cocos2dx spine之二 ：spine变色

cocos2dx版本为3.10

1.具体原理和代码可以参考博文《利用shader改变图片色相Hue》，下面的代码根据该博文进行整理优化。

基本原理就是将RGB值转换为HSL值后加上输入的HSL值，再转换为RGB值。

2.spine变色的思路有三种：

①spine::SkeletonAnimation调用shader

②读取spine对应的atlas文件，分析该文件得到所需的png图片，将该图片读入内存，修改内存中像素颜色，然后生成texture赋值给spine中的spAtlas->pages->rendererObject

③读取spine对应的atlas文件，分析该文件得到所需的png图片，将该图片读入内存，修改内存中像素颜色，保存为新的png图片；读取atlas文件，修改里面png名字为新png图片名字，保存为新的atlas文件；spine创建时使用新的png图片和新的atlas文件；

以上三种方法都可行，但在实现过程中我选择使用了第③种方法；

第①种方法简单易用，但是打包到一些低端的android手机时发现掉帧很厉害，所以才会有第②和第③种方法。

第②种方法经过测试也是可行的，但是破坏了spine的正常创建流程，导致对源码的修改过于复杂容易导致各种问题。

第③种方法独立在正常创建spine流程之前，更稳当可控。

3.根据资料色相H值的范围在[0,360],饱和度S值的范围在[0,1],明度L值的范围在[0,1]；在PhotoShop中(快捷键ctrl+u)可调值范围为色相H[-180,180],饱和度A[-100,100],明度I[-100,100]；

所以在代码中,H值不进行转换，S值和L值都除以100；在实际测试过程中发现，PS调试出来的效果和程序得到的效果在S/L不为0的情况下还是有区别的，具体原因不懂，估计可能是算法不一致吧。

4.第①种方法shader

①shader代码

 #ifdef GL_ES
         precision mediump float;
 #endif
         varying vec2 v_texCoord;
         uniform float u_dH;
         uniform float u_dS;
         uniform float u_dL;
         void main() {
             vec4 texColor = texture2D(CC_Texture0, v_texCoord);
             float r = texColor.r;
             float g = texColor.g;
             float b = texColor.b;
             float a = texColor.a;
             //convert rgb to hsl
             float h;
             float s;
             float l;
             {
                 float max = max(max(r, g), b);
                 float min = min(min(r, g), b);
                 //----h
                 if (max == min){
                     h = 0.0;
                 }
                 else if (max == r&&g >= b){
                     h = 60.0*(g - b) / (max - min) + 0.0;
                 }
                 else if (max == r&&g < b){
                     h = 60.0*(g - b) / (max - min) + 360.0;
                 }
                 else if (max == g){
                     h = 60.0*(b - r) / (max - min) + 120.0;
                 }
                 else if (max == b){
                     h = 60.0*(r - g) / (max - min) + 240.0;
                 }
                 //----l
                 l = 0.5*(max + min);
                 //----s
                 if (l == 0.0 || max == min){
                     s = 0.0;
                 }
                 else if (0.0 <= l&&l <= 0.5){
                     s = (max - min) / (2.0*l);
                 }
                 else if (l > 0.5){
                     s = (max - min) / (2.0 - 2.0*l);
                 }
             }
             //(h,s,l)+(dH,dS,dL) -> (h,s,l)
             h = h + u_dH;
             s = min(1.0, max(0.0, s + u_dS));
             l = l + u_dL;
             //convert (h,s,l) to rgb and got final color
             vec4 finalColor;
             {
                 float q;
                 if (l < 0.5){
                     q = l*(1.0 + s);
                 }
                 else if (l >= 0.5){
                     q = l + s - l*s;
                 }
                 float p = 2.0*l - q;
                 float hk = h / 360.0; 

                 float t[];
                 t[] = hk + 1.0 / 3.0;
                 t[] = hk;
                 t[] = hk - 1.0 / 3.0;  

                 float c[];
                 for (int i = ; i < ; i++){
                     if (t[i] < 0.0)t[i] += 1.0;
                     if (t[i] > 1.0)t[i] -= 1.0; 

                     if (t[i] < 1.0 / 6.0){
                         c[i] = p + ((q - p)*6.0*t[i]);
                     }
                     else if (1.0 / 6.0 <= t[i] && t[i] < 0.5){
                         c[i] = q;
                     }
                     else if (0.5 <= t[i] && t[i] < 2.0 / 3.0){
                         c[i] = p + ((q - p)*6.0*(2.0 / 3.0 - t[i]));
                     }
                     else{
                         c[i] = p;
                     }
                 }
                 finalColor = vec4(c[], c[], c[], a);
             }
             finalColor += vec4(u_dL, u_dL, u_dL, 0.0);
             gl_FragColor = finalColor;
         }

