Ejemplo n.º 1
0
// Creating a RenderObject with a given shaderProgram, texture, and set of
// vertices.
func CreateRenderObject(shaderProgram ShaderProgram, texture Texture, vertices []float32) *RenderObject {
	renderObject := new(RenderObject)

	// Creating the basic information.
	renderObject.shaderProgram = uint32(shaderProgram)
	renderObject.texture = uint32(texture)

	gl.GenVertexArrays(1, &renderObject.vao)
	gl.GenBuffers(1, &renderObject.vbo)
	gl.GenBuffers(1, &renderObject.ebo)

	// Filling the RenderObject with information.
	gl.BindVertexArray(renderObject.vao)
	gl.BindBuffer(gl.ARRAY_BUFFER, renderObject.vbo)
	gl.BufferData(gl.ARRAY_BUFFER, len(vertices)*4, gl.Ptr(vertices), gl.STATIC_DRAW)

	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, renderObject.ebo)
	vertOrder := []uint32{
		0, 1, 2,
		2, 3, 0,
	}
	gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, len(vertOrder)*4, gl.Ptr(vertOrder), gl.STATIC_DRAW)

	// Loading up vertex attributes.
	vertAttrib := uint32(gl.GetAttribLocation(renderObject.shaderProgram, gl.Str("vert\x00")))
	gl.EnableVertexAttribArray(vertAttrib)
	gl.VertexAttribPointer(vertAttrib, 2, gl.FLOAT, false, 4*4, gl.PtrOffset(0))

	// Loading up texture attributes.
	texAttrib := uint32(gl.GetAttribLocation(renderObject.shaderProgram, gl.Str("vertTexCoord\x00")))
	gl.EnableVertexAttribArray(texAttrib)
	gl.VertexAttribPointer(texAttrib, 2, gl.FLOAT, false, 4*4, gl.PtrOffset(2*4))

	return renderObject
}
Ejemplo n.º 2
0
func LoadText(f *Font) (t *Text) {
	t = new(Text)
	t.font = f

	// text hover values
	// "resting state" of a text object is the min scale
	t.ScaleMin = 1.0
	t.ScaleMax = 1.1
	t.SetScale(1)

	// size of glfloat
	glfloat_size := int32(4)

	// stride of the buffered data
	xy_count := int32(2)
	stride := xy_count + int32(2)

	gl.GenVertexArrays(1, &t.vao)
	gl.GenBuffers(1, &t.vbo)
	gl.GenBuffers(1, &t.ebo)

	// vao
	gl.BindVertexArray(t.vao)

	gl.ActiveTexture(gl.TEXTURE0)
	gl.BindTexture(gl.TEXTURE_2D, t.font.textureID)

	// vbo
	// specify the buffer for which the VertexAttribPointer calls apply
	gl.BindBuffer(gl.ARRAY_BUFFER, t.vbo)

	gl.EnableVertexAttribArray(t.font.centeredPosition)
	gl.VertexAttribPointer(
		t.font.centeredPosition,
		2,
		gl.FLOAT,
		false,
		glfloat_size*stride,
		gl.PtrOffset(0),
	)

	gl.EnableVertexAttribArray(t.font.uv)
	gl.VertexAttribPointer(
		t.font.uv,
		2,
		gl.FLOAT,
		false,
		glfloat_size*stride,
		gl.PtrOffset(int(glfloat_size*xy_count)),
	)

	// ebo
	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, t.ebo)

	// i am guessing that order is important here
	gl.BindVertexArray(0)
	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, 0)
	return t
}
Ejemplo n.º 3
0
func CreateSprite(t Texture) (s Sprite, err error) {

	s.texture = t
	s.shader, err = CreateShader(vertexShader, fragmentShader)
	if err != nil {
		return s, err
	}

	gl.GenBuffers(1, &s.ebo)
	gl.GenBuffers(1, &s.vbo)
	gl.GenVertexArrays(1, &s.vao)

	gl.BindVertexArray(s.vao)

	gl.BindBuffer(gl.ARRAY_BUFFER, s.vbo)
	gl.BufferData(gl.ARRAY_BUFFER, len(vertices)*4, gl.Ptr(vertices), gl.STATIC_DRAW)

