该函数创建一个新表面并返回它。
首次创建表面时，它可能包含 " 噪声"，因为基本上它只是为此目的而保留的内存区域 (并且该内存可能仍然包含信息)，因此您可能需要在使用之前清除表面类似 draw_clear_alpha 的函数。
强烈建议所有表面的大小均为 2 的幂，例如大小为 16、128、512 或 1024 像素。这在某些平台 (如 Windows 和 MacOS) 上并不是完全必要的，但它肯定会提高这些目标的兼容性，而对于 HTML5 和设备来说，这是必不可少的，并且记住这一点非常重要，否则以后可能会遇到问题。
您可以选择指定将用于在内存中存储表面 数据的格式。默认格式为 surface_rgba8unorm。
创建表面 时，可以使用以下任何一种格式：
| Surface Format Constant | |
|---|---|
| 常量 | 描述 |
| surface_rgba8unorm | (Default) This format supports 4 channels (red, green, blue, alpha) with 8 bits each, meaning each channel has a 0-255 range "unorm" refers to these values being normalised into a 0-1 range when read in shaders |
| surface_r8unorm | This format supports a single channel (red) with an 8-bit value (0-255) Since it only contains one channel, it takes a quarter of the space compared to the format above (which stores RGBA) When read in a shader, all channels except red will be 0 |
| surface_rg8unorm | This is similar to the format above, however it contains two channels: red and green |
| surface_rgba4unorm | This format supports 4 channels (red, green, blue, alpha) with 4 bits each, meaning each channel has a 0-15 range |
| surface_rgba16float | This format supports 4 channels (red, green, blue, alpha) with each channel being a 16-bit float, providing a higher precision An example use case is HDR, as this format would allow you to use values past the default 0-255 colour range |
| surface_r16float | This format supports a single channel (red) with a 16-bit floating point value Since it only contains one channel, it takes a quarter of the space compared to the format above (which stores RGBA) When read in a shader, all channels except red will be 0 |
| surface_rgba32float | This format supports 4 channels (red, green, blue, alpha) with each channel being a 32-bit float, providing the highest precision, however this is slower to render to than 16-bit formats and is not as widely supported |
| surface_r32float | This format supports a single channel (red) with a 32-bit floating point value |
surface_create(w, h, [format]);
| 参数 | 类型 | 描述 |
|---|---|---|
| w | Real | 要创建的表面的宽度 |
| h | Real | 要创建的表面的高度 |
| format | Surface Format Constant | 可选 用于存储表面数据的格式，默认为 surface_rgba8unorm |
Surface (or -1 if anything went wrong)
if (!surface_exists(surf))
{
surf = surface_create(1024, 1024);
surface_set_target(surf);
draw_clear_alpha(c_black, 0);
surface_reset_target();
view_surface_id[0] = surf;
}
上面的代码检查表面是否存在，如果不存在，则会创建一个宽 1024 像素、高 1024 像素的表面，并将其分配给变量 "surf"。然后将绘图目标设置为新表面，在将绘图目标重置为显示器之前，该表面将被清除并变得透明。最后将表面分配给视图。