②调用代码

 auto glprogram = GLProgram::createWithByteArrays(ccPositionTextureColor_vert, shader_content);//如果是Sprite使用这个Shader，则需要换为ccPositionTextureColor_noMVP_vert
 GLProgramState* glState = GLProgramState::getOrCreateWithGLProgram(glprogram);

 glState->setUniformFloat("u_dH", h);
 glState->setUniformFloat("u_dS", s / );
 glState->setUniformFloat("u_dL", l / );

 skeleton_animation->setGLProgramState(glState);

5.第③种方法创建新的png文件和atlas文件

①创建新png文件函数(这里的函数实现和参考博文《利用shader改变图片色相Hue》的实现不一样，参考博文只传了一个H值，这里是直接根据shader进行的移植修改)

 Image* create_new_image_hsl(Image* image, float u_dH, float u_dS, float u_dL){
         u_dH = u_dH;
         u_dS = u_dS / 100.0f;
         u_dL = u_dL / 100.0f;

         bool hasAlpha = image->hasAlpha();
         Texture2D::PixelFormat pixelFormat = image->getRenderFormat();
         int bit_per_pixel = image->getBitPerPixel(); //每像素多少位
         unsigned int length = image->getWidth()*image->getHeight();

         if (hasAlpha){
             //只处理了RGBA8888的格式
             if (pixelFormat == Texture2D::PixelFormat::RGBA8888){
                 unsigned int* inPixel32 = (unsigned int*)image->getData();
                 for (unsigned int i = ; i < length; ++i, ++inPixel32)
                 {
                     unsigned char cr = (*inPixel32 >> ) & 0xFF; // R
                     unsigned char cg = (*inPixel32 >> ) & 0xFF; // G
                     unsigned char cb = (*inPixel32 >> ) & 0xFF; // B
                     unsigned char ca = (*inPixel32 >> ) & 0xFF; // A
                     //透明图层不做处理
                     if (ca){
                         float r = cr*1.0f / 0xFF;
                         float g = cg*1.0f / 0xFF;
                         float b = cb*1.0f / 0xFF;

                         float h = ;
                         float s = ;
                         float l = ;
                         {
                             float max = r > g ? r : g;
                             max = max > b ? max : b;

                             float min = r < g ? r : g;
                             min = min < b ? min : b;

                             //----h
                             if (max == min){
                                 h = ;
                             }
                             else if (max == r && g >= b){
                                 h = 60.0f*(g - b) / (max - min);
                             }
                             else if (max == r && g < b){
                                 h = 60.0f*(g - b) / (max - min) + 360.0f;
                             }
                             else if (max == g){
                                 h = 60.0f*(b - r) / (max - min) + 120.0f;
                             }
                             else if (max == b){
                                 h = 60.0f*(r - g) / (max - min) + 240.0f;
                             }
                             //----l
                             l = 0.5f*(max + min);
                             //----s
                             if (l ==  || max == min){
                                 s = ;
                             }
                             else if ( <= l&&l <= 0.5f){
                                 s = (max - min) / (2.0f*l);
                             }
                             else if (l > 0.5f){
                                 s = (max - min) / (2.0f - 2.0f*l);
                             }
                         }
                         //(h,s,l)+(dH,dS,dL) -> (h,s,l)
                         h = h + u_dH;
                         s =  > s + u_dS ?  : s + u_dS;
                         s = s < 1.0f ? s : 1.0f;

                         l = l + u_dL;
                         //convert (h,s,l) to rgb and got final color