	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, s.ebo)
	gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, len(indices)*4, gl.Ptr(indices), gl.STATIC_DRAW)

	err = s.shader.SetAttrib("vert", 2, gl.FLOAT, 4*4, 0)
	err = s.shader.SetAttrib("vertTexCoord", 2, gl.FLOAT, 4*4, 2*4)

	gl.BindVertexArray(0)

	return s, err
}
Ejemplo n.º 4
0
func createPlane(x0, y0, x1, y1 float32, verts [12]float32, indexes [6]uint32, uvs [8]float32, normals [12]float32) *Renderable {
	const floatSize = 4
	const uintSize = 4

	r := NewRenderable()
	gl.GenVertexArrays(1, &r.Vao)
	r.FaceCount = 2

	// create a VBO to hold the vertex data
	gl.GenBuffers(1, &r.VertVBO)
	gl.BindBuffer(gl.ARRAY_BUFFER, r.VertVBO)
	gl.BufferData(gl.ARRAY_BUFFER, floatSize*len(verts), gl.Ptr(&verts[0]), gl.STATIC_DRAW)

	// create a VBO to hold the uv data
	gl.GenBuffers(1, &r.UvVBO)
	gl.BindBuffer(gl.ARRAY_BUFFER, r.UvVBO)
	gl.BufferData(gl.ARRAY_BUFFER, floatSize*len(uvs), gl.Ptr(&uvs[0]), gl.STATIC_DRAW)

	// create a VBO to hold the normals data
	gl.GenBuffers(1, &r.NormsVBO)
	gl.BindBuffer(gl.ARRAY_BUFFER, r.NormsVBO)
	gl.BufferData(gl.ARRAY_BUFFER, floatSize*len(normals), gl.Ptr(&normals[0]), gl.STATIC_DRAW)

	// create a VBO to hold the face indexes
	gl.GenBuffers(1, &r.ElementsVBO)
	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, r.ElementsVBO)
	gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, uintSize*len(indexes), gl.Ptr(&indexes[0]), gl.STATIC_DRAW)

	return r
}
Ejemplo n.º 5
0
func (p *Program) createVAO() error {
	gl.GenVertexArrays(1, &p.vao)
	if e := gl.GetError(); e != 0 {
		return fmt.Errorf("ERROR gl.GenVertexArray %X", e)
	}
	gl.BindVertexArray(p.vao)
	if e := gl.GetError(); e != 0 {
		return fmt.Errorf("ERROR array.Bind %X", e)
	}
	return nil
}
Ejemplo n.º 6
0
//CreateVertexArray is a "constructor" of vertex array, hence returns a opengl
//mesh, specifically a cube for testing
func CreateVertexArray() VertexArray {
	var vertexArray VertexArray
	cubeVertices := vertexArray.PosData()
	gl.GenVertexArrays(1, &vertexArray.handleVAO)

	gl.BindVertexArray(vertexArray.handleVAO)

	gl.GenBuffers(1, &vertexArray.handleVBO)
	gl.BindBuffer(gl.ARRAY_BUFFER, vertexArray.handleVBO)
	gl.BufferData(gl.ARRAY_BUFFER, len(cubeVertices)*4, gl.Ptr(cubeVertices), gl.STATIC_DRAW)
	return vertexArray
}
Ejemplo n.º 7
0
func CreateVAO() (array uint32, err error) {
	gl.GenVertexArrays(1, &array)
	if e := gl.GetError(); e != 0 {
		err = fmt.Errorf("ERROR gl.GenVertexArray %X", e)
		return
	}
	gl.BindVertexArray(array)
	if e := gl.GetError(); e != 0 {
		err = fmt.Errorf("ERROR array.Bind %X", e)
		return
	}
	return
}
Ejemplo n.º 8
0
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)

	}

}
Ejemplo n.º 9
0
// Creating a LineReader with an initial list of points.
func NewLineRender(shaderProgram ShaderProgram, color Color, static bool, weight float32, points []Point) *LineRender {
	lr := new(LineRender)

	// Setting the values non-changing values.
	lr.shaderProgram = uint32(shaderProgram)
	lr.color = color
	lr.static = static
	lr.weight = weight

