// NewBasicHighlighter returns a new instance of BasicHighlighter.
func NewBasicHighlighter(gl opengl.OpenGl, color [4]float32) *BasicHighlighter {
vertexShader, err1 := opengl.CompileNewShader(gl, opengl.VERTEX_SHADER, basicHighlighterVertexShaderSource)
defer gl.DeleteShader(vertexShader)
fragmentShader, err2 := opengl.CompileNewShader(gl, opengl.FRAGMENT_SHADER, basicHighlighterFragmentShaderSource)
defer gl.DeleteShader(fragmentShader)
program, _ := opengl.LinkNewProgram(gl, vertexShader, fragmentShader)
if err1 != nil {
fmt.Fprintf(os.Stderr, "Failed to compile shader 1:\n", err1)
}
if err2 != nil {
fmt.Fprintf(os.Stderr, "Failed to compile shader 2:\n", err2)
}
highlighter := &BasicHighlighter{
gl: gl,
program: program,
vertexArrayObject: gl.GenVertexArrays(1)[0],
vertexPositionBuffer: gl.GenBuffers(1)[0],
vertexPositionAttrib: gl.GetAttribLocation(program, "vertexPosition"),
modelMatrixUniform: gl.GetUniformLocation(program, "modelMatrix"),
viewMatrixUniform: gl.GetUniformLocation(program, "viewMatrix"),
projectionMatrixUniform: gl.GetUniformLocation(program, "projectionMatrix"),
inColorUniform: gl.GetUniformLocation(program, "inColor")}
highlighter.withShader(func() {
gl.BindBuffer(opengl.ARRAY_BUFFER, highlighter.vertexPositionBuffer)
half := float32(0.5)
var vertices = []float32{
-half, -half, 0.0,
half, -half, 0.0,
half, half, 0.0,
half, half, 0.0,
-half, half, 0.0,
-half, -half, 0.0}
gl.BufferData(opengl.ARRAY_BUFFER, len(vertices)*4, vertices, opengl.STATIC_DRAW)
gl.Uniform4fv(highlighter.inColorUniform, &color)
})
return highlighter
}