func drawScene() {
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
gl.LoadIdentity() // 重置当前矩阵
texture.Bind(gl.TEXTURE_2D)
var x_m, y_m, z_m, u_m, v_m float32
xtrans := -xpos
ztrans := -zpos
ytrans := -walkbias - 0.25
sceneroty := 360.0 - yrot
var numtriangles int
gl.Rotatef(lookupdown, 1.0, 0, 0)
gl.Rotatef(sceneroty, 0, 1.0, 0)
gl.Translatef(xtrans, ytrans, ztrans)
numtriangles = sector1.numtriangles
// Process Each Triangle
for loop_m := 0; loop_m < numtriangles; loop_m++ {
gl.Begin(gl.TRIANGLES)
gl.Normal3f(0.0, 0.0, 1.0)
x_m = sector1.triangles[loop_m].vertex[0].x
y_m = sector1.triangles[loop_m].vertex[0].y
z_m = sector1.triangles[loop_m].vertex[0].z
u_m = sector1.triangles[loop_m].vertex[0].u
v_m = sector1.triangles[loop_m].vertex[0].v
gl.TexCoord2f(u_m, v_m)
gl.Vertex3f(x_m, y_m, z_m)
x_m = sector1.triangles[loop_m].vertex[1].x
y_m = sector1.triangles[loop_m].vertex[1].y
z_m = sector1.triangles[loop_m].vertex[1].z
u_m = sector1.triangles[loop_m].vertex[1].u
v_m = sector1.triangles[loop_m].vertex[1].v
gl.TexCoord2f(u_m, v_m)
gl.Vertex3f(x_m, y_m, z_m)
x_m = sector1.triangles[loop_m].vertex[2].x
y_m = sector1.triangles[loop_m].vertex[2].y
z_m = sector1.triangles[loop_m].vertex[2].z
u_m = sector1.triangles[loop_m].vertex[2].u
v_m = sector1.triangles[loop_m].vertex[2].v
gl.TexCoord2f(u_m, v_m)
gl.Vertex3f(x_m, y_m, z_m)
gl.End()
}
}
// normal defines surface normals.
// Used in classic render mode.
func (a *Attr) normal(i int) {
if a.size != 3 {
return
}
i *= a.size
switch v := a.data.(type) {
case []int8:
gl.Normal3b(v[i], v[i+1], v[i+2])
case []int16:
gl.Normal3s(v[i], v[i+1], v[i+2])
case []int32:
gl.Normal3i(int(v[i]), int(v[i+1]), int(v[i+2]))
case []float32:
gl.Normal3f(v[i], v[i+1], v[i+2])
case []float64:
gl.Normal3d(v[i], v[i+1], v[i+2])
}
}
func drawScene() {
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT) //清除屏幕和深度缓存
gl.LoadIdentity() //重置当前的模型观察矩阵
gl.Translatef(0, 0, z) //移入/移出屏幕 z 个单位
gl.Rotatef(rotation[0], 1, 0, 0) //绕X轴旋转
gl.Rotatef(rotation[1], 0, 1, 0) //绕Y轴旋转
rotation[0] += speed[0]
rotation[1] += speed[1]
textures[filter].Bind(gl.TEXTURE_2D) //绑定的纹理
/*
Normal就是法线的意思，所谓法线是指经过面(多边形）上的一点且垂直于这个面(多边形)的直线。
使用光源的时候必须指定一条法线。法线告诉OpenGL这个多边形的朝向，并指明多边形的正面和背面。
如果没有指定法线，什么怪事情都可能发生：不该照亮的面被照亮了，多边形的背面也被照亮....。对了，法线应该指向多边形的外侧。
看着木箱的前面您会注意到法线与Z轴正向同向。这意味着法线正指向观察者－您自己。这正是我们所希望的。
对于木箱的背面，也正如我们所要的，法线背对着观察者。
如果立方体沿着X或Y轴转个180度的话，前侧面的法线仍然朝着观察者，背面的法线也还是背对着观察者。
换句话说，不管是哪个面，只要它朝着观察者这个面的法线就指向观察者。由于光源紧邻观察者，任何时候法线对着观察者时，这个面就会被照亮。
并且法线越朝着光源，就显得越亮一些。如果您把观察点放到立方体内部，你就会法线里面一片漆黑。因为法线是向外指的。
如果立方体内部没有光源的话，当然是一片漆黑。
*/
gl.Begin(gl.QUADS)
// Front Face 前面
gl.Normal3f(0, 0, 1) // Normal Pointing Towards Viewer 法线指向观察者
gl.TexCoord2f(0, 0)
gl.Vertex3f(-1, -1, 1) // Point 1 (Front)
gl.TexCoord2f(1, 0)
gl.Vertex3f(1, -1, 1) // Point 2 (Front)
gl.TexCoord2f(1, 1)
gl.Vertex3f(1, 1, 1) // Point 3 (Front)
gl.TexCoord2f(0, 1)
gl.Vertex3f(-1, 1, 1) // Point 4 (Front)
// Back Face 后面
gl.Normal3f(0, 0, -1) // Normal Pointing Away From Viewer 法线背向观察者
gl.TexCoord2f(1, 0)
gl.Vertex3f(-1, -1, -1) // Point 1 (Back)
gl.TexCoord2f(1, 1)
gl.Vertex3f(-1, 1, -1) // Point 2 (Back)
gl.TexCoord2f(0, 1)
gl.Vertex3f(1, 1, -1) // Point 3 (Back)
gl.TexCoord2f(0, 0)
gl.Vertex3f(1, -1, -1) // Point 4 (Back)
// Top Face 顶面
gl.Normal3f(0, 1, 0) // Normal Pointing Up 法线向上
gl.TexCoord2f(0, 1)
gl.Vertex3f(-1, 1, -1) // Point 1 (Top)
gl.TexCoord2f(0, 0)
gl.Vertex3f(-1, 1, 1) // Point 2 (Top)
gl.TexCoord2f(1, 0)
gl.Vertex3f(1, 1, 1) // Point 3 (Top)
gl.TexCoord2f(1, 1)
gl.Vertex3f(1, 1, -1) // Point 4 (Top)
// Bottom Face 底面
gl.Normal3f(0, -1, 0) // Normal Pointing Down 法线朝下
gl.TexCoord2f(1, 1)
gl.Vertex3f(-1, -1, -1) // Point 1 (Bottom)
gl.TexCoord2f(0, 1)
gl.Vertex3f(1, -1, -1) // Point 2 (Bottom)
gl.TexCoord2f(0, 0)
gl.Vertex3f(1, -1, 1) // Point 3 (Bottom)
gl.TexCoord2f(1, 0)
gl.Vertex3f(-1, -1, 1) // Point 4 (Bottom)
// Right face 右面
gl.Normal3f(1, 0, 0) // Normal Pointing Right 法线朝右
gl.TexCoord2f(1, 0)
gl.Vertex3f(1, -1, -1) // Point 1 (Right)
gl.TexCoord2f(1, 1)
gl.Vertex3f(1, 1, -1) // Point 2 (Right)
gl.TexCoord2f(0, 1)
gl.Vertex3f(1, 1, 1) // Point 3 (Right)
gl.TexCoord2f(0, 0)
gl.Vertex3f(1, -1, 1) // Point 4 (Right)
// Left Face 左面
gl.Normal3f(-1, 0, 0) // Normal Pointing Left 法线朝左
gl.TexCoord2f(0, 0)
gl.Vertex3f(-1, -1, -1) // Point 1 (Left)
gl.TexCoord2f(1, 0)
gl.Vertex3f(-1, -1, 1) // Point 2 (Left)
gl.TexCoord2f(1, 1)
gl.Vertex3f(-1, 1, 1) // Point 3 (Left)
gl.TexCoord2f(0, 1)
gl.Vertex3f(-1, 1, -1)
gl.End()
glfw.SwapBuffers()
}
func drawScene() {
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
gl.LoadIdentity()
gl.Translatef(0, 0, z)
gl.Rotatef(rotation[0], 1, 0, 0)
gl.Rotatef(rotation[1], 0, 1, 0)
rotation[0] += speed[0]
rotation[1] += speed[1]
textures[filter].Bind(gl.TEXTURE_2D)
gl.Begin(gl.QUADS)
// Front Face
gl.Normal3f(0, 0, 1) // Normal Pointing Towards Viewer
gl.TexCoord2f(0, 0)
gl.Vertex3f(-1, -1, 1) // Point 1 (Front)
gl.TexCoord2f(1, 0)
gl.Vertex3f(1, -1, 1) // Point 2 (Front)
gl.TexCoord2f(1, 1)
gl.Vertex3f(1, 1, 1) // Point 3 (Front)
gl.TexCoord2f(0, 1)
gl.Vertex3f(-1, 1, 1) // Point 4 (Front)
// Back Face
gl.Normal3f(0, 0, -1) // Normal Pointing Away From Viewer
gl.TexCoord2f(1, 0)
gl.Vertex3f(-1, -1, -1) // Point 1 (Back)
gl.TexCoord2f(1, 1)
gl.Vertex3f(-1, 1, -1) // Point 2 (Back)
gl.TexCoord2f(0, 1)
gl.Vertex3f(1, 1, -1) // Point 3 (Back)
gl.TexCoord2f(0, 0)
gl.Vertex3f(1, -1, -1) // Point 4 (Back)