	// Setting up some OpenGL information.
	gl.GenVertexArrays(1, &lr.vao)
	gl.GenBuffers(1, &lr.vbo)
	gl.GenBuffers(1, &lr.ebo)

	lr.UpdatePoints(points)

	return lr
}
Ejemplo n.º 10
0
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}
}
Ejemplo n.º 11
0
func main() {
	vertices, normals := obj.Parse(os.Args[1])

	// initialize GLFW
	if err := glfw.Init(); err != nil {
		panic(err)
	}
	defer glfw.Terminate()

	// set opengl core profile 3.3
	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(640, 480, "GOpenGL", nil, nil)
	if err != nil {
		panic(err)
	}
	window.MakeContextCurrent()

	// initialise OpenGL library
	if err := gl.Init(); err != nil {
		panic(err)
	}

	// link program from shaders
	program, err := newProgram("vertex.glsl", "fragment.glsl")
	if err != nil {
		panic(err)
	}
	gl.UseProgram(program)

	// vertex attribute object holds links between attributes and vbo
	var vao uint32
	gl.GenVertexArrays(1, &vao)
	gl.BindVertexArray(vao)

	// vertex buffer with per-vertex data
	var vbo [2]uint32
	gl.GenBuffers(2, &vbo[0])

	// position data
	gl.BindBuffer(gl.ARRAY_BUFFER, vbo[0])
	gl.BufferData(gl.ARRAY_BUFFER, len(vertices)*4, gl.Ptr(vertices), gl.STATIC_DRAW)

	// set up position attribute with layout of vertices
	posAttrib := uint32(gl.GetAttribLocation(program, gl.Str("position\x00")))
	gl.VertexAttribPointer(posAttrib, 3, gl.FLOAT, false, 3*4, gl.PtrOffset(0))
	gl.EnableVertexAttribArray(posAttrib)

	// normal data
	gl.BindBuffer(gl.ARRAY_BUFFER, vbo[1])
	gl.BufferData(gl.ARRAY_BUFFER, len(normals)*4, gl.Ptr(normals), gl.STATIC_DRAW)

	normAttrib := uint32(gl.GetAttribLocation(program, gl.Str("normal\x00")))
	gl.VertexAttribPointer(normAttrib, 3, gl.FLOAT, false, 3*4, gl.PtrOffset(0))
	gl.EnableVertexAttribArray(normAttrib)

	uniModel := gl.GetUniformLocation(program, gl.Str("model\x00"))
	uniView := gl.GetUniformLocation(program, gl.Str("view\x00"))
	uniProj := gl.GetUniformLocation(program, gl.Str("proj\x00"))

	matView := mgl32.LookAt(2.0, 2.0, 2.0,
		0.0, 0.0, 0.0,
		0.0, 0.0, 1.0)
	gl.UniformMatrix4fv(uniView, 1, false, &matView[0])

	matProj := mgl32.Perspective(mgl32.DegToRad(45.0), 640.0/480.0, 1.0, 10.0)
	gl.UniformMatrix4fv(uniProj, 1, false, &matProj[0])

	uniLightDir := gl.GetUniformLocation(program, gl.Str("lightDir\x00"))
	uniLightCol := gl.GetUniformLocation(program, gl.Str("lightCol\x00"))

	gl.Uniform3f(uniLightDir, -0.5, 0.0, -1.0)
	gl.Uniform3f(uniLightCol, 0.0, 0.5, 0.5)

	startTime := glfw.GetTime()
	gl.Enable(gl.DEPTH_TEST)
	gl.ClearColor(1.0, 1.0, 1.0, 1.0)

	for !window.ShouldClose() {
		// clear buffer
		gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)

		matRot := mgl32.HomogRotate3DZ(float32(glfw.GetTime() - startTime))
		gl.UniformMatrix4fv(uniModel, 1, false, &matRot[0])

		gl.DrawArrays(gl.TRIANGLES, 0, int32(len(vertices)))

		window.SwapBuffers()
		glfw.PollEvents()
	}
}
Ejemplo n.º 12
0
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()
	}
}
Ejemplo n.º 13
0
func createMeshes(objs []*obj) []*mesh {
	var vertexTable []*objVertex
	var normalTable []*objNormal
	var texCoordTable []*objTexCoord

