func CreateBuffers() {
var err error
program, err = MakeProgram(VertexShader(), FragmentShader())
// defer program.Delete()
if err != nil {
fmt.Println("Error loading shaders: " + err.Error())
panic("error loading shaders")
}
gl.BindFragDataLocation(program, 0, gl.Str("color\x00"))
MVPid = gl.GetUniformLocation(program, gl.Str("MVP\x00"))
lightpositionID = gl.GetUniformLocation(program, gl.Str("light.position\x00"))
lightintensitiesID = gl.GetUniformLocation(program, gl.Str("light.intensities\x00"))
lightattenuationID = gl.GetUniformLocation(program, gl.Str("light.attenuation\x00"))
lightambientCoeficientID = gl.GetUniformLocation(program, gl.Str("light.ambientCoeficient\x00"))
cameraPositionID = gl.GetUniformLocation(program, gl.Str("cameraPosition\x00"))
// View := mathgl.LookAt(0.0, 0.0, 5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0)
// viewM = View
gl.DepthFunc(gl.LEQUAL)
gl.Enable(gl.BLEND)
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
// var vao uint32
gl.GenVertexArrays(1, &vao)
gl.BindVertexArray(vao)
// var vbo uint32
gl.GenBuffers(1, &vbo)
// gl.GenBuffers(1, &elementvbo)
// fmt.Println(program)
gl.UseProgram(program)
for idx, img := range aggregateImages {
bindAggregateImage(img, idx)
}
}
func CreateContext(width, height int) Context {
vertexShader := `
#version 330
uniform mat4 projection;
uniform mat4 camera;
uniform mat4 model;
in vec3 vert;
void main() {
gl_Position = projection * camera * model * vec4(vert, 1);
}
` + "\x00"
fragmentShader := `
#version 330
uniform vec4 color;
out vec4 outputColor;
void main() {
outputColor = color;
}
` + "\x00"
vertices := []float32{
0.0, 0.0, 0.0,
1.0, 0.0, 0.0,
1.0, 1.0, 0.0,
1.0, 1.0, 0.0,
0.0, 1.0, 0.0,
0.0, 0.0, 0.0,
}
if err := glfw.Init(); err != nil {
log.Fatalln("failed to initialize glfw:", err)
}
// defer glfw.Terminate()
glfw.WindowHint(glfw.Resizable, glfw.False)
glfw.WindowHint(glfw.ContextVersionMajor, 3)
glfw.WindowHint(glfw.ContextVersionMinor, 3)
glfw.WindowHint(glfw.OpenGLProfile, glfw.OpenGLCoreProfile)
glfw.WindowHint(glfw.OpenGLForwardCompatible, glfw.True)
window, err := glfw.CreateWindow(width, height, "OpenGL", nil, nil)
if err != nil {
panic(err)
}
window.MakeContextCurrent()
if err := gl.Init(); err != nil {
panic(err)
}
program, err := newProgram(vertexShader, fragmentShader)
if err != nil {
panic(err)
}
gl.UseProgram(program)
projection := mgl32.Ortho2D(0, 800, 0, 600)
projectionUniform := gl.GetUniformLocation(program, gl.Str("projection\x00"))
gl.UniformMatrix4fv(projectionUniform, 1, false, &projection[0])
camera := mgl32.LookAtV(mgl32.Vec3{0, 0, 0.5}, mgl32.Vec3{0, 0, 0}, mgl32.Vec3{0, 1, 0})
cameraUniform := gl.GetUniformLocation(program, gl.Str("camera\x00"))
gl.UniformMatrix4fv(cameraUniform, 1, false, &camera[0])
model := mgl32.Ident4()
modelUniform := gl.GetUniformLocation(program, gl.Str("model\x00"))
gl.UniformMatrix4fv(modelUniform, 1, false, &model[0])
var vao uint32
gl.GenVertexArrays(1, &vao)
gl.BindVertexArray(vao)
var vbo uint32
gl.GenBuffers(1, &vbo)
gl.BindBuffer(gl.ARRAY_BUFFER, vbo)
gl.BufferData(gl.ARRAY_BUFFER, len(vertices)*4, gl.Ptr(vertices), gl.STATIC_DRAW)
vertAttrib := uint32(gl.GetAttribLocation(program, gl.Str("vert\x00")))
gl.EnableVertexAttribArray(vertAttrib)
gl.VertexAttribPointer(vertAttrib, 3, gl.FLOAT, false, 3*4, gl.PtrOffset(0))
gl.Enable(gl.DEPTH_TEST)
gl.DepthFunc(gl.LESS)
return Context{Window: window, program: program}
}
func main() {
// init glfw
if err := glfw.Init(); err != nil {
panic(err)
}
defer glfw.Terminate()
glfw.WindowHint(glfw.Resizable, glfw.False)
