Unit Neslib.Ooogles

You must call this procdure After you have created and activated your OpenGL context. This is needed to emulate OpenGL-ES on OpenGL platforms. If your application uses multiple contexts, you must call InitOoogles once for each context (after making it current).

OpenGL error codes

Values

• NoError = GL_NO_ERROR: No error has been recorded.
• InvalidEnum = GL_INVALID_ENUM: An unacceptable value is specified for an enumerated argument. The offending command is ignored and has no other side effect than to set the error flag.
• InvalidValue = GL_INVALID_VALUE: A numeric argument is out of range. The offending command is ignored and has no other side effect than to set the error flag.
• InvalidOperation = GL_INVALID_OPERATION: The specified operation is not allowed in the current state. The offending command is ignored and has no other side effect than to set the error flag.
• InvalidFramebufferOperation = GL_INVALID_FRAMEBUFFER_OPERATION: The command is trying to render to or read from the framebuffer while the currently bound framebuffer is not framebuffer complete. The offending command is ignored and has no other side effect than to set the error flag.
• OutOfMemory = GL_OUT_OF_MEMORY: There is not enough memory left to execute the command. The state of the GL is undefined, except for the state of the error flags, after this error is recorded.

A buffer to clear using gl.Clear.

Values

• _Reserved = 0: Reserved (only here for API compatibility)
• Depth = 8: To clear the depth buffer
• Stencil = 10: To clear the stencil buffer
• Color = 14: To clear the color buffer

A set of buffers to clear using gl.Clear.

The type of a shader

Values

• Vertex = GL_VERTEX_SHADER: A vertex shader
• Fragment = GL_FRAGMENT_SHADER: A fragment shader

Supported data types

Values

• Byte = GL_BYTE: 8-bit signed integer. Corresponds to Delphi's Int8 or ShortInt.
• Short = GL_SHORT: 16-bit signed integer Corresponds to Delphi's Int16 or SmallInt.
• Int = GL_INT: 32-bit signed integer Corresponds to Delphi's Int32 or Integer.
• Float = GL_FLOAT: 32-bit floating-point value. Corresponds to Delphi's Single type.
• UnsignedByte = GL_UNSIGNED_BYTE: 8-bit unsigned integer. Corresponds to Delphi's UInt8 or Byte.
• UnsignedShort = GL_UNSIGNED_SHORT: 16-bit unsigned integer. Corresponds to Delphi's UInt16 or Word.
• UnsignedInt = GL_UNSIGNED_INT: 32-bit unsigned integer. Corresponds to Delphi's UInt32 or Cardinal.

Supported primitive types

Values

• Points = GL_POINTS: Single points.
• Lines = GL_LINES: Single lines.
• LineStrip = GL_LINE_STRIP: Connected lines.
• LineLoop = GL_LINE_LOOP: Connected lines, closed to form a polygon.
• Triangles = GL_TRIANGLES: Single triangles.
• TriangleStrip = GL_TRIANGLE_STRIP: A strip of triangles.
• TriangleFan = GL_TRIANGLE_FAN: A fan of triangles.

Supported buffer types

Values

• Vertex = GL_ARRAY_BUFFER: A vertex buffer (aka array buffer). Contains an array of vertices.
• Index = GL_ELEMENT_ARRAY_BUFFER: An index buffer (aka element array buffer). Contains an array of indices to vertices.

Hints how a buffer object's data is accessed.

Values

• StaticDraw = GL_STATIC_DRAW: The data stored in a buffer will be modified once and used many times.
• StreamDraw = GL_STREAM_DRAW: The data stored in a buffer will be modified once and used at most a few times.
• DynamicDraw = GL_DYNAMIC_DRAW: The data stored in a buffer will be modified repeatedly and used many times.

Supported types of indices

Values

• UnsignedByte = GL_UNSIGNED_BYTE: 8-bit unsigned integer. Corresponds to Delphi's UInt8 or Byte.
• UnsignedShort = GL_UNSIGNED_SHORT: 16-bit unsigned integer. Corresponds to Delphi's UInt16 or Word.

Supported texture types

Values

• TwoD = GL_TEXTURE_2D: A 2D texture
• CubeMap = GL_TEXTURE_CUBE_MAP: A cube map texture

Supported pixel formats

Values

• Alpha = GL_ALPHA: Each element is a single alpha component. The GL converts it to floating point and assembles it into an RGBA element by attaching 0 for red, green, and blue. Each component is then clamped to the range [0,1].
• RGB = GL_RGB: Each element is an RGB triple. The GL converts it to floating point and assembles it into an RGBA element by attaching 1 for alpha. Each component is then clamped to the range [0,1].
• RGBA = GL_RGBA: Each element contains all four components. The GL converts it to floating point, then each component is clamped to the range [0,1].
• Luminance = GL_LUMINANCE: Each element is a single luminance value. The GL converts it to floating point, then assembles it into an RGBA element by replicating the luminance value three times for red, green, and blue and attaching 1 for alpha. Each component is then clamped to the range [0,1].
• LuminanceAlpha = GL_LUMINANCE_ALPHA: Each element is a luminance/alpha pair. The GL converts it to floating point, then assembles it into an RGBA element by replicating the luminance value three times for red, green, and blue. Each component is then clamped to the range [0,1].