	var vertices []float32
	var normals []float32
	var texCoords []float32

	elementIndexMap := map[objFaceElement]uint16{}
	var nextIndex uint16

	var meshes []*mesh
	var iboNames []uint32

	for _, o := range objs {
		for _, v := range o.vertices {
			vertexTable = append(vertexTable, v)
		}
		for _, n := range o.normals {
			normalTable = append(normalTable, n)
		}
		for _, tc := range o.texCoords {
			texCoordTable = append(texCoordTable, tc)
		}

		var indices []uint16
		for _, f := range o.faces {
			for _, e := range f {
				if _, exists := elementIndexMap[e]; !exists {
					elementIndexMap[e] = nextIndex
					nextIndex++

					v := vertexTable[e.vertexIndex-1]
					vertices = append(vertices, v.x, v.y, v.z)

					n := normalTable[e.normalIndex-1]
					normals = append(normals, n.x, n.y, n.z)

					// Flip the y-axis to convert from OBJ to OpenGL.
					// OpenGL considers the origin to be lower left.
					// OBJ considers the origin to be upper left.
					tc := texCoordTable[e.texCoordIndex-1]
					texCoords = append(texCoords, tc.s, 1.0-tc.t)
				}

				indices = append(indices, elementIndexMap[e])
			}
		}

		meshes = append(meshes, &mesh{
			id:    o.id,
			count: int32(len(indices)),
		})
		iboNames = append(iboNames, createElementArrayBuffer(indices))
	}

	log.Printf("vertices: %d", len(vertexTable))
	log.Printf("normals: %d", len(normalTable))
	log.Printf("texCoords: %d", len(texCoordTable))

	vbo := createArrayBuffer(vertices)
	nbo := createArrayBuffer(normals)
	tbo := createArrayBuffer(texCoords)

	const (
		positionLocation = iota
		normalLocation
		texCoordLocation
	)

	for i, m := range meshes {
		gl.GenVertexArrays(1, &m.vao)
		gl.BindVertexArray(m.vao)

		gl.BindBuffer(gl.ARRAY_BUFFER, vbo)
		gl.EnableVertexAttribArray(positionLocation)
		gl.VertexAttribPointer(positionLocation, 3, gl.FLOAT, false, 0, gl.PtrOffset(0))

		gl.BindBuffer(gl.ARRAY_BUFFER, nbo)
		gl.EnableVertexAttribArray(normalLocation)
		gl.VertexAttribPointer(normalLocation, 3, gl.FLOAT, false, 0, gl.PtrOffset(0))

		gl.BindBuffer(gl.ARRAY_BUFFER, tbo)
		gl.EnableVertexAttribArray(texCoordLocation)
		gl.VertexAttribPointer(texCoordLocation, 2, gl.FLOAT, false, 0, gl.PtrOffset(0))

		gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, iboNames[i])
		gl.BindVertexArray(0)
	}

	return meshes
}
Ejemplo n.º 14
0
func loadBoundingBox(f *Font, X1 Point, X2 Point) (b *BoundingBox, err error) {
	b = new(BoundingBox)
	b.font = f

	// create shader program and define attributes and uniforms
	b.program, err = NewProgram(boxVertexShaderSource, boxFragmentShaderSource)
	if err != nil {
		return b, err
	}

	// ebo, vbo data
	b.vboIndexCount = 4 * 2 // 4 indexes per bounding box (containing 2 position)
	b.eboIndexCount = 6     // each rune requires 6 triangle indices for a quad
	b.vboData = make([]float32, b.vboIndexCount, b.vboIndexCount)
	b.eboData = make([]int32, b.eboIndexCount, b.eboIndexCount)
	b.makeBufferData(X1, X2)
	if f.IsDebug {
		fmt.Printf("bounding %v %v\n", X1, X2)
		fmt.Printf("bounding vbo data\n%v\n", b.vboData)
		fmt.Printf("bounding ebo data\n%v\n", b.eboData)
	}

	// attributes
	b.centeredPosition = uint32(gl.GetAttribLocation(b.program, gl.Str("centered_position\x00")))

	// uniforms
	b.finalPositionUniform = gl.GetUniformLocation(b.program, gl.Str("final_position\x00"))
	b.orthographicMatrixUniform = gl.GetUniformLocation(b.program, gl.Str("orthographic_matrix\x00"))

