//
// 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 render(w *glfw.Window, r *gResources) {
/*
width, height := w.GetFramebufferSize()
gl.Viewport(0, 0, int32(width), int32(height))
gl.Clear(gl.COLOR_BUFFER_BIT)
gl.MatrixMode(gl.PROJECTION)
gl.LoadIdentity()
gl.MatrixMode(gl.MODELVIEW)
gl.LoadIdentity()
*/
////////////////
gl.UseProgram(r.program)
gl.Uniform1f(r.uniforms.fadeFactor, r.fadeFactor)
gl.ActiveTexture(gl.TEXTURE0)
gl.BindTexture(gl.TEXTURE_2D, r.textures[0])
gl.Uniform1i(r.uniforms.textures[0], 0)
gl.ActiveTexture(gl.TEXTURE1)
gl.BindTexture(gl.TEXTURE_2D, r.textures[1])
gl.Uniform1i(r.uniforms.textures[1], 1)
gl.BindBuffer(gl.ARRAY_BUFFER, r.vertexBuffer)
gl.VertexAttribPointer(
uint32(r.attributes.position), /* attribute */
2, /* size */
gl.FLOAT, /* type */
false, /* normalized? */
8, /* stride */
gl.PtrOffset(0)) /* array buffer offset */
gl.EnableVertexAttribArray(uint32(r.attributes.position))
gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, r.elementBuffer)
gl.DrawElements(
gl.TRIANGLE_STRIP, /* mode */
4, /* count */
gl.UNSIGNED_INT, /* type */
gl.PtrOffset(0)) /* element array buffer offset */
gl.DisableVertexAttribArray(uint32(r.attributes.position))
}
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)
}
func (glr *GlRenderer) Start() {
go func() {
glr.initSystem()
glr.initScreen()
// Prepare 2 frames to double buffer
for i := 0; i < 2; i++ {
glr.freeFrames <- &Frame{
glr.window.ShouldClose(),
make([]maths.Rgba, glr.width*glr.height),
glr.width, glr.height}
}
// Loop until stop is requested
for nextFrame := range glr.framesToRender {
if nextFrame.ShouldStop {
break
}
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
gl.UseProgram(glr.program)
gl.BindVertexArray(glr.vao)
updateScreenTexture(glr.texture, nextFrame.Pixels, glr.width, glr.height)
gl.DrawArrays(gl.TRIANGLES, 0, 6)
glr.window.SwapBuffers()
glfw.PollEvents()
// Consider frame rendered, so push back to be reused
nextFrame.ShouldStop = glr.window.ShouldClose()
glr.freeFrames <- nextFrame
}
}()
}
//
// DisableShader
// Sets the Active Shader to 0 (none)
//
func (shaderManager *ShaderManager) DisableShader() {
gl.UseProgram(0)
shaderManager.ActiveShader = ""
}
//
// EnableShader
// Sets the Active Shader to the one given
//
// @param name (string) the name of the shader to enable
//
func (shaderManager *ShaderManager) EnableShader(name string) {
gl.UseProgram(shaderManager.Shaders[name].Shader)
shaderManager.ActiveShader = name
}
func render(w *glfw.Window, r *gResources) {
width, height := w.GetFramebufferSize()
ratio := float32(width) / float32(height)
var xmul, ymul float32
if ratio > 1 {
xmul, ymul = ra/ratio, ra
} else {
xmul, ymul = ra, ra*ratio
}
d := time.Since(start).Seconds()
sin := float32(math.Sin(d))
cos := float32(math.Cos(d))
gl.Viewport(0, 0, int32(width), int32(height))
gl.Clear(gl.COLOR_BUFFER_BIT)
////////////////
// axes
gl.UseProgram(r.program1)
gl.BindBuffer(gl.ARRAY_BUFFER, r.vertexBuffer1)
gl.VertexAttribPointer(
uint32(r.attributes1.position), // attribute
2, // size
gl.FLOAT, // type
false, // normalized?