glfw.WindowHint(glfw.ContextVersionMajor, 4)
glfw.WindowHint(glfw.ContextVersionMinor, 1)
glfw.WindowHint(glfw.OpenGLProfile, glfw.OpenGLCoreProfile)
glfw.WindowHint(glfw.OpenGLForwardCompatible, glfw.True)
// make an application window
window, err := glfw.CreateWindow(windowWidth, windowHeight, "Hello", nil, nil)
if err != nil {
panic(err)
}
window.MakeContextCurrent()
// init gl
if err := gl.Init(); err != nil {
panic(err)
}
fmt.Println("OpenGL version", gl.GoStr(gl.GetString(gl.VERSION)))
// create vertex & fragment shader
program, err := newProgram(vertexShader, fragmentShader)
if err != nil {
panic(err)
}
gl.UseProgram(program)
gl.BindFragDataLocation(program, 0, gl.Str("fc\x00"))
points := []float32{
-0.5, -0.5,
0.5, 0.5,
0.5, -0.5,
-0.5, 0.5,
}
vertices := []uint32{
0, 2, 1, 3,
}
// configure the vertex data
var vao uint32
gl.GenVertexArrays(1, &vao)
gl.BindVertexArray(vao)
defer gl.BindVertexArray(0)
var vbo uint32
gl.GenBuffers(1, &vbo)
gl.BindBuffer(gl.ARRAY_BUFFER, vbo)
gl.BufferData(gl.ARRAY_BUFFER, len(points)*4, gl.Ptr(points), gl.STATIC_DRAW)
var ibo uint32
gl.GenBuffers(1, &ibo)
gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, ibo)
gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, len(vertices)*4, gl.Ptr(vertices), gl.STATIC_DRAW)
vertAttrib := uint32(gl.GetAttribLocation(program, gl.Str("pv\x00")))
gl.EnableVertexAttribArray(vertAttrib)
gl.VertexAttribPointer(vertAttrib, 2, gl.FLOAT, false, 2*4, gl.PtrOffset(0))
// global settings
gl.Enable(gl.DEPTH_TEST)
gl.DepthFunc(gl.LESS)
gl.ClearColor(1.0, 1.0, 1.0, 1.0)
for !window.ShouldClose() {
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
gl.UseProgram(program)
gl.BindVertexArray(vao)
gl.DrawElements(gl.LINE_LOOP, 4, gl.UNSIGNED_INT, gl.PtrOffset(0))
window.SwapBuffers()
glfw.PollEvents()
}
}
func Init() error {
if err := gl.Init(); err != nil {
return err
}
log.Printf("OpenGL version: %s", gl.GoStr(gl.GetString(gl.VERSION)))
vs, err := asset.String("shader.vert")
if err != nil {
return err
}
fs, err := asset.String("shader.frag")
if err != nil {
return err
}
program, err := createProgram(vs, fs)
if err != nil {
return err
}
gl.UseProgram(program)
var shaderErr error
uniform := func(name string) int32 {
var loc int32
loc, shaderErr = getUniformLocation(program, name)
return loc
}
projectionViewMatrixUniform = uniform("u_projectionViewMatrix")
modelMatrixUniform = uniform("u_modelMatrix")
normalMatrixUniform = uniform("u_normalMatrix")
ambientLightColorUniform = uniform("u_ambientLightColor")
directionalLightColorUniform = uniform("u_directionalLightColor")
directionalVectorUniform = uniform("u_directionalVector")
textureUniform = uniform("u_texture")
grayscaleUniform = uniform("u_grayscale")
brightnessUniform = uniform("u_brightness")
alphaUniform = uniform("u_alpha")
mixColorUniform = uniform("u_mixColor")
mixAmountUniform = uniform("u_mixAmount")
if shaderErr != nil {
return shaderErr
}
vm := newViewMatrix(cameraPosition, targetPosition, up)
nm := vm.inverse().transpose()
gl.UniformMatrix4fv(normalMatrixUniform, 1, false, &nm[0])
gl.Uniform3fv(ambientLightColorUniform, 1, &ambientLightColor[0])
gl.Uniform3fv(directionalLightColorUniform, 1, &directionalLightColor[0])
gl.Uniform3fv(directionalVectorUniform, 1, &directionalVector[0])
SizeCallback = func(width, height int) {
if winWidth == width && winHeight == height {
return
}
log.Printf("window size changed (%dx%d -> %dx%d)", int(winWidth), int(winHeight), width, height)
gl.Viewport(0, 0, int32(width), int32(height))
// Calculate new perspective projection view matrix.