	// size of glfloat
	glfloatSize := int32(4)

	gl.GenVertexArrays(1, &b.vao)
	gl.GenBuffers(1, &b.vbo)
	gl.GenBuffers(1, &b.ebo)

	// vao
	gl.BindVertexArray(b.vao)

	// vbo
	// specify the buffer for which the VertexAttribPointer calls apply
	gl.BindBuffer(gl.ARRAY_BUFFER, b.vbo)

	gl.EnableVertexAttribArray(b.centeredPosition)
	gl.VertexAttribPointer(
		b.centeredPosition,
		2,
		gl.FLOAT,
		false,
		0,
		gl.PtrOffset(0),
	)
	gl.BufferData(gl.ARRAY_BUFFER, int(glfloatSize)*b.vboIndexCount, gl.Ptr(b.vboData), gl.DYNAMIC_DRAW)

	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, b.ebo)
	gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, int(glfloatSize)*b.eboIndexCount, gl.Ptr(b.eboData), gl.DYNAMIC_DRAW)
	gl.BindVertexArray(0)

	// not necesssary, but i just want to better understand using vertex arrays
	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, 0)

	return b, nil
}
Ejemplo n.º 15
0
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()
	}
}
Ejemplo n.º 16
0
// CreateSphere generates a 3d uv-sphere with the given radius and returns a Renderable.
func CreateSphere(radius float32, rings int, sectors int) *Renderable {
	// nothing to create
	if rings < 2 || sectors < 2 {
		return nil
	}

	const piDiv2 = math.Pi / 2.0

	verts := make([]float32, 0, rings*sectors)
	indexes := make([]uint32, 0, rings*sectors)
	uvs := make([]float32, 0, rings*sectors)
	normals := make([]float32, 0, rings*sectors)

	R := float64(1.0 / float32(rings-1))
	S := float64(1.0 / float32(sectors-1))

	for ri := 0; ri < int(rings); ri++ {
		for si := 0; si < int(sectors); si++ {
			y := float32(math.Sin(-piDiv2 + math.Pi*float64(ri)*R))
			x := float32(math.Cos(2.0*math.Pi*float64(si)*S) * math.Sin(math.Pi*float64(ri)*R))
			z := float32(math.Sin(2.0*math.Pi*float64(si)*S) * math.Sin(math.Pi*float64(ri)*R))

			uvs = append(uvs, float32(si)*float32(S))
			uvs = append(uvs, float32(ri)*float32(R))

			verts = append(verts, x*radius)
			verts = append(verts, y*radius)
			verts = append(verts, z*radius)

			normals = append(normals, x)
			normals = append(normals, y)
			normals = append(normals, z)

			currentRow := ri * sectors
			nextRow := (ri + 1) * sectors

			indexes = append(indexes, uint32(currentRow+si))
			indexes = append(indexes, uint32(nextRow+si))
			indexes = append(indexes, uint32(nextRow+si+1))

			indexes = append(indexes, uint32(currentRow+si))
			indexes = append(indexes, uint32(nextRow+si+1))
			indexes = append(indexes, uint32(currentRow+si+1))
		}
	}

	r := NewRenderable()
	gl.GenVertexArrays(1, &r.Vao)
	r.FaceCount = rings * sectors * 2

	const floatSize = 4
	const uintSize = 4

	// create a VBO to hold the vertex data
	gl.GenBuffers(1, &r.VertVBO)
	gl.BindBuffer(gl.ARRAY_BUFFER, r.VertVBO)
	gl.BufferData(gl.ARRAY_BUFFER, floatSize*len(verts), gl.Ptr(&verts[0]), gl.STATIC_DRAW)

	// create a VBO to hold the uv data
	gl.GenBuffers(1, &r.UvVBO)
	gl.BindBuffer(gl.ARRAY_BUFFER, r.UvVBO)
	gl.BufferData(gl.ARRAY_BUFFER, floatSize*len(uvs), gl.Ptr(&uvs[0]), gl.STATIC_DRAW)