8, // stride
gl.PtrOffset(0)) // array buffer offset
gl.EnableVertexAttribArray(uint32(r.attributes1.position))
gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, r.elementBuffer1)
gl.LineWidth(1)
gl.DrawElements(
gl.LINES, // mode
4, // count
gl.UNSIGNED_INT, // type
gl.PtrOffset(0)) // element array buffer offset
gl.DisableVertexAttribArray(uint32(r.attributes1.position))
////////////////
// triangle
gl.UseProgram(r.program2)
gl.Uniform1f(r.uniforms2.xmul, xmul)
gl.Uniform1f(r.uniforms2.ymul, ymul)
gl.Uniform1f(r.uniforms2.sin, sin)
gl.Uniform1f(r.uniforms2.cos, cos)
gl.BindBuffer(gl.ARRAY_BUFFER, r.vertexBuffer2)
gl.VertexAttribPointer(
uint32(r.attributes2.position), // attribute
2, // size
gl.FLOAT, // type
false, // normalized?
8, // stride
gl.PtrOffset(0)) // array buffer offset
gl.EnableVertexAttribArray(uint32(r.attributes2.position))
gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, r.elementBuffer2)
gl.EnableVertexAttribArray(uint32(r.attributes2.color))
gl.BindBuffer(gl.ARRAY_BUFFER, r.colorBuffer2)
gl.VertexAttribPointer(
uint32(r.attributes2.color), // attribute
3, // size
gl.FLOAT, // type
false, // normalized?
0, // stride
gl.PtrOffset(0)) // array buffer offset
gl.DrawElements(
gl.TRIANGLES, // mode
3, // count
gl.UNSIGNED_INT, // type
gl.PtrOffset(0)) // element array buffer offset
////////////////
// circle
gl.BindBuffer(gl.ARRAY_BUFFER, r.vertexBuffer3)
gl.VertexAttribPointer(
uint32(r.attributes2.position), // attribute
2, // size
gl.FLOAT, // type
false, // normalized?
8, // stride
gl.PtrOffset(0)) // array buffer offset
gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, r.elementBuffer3)
gl.BindBuffer(gl.ARRAY_BUFFER, r.colorBuffer3)
gl.VertexAttribPointer(
uint32(r.attributes2.color), // attribute
3, // size
gl.FLOAT, // type
false, // normalized?
0, // stride
gl.PtrOffset(0)) // array buffer offset
gl.LineWidth(5)
gl.DrawElements(
gl.LINE_LOOP, // mode
r.len3, // count
gl.UNSIGNED_INT, // type
gl.PtrOffset(0)) // element array buffer offset
gl.DisableVertexAttribArray(uint32(r.attributes2.color))
gl.DisableVertexAttribArray(uint32(r.attributes2.position))
}
func createProgram(vertexShaderFile, fragmentShaderFile string, uniforms, attributes []string) (*Shader, error) {
// Configure the vertex and fragment shaders
vertexShaderSource, err := ioutil.ReadFile(vertexShaderFile)
vertexShaderSource = append(vertexShaderSource, 0x00)
fragmentShaderSource, err := ioutil.ReadFile(fragmentShaderFile)
fragmentShaderSource = append(fragmentShaderSource, 0x00)
vertexShader, err := compileShader(string(vertexShaderSource), gl.VERTEX_SHADER)
if err != nil {
return nil, err
}
fragmentShader, err := compileShader(string(fragmentShaderSource), gl.FRAGMENT_SHADER)
if err != nil {
return nil, err
}
program := gl.CreateProgram()
gl.AttachShader(program, vertexShader)
gl.AttachShader(program, fragmentShader)
gl.LinkProgram(program)
var status int32
gl.GetProgramiv(program, gl.LINK_STATUS, &status)
if status == gl.FALSE {
var logLength int32
gl.GetProgramiv(program, gl.INFO_LOG_LENGTH, &logLength)
log := strings.Repeat("\x00", int(logLength+1))
gl.GetProgramInfoLog(program, logLength, nil, gl.Str(log))
return nil, fmt.Errorf("failed to link program: %v", log)
}
gl.DeleteShader(vertexShader)
gl.DeleteShader(fragmentShader)
gl.UseProgram(program)
programUniforms := make(map[string]int32)
for _, uniformName := range uniforms {
if uniformName != "" {
glstr := gl.Str(uniformName + "\x00")
programUniforms[uniformName] = gl.GetUniformLocation(program, glstr)
}
}
programAttributes := make(map[string]uint32)
for _, attribName := range attributes {
if attribName != "" {
glstr := gl.Str(attribName + "\x00")
programAttributes[attribName] = uint32(gl.GetAttribLocation(program, glstr))
}
}
return &Shader{
program: program,
uniforms: programUniforms,
attributes: programAttributes,
}, nil
}