winWidth, winHeight = width, height
fw, fh := float32(width), float32(height)
aspect := fw / fh
fovRadians := float32(math.Pi) / 3
perspectiveProjectionViewMatrix = vm.mult(newPerspectiveMatrix(fovRadians, aspect, 1, 2000))
// Calculate new ortho projection view matrix.
orthoProjectionViewMatrix = newOrthoMatrix(fw, fh, fw /* use width as depth */)
}
if err := initMeshes(); err != nil {
return err
}
if err := initTextures(); err != nil {
return err
}
gl.Enable(gl.CULL_FACE)
gl.CullFace(gl.BACK)
gl.Enable(gl.DEPTH_TEST)
gl.DepthFunc(gl.LESS)
gl.Enable(gl.BLEND)
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
gl.ClearColor(0, 0, 0, 0)
return nil
}
func InitGL() error {
defer tlog.FuncLog(tlog.Func("InitGL"))
err := gl.Init()
if err != nil {
return err
}
gl.GetError() // cleanup gl error state
version := gl.GoStr(gl.GetString(gl.VERSION))
tlog.Println("OpenGL version", version)
gl.PolygonMode(gl.FRONT_AND_BACK, gl.FILL)
Check()
gl.ReadBuffer(gl.BACK)
Check()
gl.DrawBuffer(gl.BACK)
Check()
gl.FrontFace(gl.CW)
Check()
gl.CullFace(gl.BACK)
Check()
gl.Disable(gl.CULL_FACE)
Check()
gl.ClearColor(1, 1, 0.5, 0)
Check()
gl.ClearDepth(1.0)
Check()
gl.ClearStencil(0)
Check()
gl.Disable(gl.STENCIL_TEST)
Check()
gl.StencilMask(0xFFFFFFFF)
Check()
gl.StencilFunc(gl.EQUAL, 0x00000000, 0x00000001)
Check()
gl.StencilOp(gl.KEEP, gl.KEEP, gl.KEEP)
Check()
gl.Disable(gl.DITHER)
Check()
gl.Enable(gl.DEPTH_TEST)
Check()
gl.DepthFunc(gl.LEQUAL)
Check()
gl.DepthMask(true)
Check()
gl.DepthRange(0., 1.)
