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#========================================================================
# test.pl is basically the simple GLFW example renamed so it runs
# after the test suite so you see something if the build worked.
#========================================================================
BEGIN { exit }
# skip test under under headless CI
exit if exists $ENV{CI} and $^O eq 'darwin' or $^O eq 'MSWin32';
#========================================================================
# Simple GLFW example
# Copyright (c) Camilla Berglund <elmindreda@glfw.org>
#
# This software is provided 'as-is', without any express or implied
# warranty. In no event will the authors be held liable for any damages
# arising from the use of this software.
#
# Permission is granted to anyone to use this software for any purpose,
# including commercial applications, and to alter it and redistribute it
# freely, subject to the following restrictions:
#
# 1. The origin of this software must not be misrepresented; you must not
# claim that you wrote the original software. If you use this software
# in a product, an acknowledgment in the product documentation would
# be appreciated but is not required.
#
# 2. Altered source versions must be plainly marked as such, and must not
# be misrepresented as being the original software.
#
# 3. This notice may not be removed or altered from any source
# distribution.
#
#========================================================================
#========================================================================
# OpenGL routines used:
#
# glAttachShader
# glBindBuffer
# glClear
# glCompileShader
# glCreateProgram
# glCreateShader
# glDrawArrays
# glEnableVertexAttribArray
# glLinkProgram
# glUseProgram
# glViewport
#
# glGetAttribLocation
# glGetUniformLocation
# glUniformMatrix4fv_c
# glVertexAttribPointer_c
#
# glBufferData_p
# glGenBuffers_p
# glGenBuffers_p
# glShaderSource_p
#========================================================================
use OpenGL::GLFW qw(:all);
use OpenGL::Modern qw(:all);
use OpenGL::Modern::Helpers qw(glGenBuffers_p glBufferData_p);
# #include "linmath.h"
# x y r g b
my @vertices = ( -0.6, -0.4, 1.0, 0.0, 0.0,
0.6, -0.4, 0.0, 1.0, 0.0,
0.0, 0.6, 0.0, 0.0, 1.0 );
my @vertex_shader_text = (
"uniform mat4 MVP;\n",
"attribute vec3 vCol;\n",
"attribute vec2 vPos;\n",
"varying vec3 color;\n",
"void main()\n",
"{\n",
" gl_Position = MVP * vec4(vPos, 0.0, 1.0);\n",
" color = vCol;\n",
"}\n"
);
my @fragment_shader_text = (
"varying vec3 color;\n",
"void main()\n",
"{\n",
" gl_FragColor = vec4(color, 1.0);\n",
"}\n",
);
# my $drop_callback = sub {
# my ($window, @paths) = @_;
# print "Dropped (@paths)\n";
# };
my $error_callback = sub {
my ($error, $description) = @_;
printf STDERR "Error #%d from perl: %s\n", $error, $description;
};
my $key_callback = sub {
my ($window, $key, $scancode, $action, $mods) = @_;
if ($key == GLFW_KEY_ESCAPE && $action == GLFW_PRESS) {
glfwSetWindowShouldClose($window, GLFW_TRUE);
}
};
# int main(void) {
#
my ($window);
my ($vertex_buffer, $vertex_shader, $fragment_shader, $program);
my ($mvp_location, $vpos_location, $vcol_location);
glfwSetErrorCallback($error_callback);
die "glfwInit failed, $!\n" if !glfwInit();
# glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
# glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
# TODO: implement NULL pointer (is 0 or undef enough?)
# $window = glfwCreateWindow(640, 480, "Simple example", NULL, NULL);
#
$window = glfwCreateWindow(640, 480, "Simple example", NULL, NULL);
unless (defined $window) {
glfwTerminate();
die "glfwCreateWindow failed, $!\n";
}
glfwSetKeyCallback($window, $key_callback);
# TODO: It looks like you cant Drag-and-Drop between windows Explorer
# and cygwin X11 applications. Need to test for linux and for win32
# native
#
# glfwSetDropCallback($window, $drop_callback);
glfwMakeContextCurrent($window);
die "glewInit failed, $!\n" if GLEW_OK != glewInit();
glfwSwapInterval(1);
#-----------------------------------------------------------
# NOTE: OpenGL error checks have been omitted for brevity
#-----------------------------------------------------------
my $vertex_buffer = glGenBuffers_p(1); # TODO
glBindBuffer(GL_ARRAY_BUFFER, $vertex_buffer);
# glBufferData_p(GL_ARRAY_BUFFER, sizeof(@vertices), @vertices, GL_STATIC_DRAW); # TODO
glBufferData_p(GL_ARRAY_BUFFER, 4*scalar(@vertices), @vertices, GL_STATIC_DRAW); # TODO
my $vertex_shader = glCreateShader(GL_VERTEX_SHADER);
glShaderSource_p($vertex_shader, @vertex_shader_text); # TODO
glCompileShader($vertex_shader);
my $fragment_shader = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource_p($fragment_shader, @fragment_shader_text); # TODO
glCompileShader($fragment_shader);
my $program = glCreateProgram();
glAttachShader($program, $vertex_shader);
glAttachShader($program, $fragment_shader);
glLinkProgram($program);
my $mvp_location = glGetUniformLocation($program, "MVP"); # TODO change name to _p or no-suffix
my $vpos_location = glGetAttribLocation($program, "vPos"); # TODO change name to _p or no-suffix
my $vcol_location = glGetAttribLocation($program, "vCol"); # TODO change name to _p or no-suffix
glEnableVertexAttribArray($vpos_location);
#------------------------------------------------------------ stride, offset
glVertexAttribPointer_c($vpos_location, 2, GL_FLOAT, GL_FALSE, 4 * 5, 0 );
glEnableVertexAttribArray($vcol_location);
#------------------------------------------------------------ stride, offset
glVertexAttribPointer_c($vcol_location, 3, GL_FLOAT, GL_FALSE, 4 * 5, 4 * 2 );
while (!glfwWindowShouldClose($window) and glfwGetTime()<3)
{
my ($width, $height);
my ($angle, $c, $s, $cor, $sor);
# mat4x4 $m, $p, $mvp; # TODO
my ($width, $height) = glfwGetFramebufferSize($window);
my $ratio = $width / $height;
glViewport(0, 0, $width, $height);
glClear(GL_COLOR_BUFFER_BIT);
# $m = mat4x4_identity(); # TODO
# $m = mat4x4_rotate_Z($m, glfwGetTime()); # TODO
$angle = glfwGetTime();
$c = cos($angle);
$cor = $c/$ratio;
$s = sin($angle);
$sor = $s/$ratio;
# $p = mat4x4_ortho(-$ratio, $ratio, -1.0, 1.0, 1.0, -1.0); # TODO
# hardwired rotation and orthographic projection MVP matrix
my $mvp = pack 'f[16]', $cor, $s, 0, 0, -$sor, $c, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1;
my $pointer_to_mvp_data = unpack 'Q', pack 'P', $mvp;
glUseProgram($program);
glUniformMatrix4fv_c($mvp_location, 1, GL_FALSE, $pointer_to_mvp_data); # TODO
glDrawArrays(GL_TRIANGLES, 0, 3);
glfwSwapBuffers($window);
glfwPollEvents();
}
glfwDestroyWindow($window);
glfwTerminate();
#
# }
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