/**
* 将色彩类型为RGBA的前景图像，合成至目标背景图像中
* param back
* 背景图像
* param des_rect
* 背景图像中的写入区域
* param fore
* 前景图像
* param src_pos
* 前景图像中的读取区域的坐标
* warning
* 此函数不会对传入的参数进行有效性判断，因为此函数主要被Graph_Mix函
* 数调用，Graph_Mix函数会预先进行参数有效性判断
*/
static void Graph_RGBAMix( LCUI_Graph *des,
LCUI_Rect des_rect,
LCUI_Graph *src,
LCUI_Pos src_pos )
{
int x, y;
int src_n, des_n;
int des_row_start, src_row_start;
/* 计算并保存第一行的首个像素的位置 */
src_row_start = src_pos.y * src->w + src_pos.x;
des_row_start = des_rect.y * des->w + des_rect.x;
for(y=0; y<des_rect.height; ++y) {
des_n = des_row_start;
src_n = src_row_start;
for(x=0; x<des_rect.width; ++x) {
/* 将R、G、B三个色彩值进行alpha混合 */
ALPHA_BLEND( src->rgba[0][src_n], des->rgba[0][des_n], src->rgba[3][src_n] );
ALPHA_BLEND( src->rgba[1][src_n], des->rgba[1][des_n], src->rgba[3][src_n] );
ALPHA_BLEND( src->rgba[2][src_n], des->rgba[2][des_n], src->rgba[3][src_n] );
/* 切换到下个像素的数据 */
++src_n;
++des_n;
}
/* 切换到下一行像素 */
des_row_start += des->w;
src_row_start += src->w;
}
}
/**
* 将色彩类型为RGB的前景图像，合成至目标背景图像中
* 在进行alpha混合时，会将源图像的全局透明度计算在内进行混合
* param back
* 背景图像
* param des_rect
* 背景图像中的写入区域
* param fore
* 前景图像
* param src_pos
* 前景图像中的读取区域的坐标
* warning
* 此函数不会对传入的参数进行有效性判断，因为此函数主要被Graph_Mix函
* 数调用，Graph_Mix函数会预先进行参数有效性判断
*/
static void Graph_RGBMixWithGlobalAlpha( LCUI_Graph *des,
LCUI_Rect des_rect,
LCUI_Graph *src,
LCUI_Pos src_pos )
{
int x, y;
int src_n, des_n;
int des_row_start, src_row_start;
src_row_start = src_pos.y * src->w + src_pos.x;
des_row_start = des_rect.y * src->w + des_rect.x;
for(y=0; y<des_rect.height; ++y) {
des_n = des_row_start;
src_n = src_row_start;
for(x=0; x<des_rect.width; ++x) {
ALPHA_BLEND( src->rgba[0][src_n],
des->rgba[0][des_n],
src->alpha );
ALPHA_BLEND( src->rgba[1][src_n],
des->rgba[1][des_n],
src->alpha );
ALPHA_BLEND( src->rgba[2][src_n],
des->rgba[2][des_n],
src->alpha );
++des_n;
++src_n;
}
}
}
extern inline void
mix_pixel( uchar_t **buff, int pos, LCUI_RGB color, uchar_t alpha )
{
ALPHA_BLEND( color.red, buff[0][pos], alpha );
ALPHA_BLEND( color.blue, buff[1][pos], alpha );
ALPHA_BLEND( color.green, buff[2][pos], alpha );
}
static void Graph_ARGBMixARGB( LCUI_Graph *des, LCUI_Rect des_rect,
const LCUI_Graph *src, LCUI_Pos src_pos )
{
int x, y, val;
uchar_t alpha;
LCUI_ARGB *px_src, *px_des;
LCUI_ARGB *px_row_src, *px_row_des;
/* 计算并保存第一行的首个像素的位置 */
px_row_src = src->argb + src_pos.y*src->w + src_pos.x;
px_row_des = des->argb + des_rect.y*des->w + des_rect.x;
if( src->opacity < 1.0 ) {