	// create a VBO to hold the normals data
	gl.GenBuffers(1, &r.NormsVBO)
	gl.BindBuffer(gl.ARRAY_BUFFER, r.NormsVBO)
	gl.BufferData(gl.ARRAY_BUFFER, floatSize*len(normals), gl.Ptr(&normals[0]), gl.STATIC_DRAW)

	// create a VBO to hold the face indexes
	gl.GenBuffers(1, &r.ElementsVBO)
	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, r.ElementsVBO)
	gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, uintSize*len(indexes), gl.Ptr(&indexes[0]), gl.STATIC_DRAW)

	return r
}
Ejemplo n.º 17
0
// CreateCube makes a new Renderable object with the specified dimensions for the cube.
func CreateCube(xmin, ymin, zmin, xmax, ymax, zmax float32) *Renderable {
	/* Cube vertices are layed out like this:

	  +--------+           6          5
	/ |       /|
	+--------+ |        1          0        +Y
	| |      | |                            |___ +X
	| +------|-+           7          4    /
	|/       |/                           +Z
	+--------+          2          3

	*/

	verts := [...]float32{
		xmax, ymax, zmax, xmin, ymax, zmax, xmin, ymin, zmax, xmax, ymin, zmax, // v0,v1,v2,v3 (front)
		xmax, ymax, zmin, xmax, ymax, zmax, xmax, ymin, zmax, xmax, ymin, zmin, // v5,v0,v3,v4 (right)
		xmax, ymax, zmin, xmin, ymax, zmin, xmin, ymax, zmax, xmax, ymax, zmax, // v5,v6,v1,v0 (top)
		xmin, ymax, zmax, xmin, ymax, zmin, xmin, ymin, zmin, xmin, ymin, zmax, // v1,v6,v7,v2 (left)
		xmax, ymin, zmax, xmin, ymin, zmax, xmin, ymin, zmin, xmax, ymin, zmin, // v3,v2,v7,v4 (bottom)
		xmin, ymax, zmin, xmax, ymax, zmin, xmax, ymin, zmin, xmin, ymin, zmin, // v6,v5,v4,v7 (back)
	}
	indexes := [...]uint32{
		0, 1, 2, 2, 3, 0,
		4, 5, 6, 6, 7, 4,
		8, 9, 10, 10, 11, 8,
		12, 13, 14, 14, 15, 12,
		16, 17, 18, 18, 19, 16,
		20, 21, 22, 22, 23, 20,
	}
	uvs := [...]float32{
		1.0, 1.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0,
		1.0, 1.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0,
		1.0, 1.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0,
		1.0, 1.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0,
		1.0, 1.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0,
		1.0, 1.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0,
	}
	normals := [...]float32{
		0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, // v0,v1,v2,v3 (front)
		1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, // v5,v0,v3,v4 (right)
		0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, // v5,v6,v1,v0 (top)
		-1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, // v1,v6,v7,v2 (left)
		0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, 0, // v3,v2,v7,v4 (bottom)
		0, 0, -1, 0, 0, -1, 0, 0, -1, 0, 0, -1, // v6,v5,v4,v7 (back)
	}

	r := NewRenderable()
	gl.GenVertexArrays(1, &r.Vao)
	r.FaceCount = 12

	const floatSize = 4
	const uintSize = 4

	// create a VBO to hold the vertex data
	gl.GenBuffers(1, &r.VertVBO)
	gl.BindBuffer(gl.ARRAY_BUFFER, r.VertVBO)
	gl.BufferData(gl.ARRAY_BUFFER, floatSize*len(verts), gl.Ptr(&verts[0]), gl.STATIC_DRAW)

	// create a VBO to hold the uv data
	gl.GenBuffers(1, &r.UvVBO)
	gl.BindBuffer(gl.ARRAY_BUFFER, r.UvVBO)
	gl.BufferData(gl.ARRAY_BUFFER, floatSize*len(uvs), gl.Ptr(&uvs[0]), gl.STATIC_DRAW)

	// create a VBO to hold the normals data
	gl.GenBuffers(1, &r.NormsVBO)
	gl.BindBuffer(gl.ARRAY_BUFFER, r.NormsVBO)
	gl.BufferData(gl.ARRAY_BUFFER, floatSize*len(normals), gl.Ptr(&normals[0]), gl.STATIC_DRAW)