Check()
gl.Enable(gl.DEPTH_CLAMP)
Check()
gl.Enable(gl.BLEND)
Check()
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
ForceCheck()
return nil
}
func main() {
// init glfw
if err := glfw.Init(); err != nil {
panic(err)
}
defer glfw.Terminate()
glfw.WindowHint(glfw.Resizable, glfw.False)
glfw.WindowHint(glfw.ContextVersionMajor, 4)
glfw.WindowHint(glfw.ContextVersionMinor, 1)
glfw.WindowHint(glfw.OpenGLProfile, glfw.OpenGLCoreProfile)
glfw.WindowHint(glfw.OpenGLForwardCompatible, glfw.True)
// make an application window
window, err := glfw.CreateWindow(windowWidth, windowHeight, "Transform", nil, nil)
if err != nil {
panic(err)
}
window.MakeContextCurrent()
// init gl
if err := gl.Init(); err != nil {
panic(err)
}
fmt.Println("OpenGL version", gl.GoStr(gl.GetString(gl.VERSION)))
// create vertex & fragment shader
program, err := newProgram(vertexShader, fragmentShader)
if err != nil {
panic(err)
}
gl.UseProgram(program)
projection := mgl32.Perspective(mgl32.DegToRad(45.0), float32(windowWidth)/windowHeight, 0.1, 10.0)
projectionUniform := gl.GetUniformLocation(program, gl.Str("projection\x00"))
gl.UniformMatrix4fv(projectionUniform, 1, false, &projection[0])
camera := mgl32.LookAtV(
mgl32.Vec3{3, 3, 3},
mgl32.Vec3{0, 0, 0},
mgl32.Vec3{0, 1, 0},
)
cameraUniform := gl.GetUniformLocation(program, gl.Str("camera\x00"))
gl.UniformMatrix4fv(cameraUniform, 1, false, &camera[0])
model := mgl32.Ident4()
modelUniform := gl.GetUniformLocation(program, gl.Str("model\x00"))
gl.UniformMatrix4fv(modelUniform, 1, false, &model[0])
gl.BindFragDataLocation(program, 0, gl.Str("vert\x00"))
points := []float32{
-0.9, -0.9, -0.9,
0.9, -0.9, -0.9,
0.9, -0.9, 0.9,
-0.9, -0.9, 0.9,
-0.9, 0.9, -0.9,
0.9, 0.9, -0.9,
0.9, 0.9, 0.9,
-0.9, 0.9, 0.9,
}
vertices := []uint32{
0, 1,
1, 2,
2, 3,
3, 0,
0, 4,
1, 5,
2, 6,
3, 7,
4, 5,
5, 6,
6, 7,
7, 4,
}
// configure the vertex data
var vao uint32
gl.GenVertexArrays(1, &vao)
gl.BindVertexArray(vao)
defer gl.BindVertexArray(0)
var vbo uint32
gl.GenBuffers(1, &vbo)
gl.BindBuffer(gl.ARRAY_BUFFER, vbo)
gl.BufferData(gl.ARRAY_BUFFER, len(points)*4, gl.Ptr(points), gl.STATIC_DRAW)
var ibo uint32
gl.GenBuffers(1, &ibo)
gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, ibo)
gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, len(vertices)*4, gl.Ptr(vertices), gl.STATIC_DRAW)
vertAttrib := uint32(gl.GetAttribLocation(program, gl.Str("vert\x00")))
gl.EnableVertexAttribArray(vertAttrib)
gl.VertexAttribPointer(vertAttrib, 3, gl.FLOAT, false, 3*4, gl.PtrOffset(0))
// global settings
gl.Enable(gl.DEPTH_TEST)
gl.DepthFunc(gl.LESS)
gl.ClearColor(0.0, 0.0, 0.0, 1.0)
angleX := 0.0
angleY := 0.0
angleZ := 0.0
previousTime := glfw.GetTime()
for !window.ShouldClose() {
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
time := glfw.GetTime()
elapsed := time - previousTime
previousTime = time
angleX += math.Sin((elapsed / period) * math.Pi * 2.0)
angleY += math.Sin((elapsed / period) / 6.0 * math.Pi * 2.0)
angleZ += math.Sin((elapsed / period) / 3.0 * math.Pi * 2.0)
model = mgl32.HomogRotate3DY(float32(angleY)).Mul4(mgl32.HomogRotate3DX(float32(angleX))).Mul4(mgl32.HomogRotate3DZ(float32(angleZ)))
gl.UseProgram(program)
gl.UniformMatrix4fv(modelUniform, 1, false, &model[0])
gl.BindVertexArray(vao)
gl.DrawElements(gl.LINES, int32(len(vertices)), gl.UNSIGNED_INT, gl.PtrOffset(0))
window.SwapBuffers()
glfw.PollEvents()
}
}