Question

我有一个负责任的功能，用于在屏幕上绘制一个矩形，它在我的程序的主循环内，它执行此操作：

DrawRetangle (SDL_Renderer * Renderer, SDL_Rect MyRect) {

    // Clean the renderer
    SDL_RenderClear (Renderer);

   // Position x, y, width and height of the rectangle.
    MyRect = {x, y, width, height};

    // Rectangle border color
    SDL_SetRenderDrawColor (Renderer, 0, 0, 0, 255);

    // Draw the edges of the rectangle
    SDL_RenderDrawRect (Renderer, & MyRect);

    // Color from within the rectangle
    SDL_SetRenderDrawColor (Renderer, 255, 255, 255, 255);

    // Fill in the rectangle
    SDL_RenderFillRect (Renderer, & MyRect);

    // Show in window
    SDL_RenderPresent (Renderer);

}

请注意，我正在尝试绘制一个带有黑色边框并填充白色的矩形，但它全部变黑，我知道我可以解决这个问题，清洁，绘制边框，显示，清洁，绘制内部和显示，但是，如果我对多个矩形进行分层，这将是不好的，有更好的方法吗？

Up 1：

功能是否就是这样，如下所示？

DrawRetangle (SDL_Renderer * Renderer, SDL_Rect MyRect) {

    // Clean the renderer 1
    SDL_RenderClear (Renderer);

   // Position x, y, width and height of the rectangle.
    MyRect = {x, y, width, height};

    // Rectangle border color
    SDL_SetRenderDrawColor (Renderer, 0, 0, 0, 255);

    // Draw the edges of the rectangle
    SDL_RenderDrawRect (Renderer, & MyRect);

    // Show in window 1
    SDL_RenderPresent (Renderer);

    // Clean the renderer 2
    SDL_RenderClear (Renderer);

    // Color from within the rectangle
    SDL_SetRenderDrawColor (Renderer, 255, 255, 255, 255);

    // Fill in the rectangle
    SDL_RenderFillRect (Renderer, & MyRect);

    // Show in window 2
    SDL_RenderPresent (Renderer);

}

Up 2：

我找到的另一个解决方案是将下面的函数调用两次，在另一个上面创建一个矩形，一个稍小的内部，看起来像边框。但我仍然认为这不应该是最好的方法。

DrawRetangle (SDL_Renderer * Renderer, SDL_Rect MyRect, int x, int, y, int width, int height, int r, int g, int b, int a) {

       // Position x, y, width and height of the rectangle.
        MyRect = {x, y, width, height};


        // Color from within the rectangle
        SDL_SetRenderDrawColor (Renderer, r, g, b, a);

           // Clean the renderer
        SDL_RenderClear (Renderer);

        // Fill in the rectangle
        SDL_RenderFillRect (Renderer, & MyRect);

        // Show in window
        SDL_RenderPresent (Renderer);

    }

Answer 1

在绘制填充矩形之前

更改矩形的大小和位置。然后试试。

Myrect->x+=borderSize; //whatever size you want
Myrect->y+=borderSize;
Myrect->h-=(borderSize*2);
Myrect->w-=(borderSize*2);
    // Color from within the rectangle
SDL_SetRenderDrawColor (Renderer, 255, 255, 255, 255);

// Fill in the rectangle
SDL_RenderFillRect (Renderer, & MyRect);

如何为边框和不同颜色的矩形着色？ SDL

1 个答案: