.poll_events()

# note braces around vertex_buffer and vertex_array_id.

# These 2 functions expect arrays of values

glDeleteBuffers(1, [vertex_buffer])

glDeleteBuffers(1, [uv_buffer])

glDeleteProgram(program_id)

glDeleteTextures([texture_id])

glDeleteVertexArrays(1, [vertex_array_id])