Direct3D 9学习笔记(5)颜色

一.三个宏

// D3DCOLOR is equivalent to D3DFMT_A8R8G8B8
#ifndef D3DCOLOR_DEFINED
typedef DWORD D3DCOLOR;
#define D3DCOLOR_DEFINED
#endif

// maps unsigned 8 bits/channel to D3DCOLOR
#define D3DCOLOR_ARGB(a,r,g,b) \
    ((D3DCOLOR)((((a)&0xff)<<24)|(((r)&0xff)<<16)|(((g)&0xff)<<8)|((b)&0xff)))
#define D3DCOLOR_RGBA(r,g,b,a) D3DCOLOR_ARGB(a,r,g,b)
#define D3DCOLOR_XRGB(r,g,b)   D3DCOLOR_ARGB(0xff,r,g,b)

返回的是一个DWORD

二.D3DXCOLOR,D3DCOLORVALUE

一个更精确的存储颜色的数据结构

typedef struct _D3DCOLORVALUE {
    float r;
    float g;
    float b;
    float a;
} D3DCOLORVALUE;

typedef struct D3DXCOLOR
{
#ifdef __cplusplus
public:
    D3DXCOLOR() {};
    D3DXCOLOR( UINT  argb );
    D3DXCOLOR( CONST FLOAT * );
    D3DXCOLOR( CONST D3DXFLOAT16 * );
    D3DXCOLOR( FLOAT r, FLOAT g, FLOAT b, FLOAT a );

    // casting
    operator UINT  () const;

    operator FLOAT* ();
    operator CONST FLOAT* () const;

    // assignment operators
    D3DXCOLOR& operator += ( CONST D3DXCOLOR& );
    D3DXCOLOR& operator -= ( CONST D3DXCOLOR& );
    D3DXCOLOR& operator *= ( FLOAT );
    D3DXCOLOR& operator /= ( FLOAT );

    // unary operators
    D3DXCOLOR operator + () const;
    D3DXCOLOR operator - () const;

    // binary operators
    D3DXCOLOR operator + ( CONST D3DXCOLOR& ) const;
    D3DXCOLOR operator - ( CONST D3DXCOLOR& ) const;
    D3DXCOLOR operator * ( FLOAT ) const;
    D3DXCOLOR operator / ( FLOAT ) const;

    friend D3DXCOLOR operator * ( FLOAT, CONST D3DXCOLOR& );

    BOOL operator == ( CONST D3DXCOLOR& ) const;
    BOOL operator != ( CONST D3DXCOLOR& ) const;

#endif //__cplusplus
    FLOAT r, g, b, a;
} D3DXCOLOR, *LPD3DXCOLOR;

三.顶点着色

如下顶点颜色填充效果

设置方法

有颜色的顶点坐标

// Initialize three Vertices for rendering a triangle
CUSTOMVERTEX Vertices[] =
{
    { 150.0f,  50.0f, 0.5f, 1.0f, 0xffff0000, }, // x, y, z, rhw, color
    { 250.0f, 250.0f, 0.5f, 1.0f, 0xff00ff00, },
    {  50.0f, 250.0f, 0.5f, 1.0f, 0xff00ffff, },
};