func setupUniforms(shader *renderer.Shader) {
for name, uniform := range shader.Uniforms {
uniformLocation := gl.GetUniformLocation(shader.Program, gl.Str(name+"\x00"))
switch t := uniform.(type) {
case bool:
if t {
gl.Uniform1i(uniformLocation, 1)
} else {
gl.Uniform1i(uniformLocation, 0)
}
case float32:
gl.Uniform1f(uniformLocation, t)
case float64:
gl.Uniform1f(uniformLocation, float32(t))
case int32:
gl.Uniform1i(uniformLocation, t)
case int:
gl.Uniform1i(uniformLocation, int32(t))
case mgl32.Vec2:
gl.Uniform2f(uniformLocation, t[0], t[1])
case mgl32.Vec3:
gl.Uniform3f(uniformLocation, t[0], t[1], t[2])
case mgl32.Vec4:
gl.Uniform4f(uniformLocation, t[0], t[1], t[2], t[3])
case mgl32.Mat4:
gl.UniformMatrix4fv(uniformLocation, 1, false, &t[0])
case []float32:
gl.Uniform4fv(uniformLocation, (int32)(len(t)), &t[0])
case []int32:
gl.Uniform4iv(uniformLocation, (int32)(len(t)), &t[0])
default:
fmt.Printf("unexpected type for shader uniform: %T\n", t)
}
}
}
func programLoop(window *win.Window) error {
// the linked shader program determines how the data will be rendered
vertShader, err := gfx.NewShaderFromFile("shaders/phong.vert", gl.VERTEX_SHADER)
if err != nil {
return err
}
fragShader, err := gfx.NewShaderFromFile("shaders/phong.frag", gl.FRAGMENT_SHADER)
if err != nil {
return err
}
program, err := gfx.NewProgram(vertShader, fragShader)
if err != nil {
return err
}
defer program.Delete()
lightFragShader, err := gfx.NewShaderFromFile("shaders/light.frag", gl.FRAGMENT_SHADER)
if err != nil {
return err
}
// special shader program so that lights themselves are not affected by lighting
lightProgram, err := gfx.NewProgram(vertShader, lightFragShader)
if err != nil {
return err
}
VAO := createVAO(cubeVertices, nil)
lightVAO := createVAO(cubeVertices, nil)
// ensure that triangles that are "behind" others do not draw over top of them
gl.Enable(gl.DEPTH_TEST)
camera := cam.NewFpsCamera(mgl32.Vec3{0, 0, 3}, mgl32.Vec3{0, 1, 0}, -90, 0, window.InputManager())
for !window.ShouldClose() {
// swaps in last buffer, polls for window events, and generally sets up for a new render frame
window.StartFrame()
// update camera position and direction from input evevnts
camera.Update(window.SinceLastFrame())
// background color
gl.ClearColor(0, 0, 0, 1.0)
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT) // depth buffer needed for DEPTH_TEST
// cube rotation matrices
rotateX := (mgl32.Rotate3DX(mgl32.DegToRad(-45 * float32(glfw.GetTime()))))
rotateY := (mgl32.Rotate3DY(mgl32.DegToRad(-45 * float32(glfw.GetTime()))))
rotateZ := (mgl32.Rotate3DZ(mgl32.DegToRad(-45 * float32(glfw.GetTime()))))
// creates perspective
fov := float32(60.0)
projectTransform := mgl32.Perspective(mgl32.DegToRad(fov),
float32(window.Width())/float32(window.Height()),
0.1,
100.0)
camTransform := camera.GetTransform()
lightPos := mgl32.Vec3{0.6, 1, 0.1}
lightTransform := mgl32.Translate3D(lightPos.X(), lightPos.Y(), lightPos.Z()).Mul4(
mgl32.Scale3D(0.2, 0.2, 0.2))
program.Use()
gl.UniformMatrix4fv(program.GetUniformLocation("view"), 1, false, &camTransform[0])
gl.UniformMatrix4fv(program.GetUniformLocation("project"), 1, false,
&projectTransform[0])
gl.BindVertexArray(VAO)
// draw each cube after all coordinate system transforms are bound
// obj is colored, light is white
gl.Uniform3f(program.GetUniformLocation("material.ambient"), 1.0, 0.5, 0.31)
gl.Uniform3f(program.GetUniformLocation("material.diffuse"), 1.0, 0.5, 0.31)
gl.Uniform3f(program.GetUniformLocation("material.specular"), 0.5, 0.5, 0.5)
gl.Uniform1f(program.GetUniformLocation("material.shininess"), 32.0)
lightColor := mgl32.Vec3{
float32(math.Sin(glfw.GetTime() * 1)),
float32(math.Sin(glfw.GetTime() * 0.35)),
float32(math.Sin(glfw.GetTime() * 0.65)),
}
diffuseColor := mgl32.Vec3{
0.5 * lightColor[0],
0.5 * lightColor[1],
0.5 * lightColor[2],
}
ambientColor := mgl32.Vec3{
0.2 * lightColor[0],
0.2 * lightColor[1],
0.2 * lightColor[2],
}
gl.Uniform3f(program.GetUniformLocation("light.ambient"),
ambientColor[0], ambientColor[1], ambientColor[2])
gl.Uniform3f(program.GetUniformLocation("light.diffuse"),
diffuseColor[0], diffuseColor[1], diffuseColor[2])
gl.Uniform3f(program.GetUniformLocation("light.specular"), 1.0, 1.0, 1.0)
gl.Uniform3f(program.GetUniformLocation("light.position"), lightPos.X(), lightPos.Y(), lightPos.Z())
for _, pos := range cubePositions {
// turn the cubes into rectangular prisms for more fun
worldTranslate := mgl32.Translate3D(pos[0], pos[1], pos[2])
worldTransform := worldTranslate.Mul4(
rotateX.Mul3(rotateY).Mul3(rotateZ).Mat4(),
)
gl.UniformMatrix4fv(program.GetUniformLocation("model"), 1, false,
&worldTransform[0])
gl.DrawArrays(gl.TRIANGLES, 0, 36)
}
gl.BindVertexArray(0)
// Draw the light obj after the other boxes using its separate shader program
// this means that we must re-bind any uniforms
lightProgram.Use()
gl.BindVertexArray(lightVAO)
gl.UniformMatrix4fv(lightProgram.GetUniformLocation("model"), 1, false, &lightTransform[0])
gl.UniformMatrix4fv(lightProgram.GetUniformLocation("view"), 1, false, &camTransform[0])
gl.UniformMatrix4fv(lightProgram.GetUniformLocation("project"), 1, false, &projectTransform[0])
gl.DrawArrays(gl.TRIANGLES, 0, 36)
gl.BindVertexArray(0)
// end of draw loop
}
return nil
}