Example #1
0
func display() {
	// Clear the background as white
	gl.ClearColor(1.0, 1.0, 1.0, 1.0)
	gl.Clear(gl.COLOR_BUFFER_BIT)

	// Use the GLSL program
	gl.UseProgram(program)

	gl.BindBuffer(gl.ARRAY_BUFFER, vboTriangle)
	gl.EnableVertexAttribArray(attributeCoord2d)

	// Describe our vertices array to OpenGL (it can't guess its format automatically)
	gl.VertexAttribPointer(attributeCoord2d, 2, gl.FLOAT, gl.FALSE, 0, gl.Pointer(nil))

	gl.EnableVertexAttribArray(attributeColor)
	gl.BindBuffer(gl.ARRAY_BUFFER, vboTriangleColors)
	gl.VertexAttribPointer(attributeColor, 3, gl.FLOAT, gl.FALSE, 0, gl.Pointer(nil))

	// Push each element in buffer_vertices to the vertex shader
	gl.DrawArrays(gl.TRIANGLES, 0, 3)

	gl.DisableVertexAttribArray(attributeCoord2d)
	gl.DisableVertexAttribArray(attributeColor)
	gl.BindBuffer(gl.ARRAY_BUFFER, 0) // Unbind

	// Display the result
	glfw.SwapBuffers()
}
Example #2
0
func initResources() {
	var err error
	// Load shaders
	vs, err = createShader("triangle.v.glsl", VertexShaderType)
	if err != nil {
		fmt.Printf("Shader: %s\n", err)
		return
	}
	fs, err = createShader("triangle.f.glsl", FragmentShaderType)
	if err != nil {
		fmt.Printf("Shader: %s\n", err)
		return
	}

	// Create GLSL program with loaded shaders
	var compileOk gl.Int
	program = gl.CreateProgram()
	gl.AttachShader(program, vs)
	gl.AttachShader(program, fs)
	gl.LinkProgram(program)
	gl.GetProgramiv(program, gl.LINK_STATUS, &compileOk)
	if compileOk == 0 {
		fmt.Printf("Error in program.\n")
	}

	// Generate a buffer for the VertexBufferObject
	gl.GenBuffers(1, &vboTriangle)
	gl.BindBuffer(gl.ARRAY_BUFFER, vboTriangle)
	// Submit the vertices of the triangle to the graphic card
	gl.BufferData(gl.ARRAY_BUFFER, gl.Sizeiptr(len(triangleVertices)*4), gl.Pointer(&triangleVertices[0]), gl.STATIC_DRAW)
	// Unset the active buffer
	gl.BindBuffer(gl.ARRAY_BUFFER, 0)

	// Generate a buffer for the Color-VBO
	gl.GenBuffers(1, &vboTriangleColors)
	gl.BindBuffer(gl.ARRAY_BUFFER, vboTriangleColors)
	gl.BufferData(gl.ARRAY_BUFFER, gl.Sizeiptr(len(triangleColors)*4), gl.Pointer(&triangleColors[0]), gl.STATIC_DRAW)
	gl.BindBuffer(gl.ARRAY_BUFFER, 0)

	// Get the attribute location from the GLSL program (here from the vertex shader)
	attributeName := gl.GLString("coord2d")
	defer gl.GLStringFree(attributeName)
	attributeTemp := gl.GetAttribLocation(program, attributeName)
	if attributeTemp == -1 {
		fmt.Printf("Could not bind attribute %s\n", gl.GoString(attributeName))
	}
	attributeCoord2d = gl.Uint(attributeTemp)