for( y=0; y<des_rect.h; ++y ) {
px_src = px_row_src;
px_des = px_row_des;
for( x=0; x<des_rect.w; ++x ) {
alpha = px_src->a * src->opacity;
/* 将R、G、B三个色彩值进行alpha混合 */
ALPHA_BLEND( px_des->r, px_src->r, alpha );
ALPHA_BLEND( px_des->g, px_src->g, alpha );
ALPHA_BLEND( px_des->b, px_src->b, alpha );
if( px_des->alpha == 255 || px_src->alpha == 255 ) {
px_des->alpha = 255;
} else {
/* alpha = 1.0 - (1.0 - a1)*(1.0 - a2) */
val = (255 - px_src->alpha)*(255 - px_des->alpha);
px_des->alpha = (uchar_t)(255 - val / 65025);
}
/* 切换到下个像素的数据 */
++px_src;
++px_des;
}
/* 切换到下一行像素 */
px_row_des += des->w;
px_row_src += src->w;
}
return;
}
for( y=0; y<des_rect.h; ++y ) {
px_src = px_row_src;
px_des = px_row_des;
for( x=0; x<des_rect.w; ++x ) {
ALPHA_BLEND( px_des->r, px_src->r, px_src->a );
ALPHA_BLEND( px_des->g, px_src->g, px_src->a );
ALPHA_BLEND( px_des->b, px_src->b, px_src->a );
if( px_des->alpha == 255 || px_src->alpha == 255 ) {
px_des->alpha = 255;
} else {
val = (255 - px_src->alpha)*(255 - px_des->alpha);
px_des->alpha = (uchar_t)(255 - val / 65025);
}
++px_src;
++px_des;
}
px_row_des += des->w;
px_row_src += src->w;
}
}
/**
* 将色彩类型为RGBA的前景图像，合成至目标背景图像中
* 在进行alpha混合时，会将源图像的全局透明度计算在内进行混合
* param back
* 背景图像
* param des_rect
* 背景图像中的写入区域
* param fore
* 前景图像
* param src_pos
* 前景图像中的读取区域的坐标
* warning
* 此函数不会对传入的参数进行有效性判断，因为此函数主要被Graph_Mix函
* 数调用，Graph_Mix函数会预先进行参数有效性判断
*/
static void Graph_RGBAMixWithGlobalAlpha( LCUI_Graph *des,
LCUI_Rect des_rect,
LCUI_Graph *src,
LCUI_Pos src_pos )
{
double k;
int x, y;
uchar_t alpha;
int src_n, des_n;
int des_row_start, src_row_start;
src_row_start = src_pos.y * src->w + src_pos.x;
des_row_start = des_rect.y * des->w + des_rect.x;
/* 先得出透明度比例，避免在循环中进行除法运算 */
k = src->alpha / 255.0;
for (y=0; y < des_rect.height; ++y) {
des_n = des_row_start;
src_n = src_row_start;
for(x=0; x<des_rect.width; ++x) {
alpha = src->rgba[3][src_n] * k;
ALPHA_BLEND( src->rgba[0][src_n],
des->rgba[0][des_n],
alpha );
ALPHA_BLEND( src->rgba[1][src_n],
des->rgba[1][des_n],
alpha );
ALPHA_BLEND( src->rgba[2][src_n],
des->rgba[2][des_n],
alpha );
++des_n;
++src_n;
}
src_row_start += src->w;
des_row_start += des->w;
}
}
static void Blit1toNAlphaKey(SDL_BlitInfo *info)
{
int width = info->d_width;
int height = info->d_height;
int srcskip = info->s_skip;
int dstskip = info->d_skip;
SDL_PixelFormat *srcfmt = info->src;
SDL_PixelFormat *dstfmt = info->dst;
const SDL_Color *srcpal = info->src->palette->colors;
