//
// Draw Loop Function
// This function gets called on every update.
//
func drawLoop(glw *wrapper.Glw) {
// Sets the Clear Color (Background Color)
gl.ClearColor(0.0, 0.0, 0.0, 1.0)
// Clears the Window
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
// Enables Depth
gl.Enable(gl.DEPTH_TEST)
// Sets the Shader program to Use
gl.UseProgram(shaderProgram)
// Define the model transformations for the cube
cube.ResetModel()
cube.Translate(x+0.5, y, z)
cube.Scale(scale, scale, scale) //scale equally in all axis
cube.Rotate(-angle_x, mgl32.Vec3{1, 0, 0}) //rotating in clockwise direction around x-axis
cube.Rotate(-angle_y, mgl32.Vec3{0, 1, 0}) //rotating in clockwise direction around y-axis
cube.Rotate(-angle_z, mgl32.Vec3{0, 0, 1}) //rotating in clockwise direction around z-axis
// Define the model transformations for our sphere
sphere.ResetModel()
sphere.Translate(-x-0.5, 0, 0)
sphere.Scale(scale/3.0, scale/3.0, scale/3.0) //scale equally in all axis
sphere.Rotate(-angle_x, mgl32.Vec3{1, 0, 0}) //rotating in clockwise direction around x-axis
sphere.Rotate(-angle_y, mgl32.Vec3{0, 1, 0}) //rotating in clockwise direction around y-axis
sphere.Rotate(-angle_z, mgl32.Vec3{0, 0, 1}) //rotating in clockwise direction around z-axis
// Projection matrix : 45° Field of View, 4:3 ratio, display range : 0.1 unit <-> 100 units
var Projection mgl32.Mat4 = mgl32.Perspective(30.0, aspect_ratio, 0.1, 100.0)
// Camera matrix
var View mgl32.Mat4 = mgl32.LookAtV(
mgl32.Vec3{0, 0, 4}, // Camera is at (0,0,4), in World Space
mgl32.Vec3{0, 0, 0}, // and looks at the origin
mgl32.Vec3{0, 1, 0}, // Head is up (set to 0,-1,0 to look upside-down)
)
// Send our uniforms variables to the currently bound shader,
gl.Uniform1ui(colourmodeUniform, uint32(colourmode))
gl.UniformMatrix4fv(viewUniform, 1, false, &View[0])
gl.UniformMatrix4fv(projectionUniform, 1, false, &Projection[0])
// Draws the Cube
gl.UniformMatrix4fv(modelUniform, 1, false, &cube.Model[0])
cube.Draw()
// Draw our sphere
gl.UniformMatrix4fv(modelUniform, 1, false, &sphere.Model[0])
sphere.DrawSphere()
gl.DisableVertexAttribArray(0)
gl.UseProgram(0)
/* Modify our animation variables */
angle_x += angle_inc_x
angle_y += angle_inc_y
angle_z += angle_inc_z
}
func (r *Renderer) Render() {
// defer glfw.Terminate()
shader := r.Shaders.textureFlat
program := shader.program
//
gl.UseProgram(program)
//
gl.BindFragDataLocation(program, 0, gl.Str("outputColor\x00"))
// // Configure global settings
gl.Enable(gl.DEPTH_TEST)
gl.DepthFunc(gl.LESS)
gl.ClearColor(1.0, 1.0, 1.0, 1.0)
//
// angle += elapsed
// r.Mesh.modelView = mgl32.HomogRotate3D(float32(angle), mgl32.Vec3{0, 1, 0})
// Render
// gl.UniformMatrix4fv(shader.uniforms["modelView"], 1, false, &r.Mesh.modelView[0])
time := glfw.GetTime()
_ = time - r.PreviousTime
r.PreviousTime = time
// fmt.Println(elapsed * 100)
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
gl.UniformMatrix4fv(shader.uniforms["projection"], 1, false, &r.Projection[0])
gl.UniformMatrix4fv(shader.uniforms["camera"], 1, false, &r.Camera[0])
// TODO : batch triangles and use multiple textures
for _, mesh := range r.Meshes {
gl.UniformMatrix4fv(shader.uniforms["modelView"], 1, false, &mesh.modelView[0])
gl.Uniform1i(shader.uniforms["tex"], 0)