	attributeName = gl.GLString("v_color")
	defer gl.GLStringFree(attributeName)
	attributeTemp = gl.GetAttribLocation(program, attributeName)
	if attributeTemp == -1 {
		fmt.Printf("Could not bind attribute %s\n", gl.GoString(attributeName))
	}
	attributeColor = gl.Uint(attributeTemp)
}
Example #3
0
func (buffer *Buffer) Unbind() {
	bound := buffer.bound()
	if *bound == buffer {
		gl33.BindBuffer(buffer.Target, 0)
		*bound = nil
	}
}
Example #4
0
func (buffer *Buffer) Bind() {
	bound := buffer.bound()
	if *bound != buffer {
		gl33.BindBuffer(buffer.Target, buffer.Id)
		*bound = buffer
	}
}
Example #5
0
func (vbo *VertexBufferObject) Unbind() {
	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
}
Example #6
0
func (vbo *VertexBufferObject) Bind() {
	gl.BindBuffer(gl.ARRAY_BUFFER, vbo.id)
}
Example #7
0
func (vbo *VertexBufferObject) BufferData(data []float32) {
	gl.BindBuffer(gl.ARRAY_BUFFER, vbo.id)
	gl.BufferData(gl.ARRAY_BUFFER, gl.Sizeiptr(len(data)*4), gl.Pointer(&data[0]), gl.STATIC_DRAW)
	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
}
Example #8
0
func main() {
	var window *sdl.Window
	var context sdl.GLContext
	var event sdl.Event
	var running bool
	var err error
	runtime.LockOSThread()
	if err = sdl.Init(sdl.INIT_EVERYTHING); err != nil {
		panic(err)
	}
	defer sdl.Quit()
	window, err = sdl.CreateWindow(winTitle, sdl.WINDOWPOS_UNDEFINED,
		sdl.WINDOWPOS_UNDEFINED,
		winWidth, winHeight, sdl.WINDOW_OPENGL)
	if err != nil {
		panic(err)
	}
	defer window.Destroy()
	context, err = sdl.GL_CreateContext(window)
	if err != nil {
		panic(err)
	}
	defer sdl.GL_DeleteContext(context)

	gl.Init()
	gl.Viewport(0, 0, gl.Sizei(winWidth), gl.Sizei(winHeight))
	// OPENGL FLAGS
	gl.ClearColor(0.0, 0.1, 0.0, 1.0)
	gl.Enable(gl.DEPTH_TEST)
	gl.DepthFunc(gl.LESS)
	gl.Enable(gl.BLEND)
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)

	// VERTEX BUFFER
	var vertexbuffer gl.Uint
	gl.GenBuffers(1, &vertexbuffer)
	gl.BindBuffer(gl.ARRAY_BUFFER, vertexbuffer)
	gl.BufferData(gl.ARRAY_BUFFER, gl.Sizeiptr(len(triangle_vertices)*4), gl.Pointer(&triangle_vertices[0]), gl.STATIC_DRAW)

	// COLOUR BUFFER
	var colourbuffer gl.Uint
	gl.GenBuffers(1, &colourbuffer)
	gl.BindBuffer(gl.ARRAY_BUFFER, colourbuffer)
	gl.BufferData(gl.ARRAY_BUFFER, gl.Sizeiptr(len(triangle_colours)*4), gl.Pointer(&triangle_colours[0]), gl.STATIC_DRAW)

	// GUESS WHAT
	program := createprogram()

	// VERTEX ARRAY
	var VertexArrayID gl.Uint
	gl.GenVertexArrays(1, &VertexArrayID)
	gl.BindVertexArray(VertexArrayID)
	gl.EnableVertexAttribArray(0)
	gl.BindBuffer(gl.ARRAY_BUFFER, vertexbuffer)
	gl.VertexAttribPointer(0, 3, gl.FLOAT, gl.FALSE, 0, nil)

	// VERTEX ARRAY HOOK COLOURS
	gl.EnableVertexAttribArray(1)
	gl.BindBuffer(gl.ARRAY_BUFFER, colourbuffer)
	gl.VertexAttribPointer(1, 3, gl.FLOAT, gl.FALSE, 0, nil)

	//UNIFORM HOOK
	unistring := gl.GLString("scaleMove")
	UniScale = gl.GetUniformLocation(program, unistring)
	fmt.Printf("Uniform Link: %v\n", UniScale+1)

	gl.UseProgram(program)

	running = true
	for running {
		for event = sdl.PollEvent(); event != nil; event =
			sdl.PollEvent() {
			switch t := event.(type) {
			case *sdl.QuitEvent:
				running = false
			case *sdl.MouseMotionEvent:

				xrot = float32(t.Y) / 2
				yrot = float32(t.X) / 2
				fmt.Printf("[%dms]MouseMotion\tid:%d\tx:%d\ty:%d\txrel:%d\tyrel:%d\n", t.Timestamp, t.Which, t.X, t.Y, t.XRel, t.YRel)
			}
		}
		drawgl()
		sdl.GL_SwapWindow(window)
	}
}