uint32_t ckey = srcfmt->colorkey;
const int A = srcfmt->alpha;
int dstbpp = dstfmt->BytesPerPixel;
uint8_t *src = info->s_pixels;
uint8_t *dst = info->d_pixels;
while ( height-- )
{
int dR, dG, dB;
int n;
for (n = width; n > 0; --n)
{
if ( *src != ckey )
{
uint32_t pixel;
int sR = srcpal[*src].r;
int sG = srcpal[*src].g;
int sB = srcpal[*src].b;
DISEMBLE_RGB(dst, dstbpp, dstfmt,
&pixel, &dR, &dG, &dB);
ALPHA_BLEND(sR, sG, sB, A, &dR, &dG, &dB);
ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB);
}
src++;
dst += dstbpp;
}
src += srcskip;
dst += dstskip;
}
}
/** 将字体位图绘制到目标图像上 */
int FontBMP_Mix( LCUI_Graph *graph, LCUI_Pos pos,
LCUI_FontBMP *bmp, LCUI_Color color )
{
int val, x, y;
LCUI_Graph *des;
LCUI_Rect des_rect, cut;
LCUI_ARGB *px_des, *px_row_des;
uchar_t *bmp_src, *bmp_row_src, *byte_row_des, *byte_des;
/* 数据有效性检测 */
if( !FontBMP_IsValid( bmp ) || !Graph_IsValid( graph ) ) {
return -1;
}
/* 获取背景图形的有效区域 */
Graph_GetValidRect( graph, &des_rect );
/* 获取背景图引用的源图形 */
des = Graph_GetQuote( graph );
/* 起点位置的有效性检测 */
if(pos.x > des->w || pos.y > des->h) {
return -2;
}
/* 获取需要裁剪的区域 */
LCUIRect_GetCutArea( Size( des_rect.width, des_rect.height ),
Rect( pos.x, pos.y, bmp->width, bmp->rows ), &cut );
pos.x += cut.x;
pos.y += cut.y;
if( graph->color_type == COLOR_TYPE_ARGB ) {
bmp_row_src = bmp->buffer + cut.y*bmp->width + cut.x;
px_row_des = des->argb + (pos.y + des_rect.y) * des->w;
px_row_des += pos.x + des_rect.x;
for( y=0; y<cut.h; ++y ) {
bmp_src = bmp_row_src;
px_des = px_row_des;
for( x=0; x<cut.w; ++x ) {
ALPHA_BLEND( px_des->r, color.r, *bmp_src );
ALPHA_BLEND( px_des->g, color.g, *bmp_src );
ALPHA_BLEND( px_des->b, color.b, *bmp_src );
if( px_des->alpha == 255 || *bmp_src == 255 ) {
px_des->alpha = 255;
} else {
val = (255 - *bmp_src)*(255 - px_des->alpha);
px_des->alpha = (uchar_t)(255 - val / 65025);
}
++bmp_src;
++px_des;
}
px_row_des += des->w;
bmp_row_src += bmp->width;
}
return 0;
}
bmp_row_src = bmp->buffer + cut.y*bmp->width + cut.x;
byte_row_des = des->bytes + (pos.y + des_rect.y) * des->bytes_per_row;
byte_row_des += (pos.x + des_rect.x)*des->bytes_per_pixel;
for( y=0; y<cut.h; ++y ) {
bmp_src = bmp_row_src;
byte_des = byte_row_des;
for( x=0; x<cut.w; ++x ) {
ALPHA_BLEND( *byte_des, color.b, *bmp_src );
byte_des++;
ALPHA_BLEND( *byte_des, color.g, *bmp_src );
byte_des++;
ALPHA_BLEND( *byte_des, color.r, *bmp_src );
byte_des++;
++bmp_src;
}
byte_row_des += des->w*3;
bmp_row_src += bmp->width;
}
return 0;
}