Luna/libui/src/Canvas.cpp

/**
 * @file Canvas.cpp
 * @author apio (cloudapio.eu)
 * @brief Drawable surfaces.
 *
 * @copyright Copyright (c) 2023, the Luna authors.
 *
 */

#include <ui/Canvas.h>

namespace ui
{
    Canvas Canvas::create(u8* ptr, int width, int height)
    {
        return Canvas { .width = width, .height = height, .stride = width, .ptr = ptr };
    }

    Canvas Canvas::subcanvas(Rect rect)
    {
        if (rect.pos.x < 0) rect.pos.x = 0;
        if (rect.pos.y < 0) rect.pos.y = 0;
        if (rect.pos.x + rect.width > width) rect.width = width - rect.pos.x;
        if (rect.pos.y + rect.height > height) rect.height = height - rect.pos.y;

        u8* p = ptr + rect.pos.x * sizeof(Color) + (rect.pos.y * sizeof(Color) * stride);

        return Canvas { .width = rect.width, .height = rect.height, .stride = stride, .ptr = p };
    }

    void Canvas::fill(Color color)
    {
        u8* p = ptr;
        for (int i = 0; i < height; i++)
        {
            u32* colorp = (u32*)p;
            for (int j = 0; j < width; j++)
            {
                *colorp = color.raw;
                colorp++;
            }
            p += stride * sizeof(Color);
        }
    }

    void Canvas::fill(u32* pixels, int _stride)
    {
        u8* p = ptr;
        for (int i = 0; i < height; i++)
        {
            u32* colorp = (u32*)p;
            for (int j = 0; j < width; j++)
            {
                u32 pix = pixels[j];
                if (Color::from_u32(pix).alpha() == 0xff) *colorp = pix;
                colorp++;
            }
            pixels += _stride;
            p += stride * sizeof(Color);
        }
    }
}