> On May 1, 2018, at 3:17 PM, Michael Van Canneyt <mich...@freepascal.org>
> wrote:
>
>> So constants must be part of the class? In the example below
>> gl.COLOR_BUFFER_BIT is scoped to WebGLRenderingContext so I guess that’s the
>> reason.
>
> Yes.
>
> Constants without expression can only exist in an external class.
Just curious but why can’t you declare a const anywhere for any reasons?
>
>>
>> Also I mistyped, GLfloat is a type so how do this map to JS, or do I even
>> need to since the names are the same?
>
> You need to define types.
>
> type
> GLfloat = double;
Why do we need to redefine the type if it’s already defined in the JS library?
GLfloat isn’t a double also but see my other reply.
From the link you posted there are these types. Is that even JavaScript? I
don’t remember there being typedefs in it or void functions.
typedef unsigned long GLenum;
typedef boolean GLboolean;
typedef unsigned long GLbitfield;
typedef byte GLbyte; /* 'byte' should be a signed 8 bit type.
*/
typedef short GLshort;
typedef long GLint;
typedef long GLsizei;
typedef long long GLintptr;
typedef long long GLsizeiptr;
// Ideally the typedef below would use 'unsigned byte', but that doesn't
currently exist in Web IDL.
typedef octet GLubyte; /* 'octet' should be an unsigned 8 bit
type. */
typedef unsigned short GLushort;
typedef unsigned long GLuint;
typedef unrestricted float GLfloat;
typedef unrestricted float GLclampf;
There’s other types also like dictionaries and interface. How do those work? I
don’t remember those being in JS either….
dictionary WebGLContextAttributes
{
GLboolean alpha = true;
GLboolean depth = true;
GLboolean stencil = false;
GLboolean antialias = true;
GLboolean premultipliedAlpha = true;
GLboolean preserveDrawingBuffer = false;
WebGLPowerPreference powerPreference = "default";
GLboolean failIfMajorPerformanceCaveat = false;
};
interface WebGLActiveInfo
{
readonly attribute GLint size;
readonly attribute GLenum type;
readonly attribute DOMString name;
};
>
>>
>> How does this JS translate to Pascal then? drawingBufferWidth are read only
>> properties but no type is specified so how does Pascal handle all the
>> untyped variables we see in JS?
>
> This is pascal. You need a type.
>
> https://www.khronos.org/registry/webgl/specs/latest/1.0/
>
> shows that drawingBufferWidth has type GLsizei, which is a long.
>
> If you don't know the type, use JSValue. It's the 'unknown type'. It has
> limited possibilities, in essence you'll need to typecast a JSValue before
> using it. You can assign JSValues of course.
I see, that reference I used wasn’t complete.
Regards,
Ryan Joseph
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