2014年2月25日星期二（DEMO8-2，光照图调制）

来源：互联网发布：济宁seo 编辑：程序博客网时间：2024/06/05 05:41

粗略看了下，这个DEMO加上了个光照图，

首先定义了个灯光数量，

#define NUM_LAMP 4

以及光照图数组

BITMAP_IMAGE lightmaps[NUM_LAMP];

初始化时，位置不同了

{

bitmap->Create_Bitmap( & textures[itext], ( SCREEN_WIDTH / 2) - 4 *( TEXTSIZE / 2), ( SCREEN_HEIGHT / 2 ) - 2 *( TEXTSIZE / 2), TEXTSIZE, TEXTSIZE, 16 );

bitmap->Create_Bitmap( & temp_text, ( SCREEN_WIDTH / 2) - ( TEXTSIZE / 2), ( SCREEN_HEIGHT / 2) + ( TEXTSIZE / 2), TEXTSIZE, TEXTSIZE, 16 );

光照图的初始化

bitmap->Load_Bitmap_File( & bitmap16bit, "lightmaps128_24.BMP");

for ( int itext = 0; itext < NUM_LAMP; itext++)

{

bitmap->Create_Bitmap( & lightmaps[itext], ( SCREEN_WIDTH / 2) + 2 *( TEXTSIZE / 2), ( SCREEN_HEIGHT / 2 ) - 2 *( TEXTSIZE / 2), TEXTSIZE, TEXTSIZE, 16 );

bitmap->Load_Image_Bitmap16( & lightmaps[itext],&bitmap16bit, itext % 4, itext / 4, BITMAP_EXTRACT_MODE_CELL );

}

bitmap->Unload_Bitmap_File( &bitmap16bit );

把数值改了下

int curr_texture = 7;

float scalef = 0.5;

int curr_lightmap = 1;

这个DEMO是用了下面方式调制

Pixel_dest[x,y]rgb = pixel_source[x,y]rgb * ambient +

// pixel_source[x,y]rgb * light_map[x,y]rgb

其实，知道原理了，剩下的都顺理成章了

USHORT * sbuffer = ( USHORT * )textures[curr_texture].buffer;

USHORT * lbuffer = ( USHORT * )lightmaps[curr_lightmap].buffer;

USHORT * tbuffer = ( USHORT * )temp_text.buffer;

for ( int iy = 0; iy < temp_text.height; iy ++)

{

for ( int ix = 0; ix < temp_text.width; ix ++)

{

int rs, gs, bs;

int rl, gl, bl;

int rf, gf, bf;

USHORT spixel = sbuffer[iy * temp_text.width + ix];

_RGB565FROM16BIT( spixel, &rs, &gs, &bs );

USHORT lpixel = lbuffer[iy * temp_text.width + ix];

_RGB565FROM16BIT( lpixel, &rs, &gs, &bs );

rf = ( scalef * (float) rs ) + ( (float) rs * (float )rl/(float)64 );

gf = ( scalef * (float) gs ) + ( (float) gs * (float )rl/(float)64 );

bf = ( scalef * (float) bs ) + ( (float) bs * (float )rl/(float)64 );

if ( rf > 255 )

{

rf = 255;

}

if ( gf > 255 )

{

gf = 255;

}

if ( bf > 255 )

{

bf = 255;

}

tbuffer[iy * temp_text.width + ix] = _RGB16BIT565( rf, gf, bf );

}

bitmap->Draw_Bitmap16( &temp_text, ddraw->getbackbuffer(), ddraw->getbacklpitch(), 0);

bitmap->Draw_Bitmap16( &textures[curr_texture], ddraw->getbackbuffer(), ddraw->getbacklpitch(), 0);

bitmap->Draw_Bitmap16( &lightmaps[curr_lightmap], ddraw->getbackbuffer(), ddraw->getbacklpitch(), 0);

结果如下图

0 0