Function initTestTexture

Source/3rdParty/bgfx/src/renderer_gl.cpp:1613–1671

	}

	GLenum initTestTexture(TextureFormat::Enum _format, bool _srgb, bool _mipmaps, bool _array, GLsizei _dim)
	{
		const TextureFormatInfo& tfi = s_textureFormat[_format];
		GLenum internalFmt = _srgb
			? tfi.m_internalFmtSrgb
			: tfi.m_internalFmt
			;
		GLenum fmt = _srgb
			? tfi.m_fmtSrgb
			: tfi.m_fmt
			;

		GLsizei bpp  = bimg::getBitsPerPixel(bimg::TextureFormat::Enum(_format) );
		GLsizei size = (_dim*_dim*bpp)/8;
		void* data = NULL;

		if (bimg::isDepth(bimg::TextureFormat::Enum(_format) ) )
		{
			_srgb    = false;
			_mipmaps = false;
			_array   = false;
		}
		else
		{
			data = bx::alignPtr(BX_STACK_ALLOC(size+16), 0, 16);
		}

		flushGlError();
		GLenum err = 0;

		const GLenum target = _array
			? GL_TEXTURE_2D_ARRAY
			: GL_TEXTURE_2D
			;

		if (bimg::isCompressed(bimg::TextureFormat::Enum(_format) ) )
		{
			for (uint32_t ii = 0, dim = _dim; ii < (_mipmaps ? 5u : 1u) && 0 == err; ++ii, dim >>= 1)
			{
				dim = bx::uint32_max(1, dim);
				uint32_t block = bx::uint32_max(4, dim);
				size = (block*block*bpp)/8;
				compressedTexImage(target, ii, internalFmt, dim, dim, 0, 0, size, data);
				err |= getGlError();
			}
		}
		else
		{
			for (uint32_t ii = 0, dim = _dim; ii < (_mipmaps ? 5u : 1u) && 0 == err; ++ii, dim >>= 1)
			{
				dim = bx::uint32_max(1, dim);
				size = (dim*dim*bpp)/8;
				texImage(target, 0, ii, internalFmt, dim, dim, 0, 0, fmt, tfi.m_type, data);
				err |= getGlError();
			}
		}

		return err;