gl.BindVertexArray(mesh.vao)
gl.ActiveTexture(gl.TEXTURE0)
gl.BindTexture(gl.TEXTURE_2D, mesh.textures[0])
gl.DrawArrays(gl.TRIANGLES, 0, int32(len(mesh.verticies)/5))
}
// Maintenance
r.Window.SwapBuffers()
glfw.PollEvents()
if r.Ready == false {
r.Ready = true
}
}
func (glr *GlRenderer) initScreen() {
var err error
glr.program, err = createScreenShader()
if err != nil {
panic(err)
}
gl.UseProgram(glr.program)
projection := mgl32.Ortho2D(-1, 1, 1, -1)
projectionUniform := gl.GetUniformLocation(glr.program, gl.Str("projection\x00"))
gl.UniformMatrix4fv(projectionUniform, 1, false, &projection[0])
textureUniform := gl.GetUniformLocation(glr.program, gl.Str("tex\x00"))
gl.Uniform1i(textureUniform, 0)
glr.texture = createScreenTexture(glr.width, glr.height)
gl.GenVertexArrays(1, &glr.vao)
gl.BindVertexArray(glr.vao)
var quadVertices = []float32{
// X, Y, Z, U, V
1.0, -1.0, 0.0, 1.0, 0.0,
-1.0, -1.0, 0.0, 0.0, 0.0,
1.0, 1.0, 0.0, 1.0, 1.0,
-1.0, -1.0, 0.0, 0.0, 0.0,
-1.0, 1.0, 0.0, 0.0, 1.0,
1.0, 1.0, 0.0, 1.0, 1.0,
}
var vbo uint32
gl.GenBuffers(1, &vbo)
gl.BindBuffer(gl.ARRAY_BUFFER, vbo)
gl.BufferData(gl.ARRAY_BUFFER, len(quadVertices)*4, gl.Ptr(quadVertices), gl.STATIC_DRAW)
vertAttrib := uint32(gl.GetAttribLocation(glr.program, gl.Str("vert\x00")))
gl.EnableVertexAttribArray(vertAttrib)
gl.VertexAttribPointer(vertAttrib, 3, gl.FLOAT, false, 5*4, gl.PtrOffset(0))
texCoordAttrib := uint32(gl.GetAttribLocation(glr.program, gl.Str("vertTexCoord\x00")))
gl.EnableVertexAttribArray(texCoordAttrib)
gl.VertexAttribPointer(texCoordAttrib, 2, gl.FLOAT, false, 5*4, gl.PtrOffset(3*4))
gl.Enable(gl.DEPTH_TEST)
gl.ClearColor(1.0, 1.0, 1.0, 1.0)
}
//
// Create Window
// This creates a window, initiates GL and sets the event listeners
//
// @return window (*glfw.Window) pointer to the window
//
func (glw *Glw) CreateWindow() *glfw.Window {
// Init GLFW
if err := glfw.Init(); err != nil {
log.Fatalln("failed to initialize glfw:", err)
}
// Sets the OpenGL Version
setOpenGlVersion()
// Creates the Window
win, err := glfw.CreateWindow(glw.Width, glw.Height, glw.Title, nil, nil)
if err != nil {
panic(err)
}
// Prints the OpenGL Versions at the end
defer printOpenGlVersionInfo()
// Sets this context as the current context
win.MakeContextCurrent()
// Initiates GL
if err := gl.Init(); err != nil {
panic(err)
}
// Enables Depth
gl.Enable(gl.DEPTH_TEST)
gl.DepthFunc(gl.LESS)
win.SetInputMode(glfw.StickyKeysMode, 1)
// Sets the Window to the Wrapper
glw.SetWindow(win)
return win
}
func (objectLoader *WavefrontObject) DrawObject(shaderProgram uint32) {
for _, object := range objectLoader.Objects {
// Reads the uniform Locations
modelUniform := gl.GetUniformLocation(shaderProgram, gl.Str("model\x00"))
ambientUniform := gl.GetUniformLocation(shaderProgram, gl.Str("ambient\x00"))
diffuseUniform := gl.GetUniformLocation(shaderProgram, gl.Str("diffuse\x00"))
specularUniform := gl.GetUniformLocation(shaderProgram, gl.Str("specular\x00"))
emissiveUniform := gl.GetUniformLocation(shaderProgram, gl.Str("emissive\x00"))
// Send our uniforms variables to the currently bound shader
if object.Material != nil {
gl.Uniform4f(ambientUniform, object.Material.KaR, object.Material.KaG, object.Material.KaB, object.Material.Tr) // Ambient colour.
