Files
i-mic-fps/lib/renderer/shader.rb

127 lines
3.6 KiB
Ruby

class IMICFPS
# Ref: https://github.com/vaiorabbit/ruby-opengl/blob/master/sample/OrangeBook/brick.rb
class Shader
include OpenGL
def initialize(name:, vertex_file:, fragment_file:)
@name = name
@vertex_file = vertex_file
@fragment_file = fragment_file
@compiled = false
@error_buffer_size = 1024
@variable_missing = {}
create_shaders
compile_shaders
# Only add shader to ShaderManager if it successfully compiles
if @compiled
ShaderManager.add_shader(@name, self)
else
puts "FAILED to compile shader: #{@name}", ""
end
end
def shader_files_exist?
File.exists?(@vertex_file) && File.exists?(@fragment_file)
end
def create_shaders
return unless shader_files_exist?
@vertex = glCreateShader(GL_VERTEX_SHADER)
@fragment = glCreateShader(GL_FRAGMENT_SHADER)
source = [File.read(@vertex_file)].pack('p')
size = [File.size(@vertex_file)].pack('I')
glShaderSource(@vertex, 1, source, size)
source = [File.read(@fragment_file)].pack('p')
size = [File.size(@fragment_file)].pack('I')
glShaderSource(@fragment, 1, source, size)
end
def compile_shaders
return unless shader_files_exist?
glCompileShader(@vertex)
buffer = ' '
glGetShaderiv(@vertex, GL_COMPILE_STATUS, buffer)
compiled = buffer.unpack('L')[0]
if compiled == 0
log = ' ' * @error_buffer_size
glGetShaderInfoLog(@vertex, @error_buffer_size, nil, log)
puts "Shader Error: Program \"#{@name}\""
puts " Vertex Shader InfoLog:", " #{log.strip.split("\n").join("\n ")}\n\n"
puts " Shader Compiled status: #{compiled}"
puts " NOTE: assignment of uniforms in shaders is illegal!"
puts
return
end
glCompileShader(@fragment)
buffer = ' '
glGetShaderiv(@fragment, GL_COMPILE_STATUS, buffer)
compiled = buffer.unpack('L')[0]
if compiled == 0
log = ' ' * @error_buffer_size
glGetShaderInfoLog(@fragment, @error_buffer_size, nil, log)
puts "Shader Error: Program \"#{@name}\""
puts " Fragment Shader InfoLog:", " #{log.strip.split("\n").join("\n ")}\n\n"
puts " Shader Compiled status: #{compiled}"
puts " NOTE: assignment of uniforms in shader is illegal!"
puts
return
end
@program = glCreateProgram
glAttachShader(@program, @vertex)
glAttachShader(@program, @fragment)
glLinkProgram(@program)
buffer = ' '
glGetProgramiv(@program, GL_LINK_STATUS, buffer)
linked = buffer.unpack('L')[0]
if linked == 0
log = ' ' * @error_buffer_size
glGetProgramInfoLog(@program, @error_buffer_size, nil, log)
puts "Shader Error: Program \"#{@name}\""
puts " Program InfoLog:", " #{log.strip.split("\n").join("\n ")}\n\n"
end
@compiled = linked == 0 ? false : true
end
# Returns the location of a uniform variable
def variable(variable)
loc = glGetUniformLocation(@program, variable)
if (loc == -1)
puts "Shader Error: Program \"#{@name}\" has no such uniform named \"#{variable}\"", " Is it used in the shader? GLSL may have optimized it out.", " Is it miss spelled?" unless @variable_missing[variable]
@variable_missing[variable] = true
end
return loc
end
def use(&block)
return unless compiled?
glUseProgram(@program)
if block
block.call(self)
stop
end
end
def stop
glUseProgram(0)
end
def compiled?
@compiled
end
end
end