Target indices for the six sides of a cube texture:

• 0: Face in positive X direction

• 1: Face in negative X direction

• 2: Face in positive Y direction

• 3: Face in negative Y direction

• 4: Face in positive Z direction

• 5: Face in negative Z direction

Supported pixel data types

Values

• UnsignedByte = GL_UNSIGNED_BYTE: Each byte is interpreted as one color component (red, green, blue or alpha). When converted to floating point, the value is divided by 255.
• UnsignedShort565 = GL_UNSIGNED_SHORT_5_6_5: A single 16-bit integer contains 5 bits for the red component, 6 bits for the green component and 5 bits for the blue component. When converted to floating point, the red and blue components are divided by 31 and the green component is divided by 63.
• UnsignedShort4444 = GL_UNSIGNED_SHORT_4_4_4_4: A single 16-bit integer contains all components, with 4 bits for each component. When converted to floating point, every component is divided by 15.
• UnsignedShort5551 = GL_UNSIGNED_SHORT_5_5_5_1: A single 16-bit integer contains all components, with 5 bits for the red, green and blue components, and 1 bit for the alpha component. When converted to floating point, the red, green and blue components are divided by 31 and the alpha component is used as-is.

Texture magnification filters

Values

• Nearest = GL_NEAREST: Returns the value of the texture element that is nearest (in Manhattan distance) to the center of the pixel being textured. This is usually the fastest method.
• Linear = GL_LINEAR: Returns the weighted average of the four texture elements that are closest to the center of the pixel being textured. This usually provides better quality.

Texture minification filters

Values

• Nearest = GL_NEAREST: Returns the value of the texture element that is nearest (in Manhattan distance) to the center of the pixel being textured. This is usually the fastest method.
• Linear = GL_LINEAR: Returns the weighted average of the four texture elements that are closest to the center of the pixel being textured. This usually provides better quality than Nearest.
• NearestMipmapNearest = GL_NEAREST_MIPMAP_NEAREST: Chooses the mipmap that most closely matches the size of the pixel being textured and uses the Nearest criterion (the texture element nearest to the center of the pixel) to produce a texture value. This is usually the fastest method when using mipmapping.
• LinearMipmapNearest = GL_LINEAR_MIPMAP_NEAREST: Chooses the mipmap that most closely matches the size of the pixel being textured and uses the Linear criterion (a weighted average of the four texture elements that are closest to the center of the pixel) to produce a texture value.
• NearestMipmapLinear = GL_NEAREST_MIPMAP_LINEAR: Chooses the two mipmaps that most closely match the size of the pixel being textured and uses the Nearest criterion (the texture element nearest to the center of the pixel) to produce a texture value from each mipmap. The final texture value is a weighted average of those two values.
• LinearMipmapLinear = GL_LINEAR_MIPMAP_LINEAR: Chooses the two mipmaps that most closely match the size of the pixel being textured and uses the Linear criterion (a weighted average of the four texture elements that are closest to the center of the pixel) to produce a texture value from each mipmap. The final texture value is a weighted average of those two values. This is usually the slowest (but highest quality) method when using mipmapping.

Texture wrapping modes

Values

• NormalRepeat = GL_REPEAT: Repeats the texture. Causes the integer part of the texture coordinate to be ignored; the GL uses only the fractional part, thereby creating a repeating pattern.
• MirroredRepeat = GL_MIRRORED_REPEAT: Repeats and mirrors the texture. Causes the final texture coordinate (Dst) to be set to the fractional part of the original texture coordinate (Src) if the integer part of Src is even; if the integer part of Src is odd, then Dst is set to 1 - Frac(Src), where Frac(Src) represents the fractional part of Src.
• ClampToEdge = GL_CLAMP_TO_EDGE: Clamps the texture to its edges. Causes the texture coordinate to be clamped to the size of the texture in the direction of clamping.

Mipmap hinting options, as used by TGLTexture.MipmapHint

Values

• Fastest = GL_FASTEST: The most efficient option should be chosen.
• Nicest = GL_NICEST: The most correct, or highest quality, option should be chosen.
• DontCare = GL_DONT_CARE: No preference.