// Top Face
gl.Normal3f(0, 1, 0) // Normal Pointing Up
gl.TexCoord2f(0, 1)
gl.Vertex3f(-1, 1, -1) // Point 1 (Top)
gl.TexCoord2f(0, 0)
gl.Vertex3f(-1, 1, 1) // Point 2 (Top)
gl.TexCoord2f(1, 0)
gl.Vertex3f(1, 1, 1) // Point 3 (Top)
gl.TexCoord2f(1, 1)
gl.Vertex3f(1, 1, -1) // Point 4 (Top)
// Bottom Face
gl.Normal3f(0, -1, 0) // Normal Pointing Down
gl.TexCoord2f(1, 1)
gl.Vertex3f(-1, -1, -1) // Point 1 (Bottom)
gl.TexCoord2f(0, 1)
gl.Vertex3f(1, -1, -1) // Point 2 (Bottom)
gl.TexCoord2f(0, 0)
gl.Vertex3f(1, -1, 1) // Point 3 (Bottom)
gl.TexCoord2f(1, 0)
gl.Vertex3f(-1, -1, 1) // Point 4 (Bottom)
// Right face
gl.Normal3f(1, 0, 0) // Normal Pointing Right
gl.TexCoord2f(1, 0)
gl.Vertex3f(1, -1, -1) // Point 1 (Right)
gl.TexCoord2f(1, 1)
gl.Vertex3f(1, 1, -1) // Point 2 (Right)
gl.TexCoord2f(0, 1)
gl.Vertex3f(1, 1, 1) // Point 3 (Right)
gl.TexCoord2f(0, 0)
gl.Vertex3f(1, -1, 1) // Point 4 (Right)
// Left Face
gl.Normal3f(-1, 0, 0) // Normal Pointing Left
gl.TexCoord2f(0, 0)
gl.Vertex3f(-1, -1, -1) // Point 1 (Left)
gl.TexCoord2f(1, 0)
gl.Vertex3f(-1, -1, 1) // Point 2 (Left)
gl.TexCoord2f(1, 1)
gl.Vertex3f(-1, 1, 1) // Point 3 (Left)
gl.TexCoord2f(0, 1)
gl.Vertex3f(-1, 1, -1)
gl.End()
glfw.SwapBuffers()
}
func drawScene() {
gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
gl.MatrixMode(gl.MODELVIEW)
gl.LoadIdentity()
gl.Translatef(0, 0, -3.0)
gl.Rotatef(rotx, 1, 0, 0)
gl.Rotatef(roty, 0, 1, 0)
rotx += 0.5
roty += 0.5
texture.Bind(gl.TEXTURE_2D)
gl.Color4f(1, 1, 1, 1)
gl.Begin(gl.QUADS)
gl.Normal3f(0, 0, 1)
gl.TexCoord2f(0, 0)
gl.Vertex3f(-1, -1, 1)
gl.TexCoord2f(1, 0)
gl.Vertex3f(1, -1, 1)
gl.TexCoord2f(1, 1)
gl.Vertex3f(1, 1, 1)
gl.TexCoord2f(0, 1)
gl.Vertex3f(-1, 1, 1)
gl.Normal3f(0, 0, -1)
gl.TexCoord2f(1, 0)
gl.Vertex3f(-1, -1, -1)
gl.TexCoord2f(1, 1)
gl.Vertex3f(-1, 1, -1)
gl.TexCoord2f(0, 1)
gl.Vertex3f(1, 1, -1)
gl.TexCoord2f(0, 0)
gl.Vertex3f(1, -1, -1)
gl.Normal3f(0, 1, 0)
gl.TexCoord2f(0, 1)
gl.Vertex3f(-1, 1, -1)
gl.TexCoord2f(0, 0)
gl.Vertex3f(-1, 1, 1)
gl.TexCoord2f(1, 0)
gl.Vertex3f(1, 1, 1)
gl.TexCoord2f(1, 1)
gl.Vertex3f(1, 1, -1)
gl.Normal3f(0, -1, 0)
gl.TexCoord2f(1, 1)
gl.Vertex3f(-1, -1, -1)
gl.TexCoord2f(0, 1)
gl.Vertex3f(1, -1, -1)
gl.TexCoord2f(0, 0)
gl.Vertex3f(1, -1, 1)
gl.TexCoord2f(1, 0)
gl.Vertex3f(-1, -1, 1)
gl.Normal3f(1, 0, 0)
gl.TexCoord2f(1, 0)
gl.Vertex3f(1, -1, -1)
gl.TexCoord2f(1, 1)
gl.Vertex3f(1, 1, -1)
gl.TexCoord2f(0, 1)
gl.Vertex3f(1, 1, 1)
gl.TexCoord2f(0, 0)
gl.Vertex3f(1, -1, 1)
gl.Normal3f(-1, 0, 0)
gl.TexCoord2f(0, 0)
gl.Vertex3f(-1, -1, -1)
gl.TexCoord2f(1, 0)
gl.Vertex3f(-1, -1, 1)
gl.TexCoord2f(1, 1)
gl.Vertex3f(-1, 1, 1)
gl.TexCoord2f(0, 1)
gl.Vertex3f(-1, 1, -1)
gl.End()
}