                         //vec4 finalColor;
                         {
                             float q;
                             if (l < 0.5f){
                                 q = l*(1.0f + s);
                             }
                             else if (l >= 0.5f){
                                 q = l + s - l*s;
                             }
                             float p = 2.0f*l - q;
                             float hk = h / 360.0f;

                             float t[] = {};
                             t[] = hk + 1.0f / 3.0f;
                             t[] = hk;
                             t[] = hk - 1.0f / 3.0f;

                             float c[] = {};
                             for (int i = ; i < ; i++){
                                 if (t[i] < ){
                                     t[i] += 1.0f;
                                 }
                                 if (t[i] > 1.0f){
                                     t[i] -= 1.0f;
                                 }

                                 if (t[i] < 1.0f / 6.0f){
                                     c[i] = p + ((q - p)*6.0f*t[i]);
                                 }
                                 else if (1.0f / 6.0f <= t[i] && t[i] < 0.5f){
                                     c[i] = q;
                                 }
                                 else if (0.5f <= t[i] && t[i] < 2.0f / 3.0f){
                                     c[i] = p + ((q - p)*6.0f*(2.0f / 3.0f - t[i]));
                                 }
                                 else{
                                     c[i] = p;
                                 }
                             }
                             //finalColor = vec4(c[0], c[1], c[2], a);

                             r = c[];
                             g = c[];
                             b = c[];
                         }

                         //finalColor += vec4(u_dL, u_dL, u_dL, 0.0);
                         r += u_dL;
                         g += u_dL;
                         b += u_dL;
                         //限制rgb值的有效范围
                         if (r > 1.0f) r = 1.0f;
                         if (g > 1.0f) g = 1.0f;
                         if (b > 1.0f) b = 1.0f;
                         if (r < ) r = ;
                         if (g < ) g = ;
                         if (b < ) b = ;

                         unsigned char final_r = r * 0xFF;
                         unsigned char final_g = g * 0xFF;
                         unsigned char final_b = b * 0xFF;
                         unsigned char final_a = ca;

                         unsigned int val = final_a;
                         val = val << ;
                         val |= final_b;
                         val = val << ;
                         val |= final_g;
                         val = val << ;
                         val |= final_r;

                         *inPixel32 = val;
                     }
                 }
             }
         }

         return image;
     }

②分析atlas文件，得到对应的png文件，并生成新png文件和atlas文件

 bool create_new_png_and_atlas(const char* atlas_name_no_extension, float u_dH, float u_dS, float u_dL)
     {
         bool ret = false;

         std::string atlas_name = atlas_name_no_extension;
         atlas_name += ".atlas";
         std::string atlas_file_full_name = FileUtils::getInstance()->fullPathForFilename(atlas_name);
         Data data = FileUtils::getInstance()->getDataFromFile(atlas_file_full_name);

         if (!data.isNull()){
             std::string writeable_path = FileUtils::getInstance()->getWritablePath();

             char* orginal_atlas_content = new char[data.getSize()]();
             memcpy(orginal_atlas_content, data.getBytes(), data.getSize());

             char sz_new_atlas_path[] = {};
             sprintf(sz_new_atlas_path, "%s%s_%d_%d_%d.atlas", writeable_path.c_str(), atlas_name_no_extension, (int)u_dH, (int)u_dS, (int)u_dL);

             //为了保证大小，创建一个两倍大小的内存大小(这里可以适当减少大小)
             unsigned char* new_atlas_content = new unsigned char[ * data.getSize()]();
             memset(new_atlas_content, ,  * data.getSize());

             //分析得出png文件名字，可能有分为多个png的情况
             std::vector<std::string> png_no_extension_list;
             int line_start_idx = , line_end_idx = ;
             int orginal_content_start_idx = , new_content_idx = , new_content_total_len = ;

             for (int i = ; i < data.getSize(); ++i){
                 line_end_idx = i;

                 //每一行判断是否为png
                 if (orginal_atlas_content[i] == '\n'){
                     int line_len = line_end_idx - line_start_idx;

