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The float4 structure encapsulates 4 float values and can be used to represent a 4-element vector or a row of a 4-column matrix:
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | struct float4 { float4() {}; float4( float s) : x(s), y(s), z(s), w(s) {} float4( float x, float y, float z, float w) : x(x), y(y), z(z), w(w) {} float x, y, z, w; inline float4 operator*( float s) const { return float4(x*s, y*s, z*s, w*s); } inline float4 operator+( const float4& a) const { return float4(x+a.x, y+a.y, z+a.z, w+a.w); } }; // dot product of two float4 vectors inline float dot( const float4& a, const float4& b) { return a.x * b.x + a.y * b.y + a.z * b.z + a.w * b.w; } |
Similar to the float4 datatype, we define another common type: float3. It can be used, for example, for representing 3D vectors.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | struct float3 { float3() {}; float3( float s) : x(s), y(s), z(s) {} float3( float x, float y, float z) : x(x), y(y), z(z) {} float x, y, z; inline float3 operator*( float s) const { return float3(x*s, y*s, z*s); } inline float3 operator+( const float3& a) const { return float3(x+a.x, y+a.y, z+a.z); } }; // dot product of two float3 vectors inline float dot( const float3& a, const float3& b) { return a.x * b.x + a.y * b.y + a.z * b.z; } |
The float2 datatype contains 2 float elements:
| 1 2 3 4 5 6 7 | struct float3 { float2() {}; float2( float s) : x(s), y(s) {} float2( float x, float y) : x(x), y(y) {} float x, y; }; |
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