我想围绕轴旋转我的屏幕上的立方体。
我在javascript中找到了这个使用3D旋转矩阵的例子。我尝试在我的应用程序中制作类似的东西但是立方体不想旋转,我不知道问题出在哪里。
立方体在不同的位置移动(例如从完美的角度观看),但直到该视图才显示运动。从顶部,底部,正面和侧面看都是如此。
这是我的代码:
dimension: Integer = 1;
a: Integer = 0;
b: Integer = 0;
ite: Integer = 27;
ite1: Integer;
ite2: Integer;
ite3: Integer;
x: Integer;
y: Integer;
z: Integer;
u: Integer = 0;
v: Integer = 0;
w: Integer = 0;
u2: Integer = 0;
v2: Integer = 0;
w2: Integer = 0;
c: Integer = 0;
pts: TpointArray;
ite := 0;
a := round(Mouse.CursorPos.X/99);
b := round(Mouse.CursorPos.Y/99);
for x := -dimension to dimension do
begin
for y := -dimension to dimension do
begin
for z := -dimension to dimension do
begin
u := x;
v := y;
w := z;
u2 := round(u*cos(a)-v*sin(a));
v2 := round(u*sin(a)+v*cos(a));
w2 := w;
u := u2; v := v2; w := w2;
u2 := u;
v2 := round(v*cos(b)-w*sin(b));
w2 := round(v*sin(b)+w*cos(b));
u := u2; v := v2; w := w2;
pts[ite].X := 200+u*(w+2)*30;
pts[ite].Y := 200+v*(w+2)*30;
Ellipse(pts[ite].X,pts[ite].Y,pts[ite].X+10,pts[ite].Y+10);
ite := ite + 1;
end;
end;
end;
for ite1 := 0 to 25 do
begin
for ite2 := 1 to 26 do
begin
MoveTo(pts[ite1].X,pts[ite1].Y);
LineTo(pts[ite2].X,pts[ite2].Y);
end;
end;
问题出在哪里?
答案 0 :(得分:7)
您使用整数表示角度。 cos和sin函数使用浮点数(弧度)。所以在你的情况下,旋转角度会变化〜57度离散。
答案 1 :(得分:2)
解决方案如下所示:
a: Double = 0;
b: Double = 0;
ite: Integer = 27;
ite1: Integer;
ite2: Integer;
ite3: Integer;
x: Integer;
y: Integer;
z: Integer;
u: Double = 0;
v: Double = 0;
w: Double = 0;
u2: Double = 0;
v2: Double = 0;
w2: Double = 0;
c: Integer = 0;
pts: TpointArray;
ite := 0;
a := Mouse.CursorPos.X/99;
b := Mouse.CursorPos.Y/99;
for x := -dimension to dimension do
begin
for y := -dimension to dimension do
begin
for z := -dimension to dimension do
begin
u := x;
v := y;
w := z;
u2 := u*cos(a)-v*sin(a);
v2 := u*sin(a)+v*cos(a);
w2 := w;
u := u2; v := v2; w := w2;
u2 := u;
v2 := v*cos(b)-w*sin(b);
w2 := v*sin(b)+w*cos(b);
u := u2; v := v2; w := w2;
pts[ite].X := round(200+u*(w+5)*30);
pts[ite].Y := round(200+v*(w+5)*30);
Ellipse(pts[ite].X,pts[ite].Y,pts[ite].X+10,pts[ite].Y+10);
ite := ite + 1;
end;
end;
end;
for ite1 := 0 to 25 do
begin
for ite2 := 1 to 26 do
begin
MoveTo(pts[ite1].X,pts[ite1].Y);
LineTo(pts[ite2].X,pts[ite2].Y);
end;
end;