                     //处理是图片的情况
                     if (line_len >  && orginal_atlas_content[line_end_idx - ] == '.' &&
                         (orginal_atlas_content[line_end_idx - ] == 'p' || orginal_atlas_content[line_end_idx - ] == 'P') &&
                         (orginal_atlas_content[line_end_idx - ] == 'n' || orginal_atlas_content[line_end_idx - ] == 'N') &&
                         (orginal_atlas_content[line_end_idx - ] == 'g' || orginal_atlas_content[line_end_idx - ] == 'G')){
                         //将png行前面的数据拷贝进来
                         int cpy_len = line_start_idx - orginal_content_start_idx;
                         if (cpy_len > ){
                             memcpy(new_atlas_content + new_content_idx, orginal_atlas_content + orginal_content_start_idx, cpy_len);
                             new_content_idx += cpy_len;
                             new_content_total_len += cpy_len;
                         }

                         //没有后缀的png的名字
                         char png_name_no_extension[] = {};
                         memcpy(png_name_no_extension, orginal_atlas_content + line_start_idx, line_len - );
                         png_no_extension_list.push_back(png_name_no_extension);

                         //记录列表
                         char sz_new_png_name[] = {};
                         sprintf(sz_new_png_name, "%s_%d_%d_%d.png\n", png_name_no_extension, (int)u_dH, (int)u_dS, (int)u_dL);

                         //将图片名字写入新内容
                         cpy_len = strlen(sz_new_png_name);
                         memcpy(new_atlas_content + new_content_idx, sz_new_png_name, cpy_len);
                         new_content_idx += cpy_len;
                         new_content_total_len += cpy_len;

                         orginal_content_start_idx = line_end_idx + ;
                     }

                     line_start_idx = line_end_idx + ;
                 }
             }

             //将最后一个png行到最后那部分数据也拷贝进来
             if (data.getSize() > orginal_content_start_idx){
                 int cpy_len = data.getSize() - orginal_content_start_idx;
                 memcpy(new_atlas_content + new_content_idx, orginal_atlas_content + orginal_content_start_idx, cpy_len);
                 new_content_total_len += cpy_len;
             }

             Data data;
             data.copy(new_atlas_content, new_content_total_len);

             if (!FileUtils::getInstance()->writeDataToFile(data, sz_new_atlas_path)){
                 cocos2d::log("========!!! save file %s error !!!========.", sz_new_atlas_path);
             }
             else{
                 ret = true;
             }

             data.clear();

             delete[]orginal_atlas_content;
             delete[]new_atlas_content;

             if (png_no_extension_list.size() <= ){
                 cocos2d::log("========!!! png_name_list is empty error !!!========.");
                 return false;
             }

             if (!ret){
                 return false;
             }

             //写入新图片
             for (std::vector<std::string>::iterator it = png_no_extension_list.begin(); it != png_no_extension_list.end(); ++it){
                 if (!ret){
                     break;
                 }

                 char sz_new_png_path[] = {};
                 sprintf(sz_new_png_path, "%s%s_%d_%d_%d.png", writeable_path.c_str(), it->c_str(), (int)u_dH, (int)u_dS, (int)u_dL);

                 char sz_png_name[] = {};
                 sprintf(sz_png_name, "%s.png", it->c_str());
                 std::string png_file_full_name = FileUtils::getInstance()->fullPathForFilename(sz_png_name);

                 Image* image = new Image();
                 if (image->initWithImageFile(png_file_full_name)){
                     if (Image* new_image = create_new_image_hsl(image, u_dH, u_dS, u_dL)){
                         if (!new_image->saveToFile(sz_new_png_path, false)){
                             cocos2d::log("========!!! save file %s error !!!========.", sz_new_png_path);
                             ret = false;
                         }
                     }
                     else{
                         cocos2d::log("========!!! create_new_image_hsl %s error !!!========.", sz_new_png_path);
                         ret = false;
                     }
                 }
                 else{
                     cocos2d::log("========!!! initWithImageFile %s error !!!========.", png_file_full_name.c_str());
                     ret = false;
                 }

                 delete image;
             }
         }

         return ret;
     }

6.实现效果

①原图

②PhotoShop中调到115,0,0的效果

③传入参数115,0,0后创建新Image的效果

可以看到，使用ps修改的效果和程序输出的效果基本一样。

以上，完。