gl.Uniform4f(diffuseUniform, object.Material.KdR, object.Material.KdG, object.Material.KdB, object.Material.Tr) // Diffuse colour.
gl.Uniform4f(specularUniform, object.Material.KsR, object.Material.KsG, object.Material.KsB, object.Material.Tr) // Specular colour.
gl.Uniform4f(emissiveUniform, object.Material.KeR, object.Material.KeG, object.Material.KeB, object.Material.Tr) // Emissive colour.
if object.Material.Texture != 0 {
textureUniform := gl.GetUniformLocation(shaderProgram, gl.Str("DiffuseTextureSampler\x00"))
gl.Uniform1i(textureUniform, 0)
normalTextureUniform := gl.GetUniformLocation(shaderProgram, gl.Str("NormalTextureSampler\x00"))
gl.Uniform1i(normalTextureUniform, 1)
specularTextureUniform := gl.GetUniformLocation(shaderProgram, gl.Str("SpecularTextureSampler\x00"))
gl.Uniform1i(specularTextureUniform, 2)
gl.ActiveTexture(gl.TEXTURE0)
gl.BindTexture(gl.TEXTURE_2D, object.Material.Texture)
gl.ActiveTexture(gl.TEXTURE1)
gl.BindTexture(gl.TEXTURE_2D, object.Material.NormalMap)
gl.ActiveTexture(gl.TEXTURE2)
gl.BindTexture(gl.TEXTURE_2D, object.Material.SpecularMap)
}
if object.Material.Tr < 1.0 {
// Enables Transparencies
gl.Enable(gl.BLEND)
// gl.BlendFunc(gl.SRC_COLOR, gl.ONE)
// gl.BlendFunc(gl.ONE, gl.ONE_MINUS_SRC_ALPHA)
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
}
}
// Geometry
var size int32 // Used to get the byte size of the element (vertex index) array
gl.UniformMatrix4fv(modelUniform, 1, false, &object.Model[0])
// Get the vertices uniform position
verticesUniform := uint32(gl.GetAttribLocation(shaderProgram, gl.Str("position\x00")))
normalsUniform := uint32(gl.GetAttribLocation(shaderProgram, gl.Str("normal\x00")))
textureCoordinatesUniform := uint32(gl.GetAttribLocation(shaderProgram, gl.Str("texcoord\x00")))
// Describe our vertices array to OpenGL (it can't guess its format automatically)
gl.BindBuffer(gl.ARRAY_BUFFER, object.VertexBufferObjectVertices)
gl.VertexAttribPointer(
verticesUniform, // attribute index
3, // number of elements per vertex, here (x,y,z)
gl.FLOAT, // the type of each element
false, // take our values as-is
0, // no extra data between each position
nil, // offset of first element
)
gl.EnableVertexAttribArray(normalsUniform)
gl.BindBuffer(gl.ARRAY_BUFFER, object.VertexBufferObjectNormals)
gl.VertexAttribPointer(
normalsUniform, // attribute
3, // number of elements per vertex, here (x,y,z)
gl.FLOAT, // the type of each element
false, // take our values as-is
0, // no extra data between each position
nil, // offset of first element
)
gl.EnableVertexAttribArray(textureCoordinatesUniform)
gl.BindBuffer(gl.ARRAY_BUFFER, object.VertexBufferObjectTextureCoords)
gl.VertexAttribPointer(
textureCoordinatesUniform, // attribute
2, // number of elements per vertex, here (u,v)
gl.FLOAT, // the type of each element
false, // take our values as-is
0, // no extra data between each position
nil, // offset of first element
)
size = int32(len(object.Vertex))
gl.PointSize(3.0)
// Enable this line to show model in wireframe
switch objectLoader.DrawMode {
case 1:
gl.PolygonMode(gl.FRONT_AND_BACK, gl.LINE)
default:
gl.PolygonMode(gl.FRONT_AND_BACK, gl.FILL)
}
gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, object.VertexBufferObjectFaces)
gl.GetBufferParameteriv(gl.ELEMENT_ARRAY_BUFFER, gl.BUFFER_SIZE, &size)
gl.DrawElements(gl.TRIANGLES, int32(len(object.Faces)), gl.UNSIGNED_SHORT, nil)
// gl.DrawElements(gl.POINTS, int32(len(object.Faces)), gl.UNSIGNED_SHORT, nil)
// Disables transparencies
gl.Disable(gl.BLEND)
}
}