	// create a VBO to hold the face indexes
	gl.GenBuffers(1, &r.ElementsVBO)
	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, r.ElementsVBO)
	gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, uintSize*len(indexes), gl.Ptr(&indexes[0]), gl.STATIC_DRAW)

	return r
}
Ejemplo n.º 18
0
// bindString generates all of the vertex buffers and vertex arrays for a single constant line of
// text.  No error checking is done.
func (d *Dictionary) bindString(str string) strData {
	var data strData
	gl.GenVertexArrays(1, &data.varrays[0])
	gl.BindVertexArray(data.varrays[0])
	gl.GenBuffers(2, &data.vbuffers[0])

	var positions, texcoords []float32

	var pen pos
	var prev rune
	for _, r := range str {
		ri := d.Runes[r]

		var scale float32 = 1.0 / float32(d.GlyphMax.Dy())

		var posMin, posMax pos
		posMin.x = pen.x + float32(ri.GlyphBounds.Min.X)*scale
		posMin.y = pen.y + float32(ri.GlyphBounds.Min.Y)*scale
		posMax.x = pen.x + float32(ri.GlyphBounds.Max.X)*scale
		posMax.y = pen.y + float32(ri.GlyphBounds.Max.Y)*scale

		var texMin, texMax pos
		texMin.x = float32(ri.PixBounds.Min.X) / float32(d.Dx)
		texMin.y = float32(ri.PixBounds.Min.Y) / float32(d.Dy)
		texMax.x = float32(ri.PixBounds.Max.X) / float32(d.Dx)
		texMax.y = float32(ri.PixBounds.Max.Y) / float32(d.Dy)
		pen.x += float32(ri.AdvanceWidth) * scale
		pen.x += float32(d.Kerning[RunePair{prev, r}]) * scale
		// pen.x -= float32(d.Kerning[RunePair{prev, r}]) * scale

		positions = append(positions, posMin.x) // lower left
		positions = append(positions, posMin.y)
		positions = append(positions, posMin.x) // upper left
		positions = append(positions, posMax.y)
		positions = append(positions, posMax.x) // upper right
		positions = append(positions, posMax.y)
		positions = append(positions, posMin.x) // lower left
		positions = append(positions, posMin.y)
		positions = append(positions, posMax.x) // upper right
		positions = append(positions, posMax.y)
		positions = append(positions, posMax.x) // lower right
		positions = append(positions, posMin.y)
		texcoords = append(texcoords, texMin.x) // lower left
		texcoords = append(texcoords, texMax.y)
		texcoords = append(texcoords, texMin.x) // upper left
		texcoords = append(texcoords, texMin.y)
		texcoords = append(texcoords, texMax.x) // upper right
		texcoords = append(texcoords, texMin.y)
		texcoords = append(texcoords, texMin.x) // lower left
		texcoords = append(texcoords, texMax.y)
		texcoords = append(texcoords, texMax.x) // upper right
		texcoords = append(texcoords, texMin.y)
		texcoords = append(texcoords, texMax.x) // lower right
		texcoords = append(texcoords, texMax.y)

		prev = r
	}
	data.count = int32(len(positions))
	gl.BindBuffer(gl.ARRAY_BUFFER, data.vbuffers[0])
	gl.BufferData(gl.ARRAY_BUFFER, len(positions)*int(unsafe.Sizeof(positions[0])), gl.Ptr(&positions[0]), gl.STATIC_DRAW)
	location, _ := render.GetAttribLocation("glop.font", "position")
	gl.EnableVertexAttribArray(uint32(location))
	gl.VertexAttribPointer(uint32(location), 2, gl.FLOAT, false, 0, gl.PtrOffset(0))

	gl.BindBuffer(gl.ARRAY_BUFFER, data.vbuffers[1])
	gl.BufferData(gl.ARRAY_BUFFER, len(texcoords)*int(unsafe.Sizeof(texcoords[0])), gl.Ptr(&texcoords[0]), gl.STATIC_DRAW)
	location, _ = render.GetAttribLocation("glop.font", "texCoord")
	gl.EnableVertexAttribArray(uint32(location))
	gl.VertexAttribPointer(uint32(location), 2, gl.FLOAT, false, 0, gl.PtrOffset(0))

	return data
}