OpenGL capabilities than can be enabled and disabled (using gl.Enable and gl.Disable)

Values

• Blend = GL_BLEND: If enabled, blend the computed fragment color values with the values in the color buffers.

  See also

  gl.BlendFunc.

  Specify pixel arithmetic using blend functions.

• CullFace = GL_CULL_FACE: If enabled, cull polygons based on their winding in window coordinates.

  See also

  gl.CullFace.

  Specify whether front- or back-facing polygons can be culled.

• DepthTest = GL_DEPTH_TEST: If enabled, do depth comparisons and update the depth buffer. Note that even if the depth buffer exists and the depth mask is non-zero, the depth buffer is not updated if the depth test is disabled.

  See also

  and gl.DepthRangef.

  Specify the value used for depth buffer comparisons.

• Dither = GL_DITHER: If enabled, dither color components or indices before they are written to the color buffer.
• PolygonOffsetFill = GL_POLYGON_OFFSET_FILL: If enabled, an offset is added to depth values of a polygon's fragments produced by rasterization.

  See also

  gl.PolygonOffset.

  Set the scale and units used to calculate polygon depth values.

• SampleAlphaToCoverage = GL_SAMPLE_ALPHA_TO_COVERAGE: If enabled, compute a temporary coverage value where each bit is determined by the alpha value at the corresponding sample location. The temporary coverage value is then ANDed with the fragment coverage value.
• SampleCoverage = GL_SAMPLE_COVERAGE: If enabled, the fragment's coverage is ANDed with the temporary coverage value.

  See also

  gl.SampleCoverage.

  Specify multisample coverage parameters.

• ScissorTest = GL_SCISSOR_TEST: If enabled, discard fragments that are outside the scissor rectangle.

  See also

  gl.Scissor.

  Define the scissor box.

• StencilTest = GL_STENCIL_TEST: If enabled, do stencil testing and update the stencil buffer.

  See also

  and gl.StencilOp.

  Set front and back function and reference value for stencil testing.

Faces used for culling and stencilling.

Values

• Front = GL_FRONT: Front-facing polygons are culled.
• Back = GL_BACK: Back-facing polygons are culled (the default).
• FrontAndBack = GL_FRONT_AND_BACK: Front- and back-facing polygons are culled.

Specifies the orientation of front-facing polygons, as used by gl.FrontFace.

Values

• Clockwise = GL_CW: Clockwise winding
• CounterClockwise = GL_CCW: Counter-clockwise winding (default)

Pixel storage modes, as used by gl.PixelStore.

Values

• PackAlignment = GL_PACK_ALIGNMENT: Specifies the packing of pixel data downloading from the GPU into client memory.
• UnpackAlignment = GL_UNPACK_ALIGNMENT: Specifies the packing of pixel data when uploading from client memory to the GPU.

Allowed values for TGLPixelStorage mode, as used by gl.PixelStore.

Values

• One = 1: Pixel data is aligned on a byte boundary
• Two = 2: Pixel data is aligned on 2-byte boundary
• Four = 4: Pixel data is aligned on 4-byte boundary
• Eight = 8: Pixel data is aligned on 8-byte boundary

Blend functions as used by gl.BlendFunc and gl.BlendFuncSeparate. In the descriptions of the items, the following terms are used:

• SColor: source color (R, G and B values)

• SAlpha: source alpha

• DColor: destination color

• DAlpha: destination alpha

• RColor: resulting color

• RAlpha: resulting alpha

• CColor: constant color, as specified using gl.BlendColor

• CAlpha: constant alpha, as specified using gl.BlendColor

Values

• Zero = GL_ZERO: RColor = 0, RAlpha = 0
• One = GL_ONE: RColor = 1, RAlpha = 1
• SrcColor = GL_SRC_COLOR: RColor = SColor, RAlpha = SAlpha
• OneMinusSrcColor = GL_ONE_MINUS_SRC_COLOR: RColor = 1 - SColor, RAlpha = 1 - SAlpha
• DstColor = GL_DST_COLOR: RColor = DColor, RAlpha = DAlpha
• OneMinusDstColor = GL_ONE_MINUS_DST_COLOR: RColor = 1 - DColor, RAlpha = 1 - DAlpha
• SrcAlpha = GL_SRC_ALPHA: RColor = SAlpha, RAlpha = SAlpha
• OneMinusSrcAlpha = GL_ONE_MINUS_SRC_ALPHA: RColor = 1 - SAlpha, RAlpha = 1 - SAlpha
• DstAlpha = GL_DST_ALPHA: RColor = DAlpha, RAlpha = DAlpha
• OneMinusDstAlpha = GL_ONE_MINUS_DST_ALPHA: RColor = 1 - DAlpha, RAlpha = 1 - DAlpha
• ConstantColor = GL_CONSTANT_COLOR: RColor = CColor, RAlpha = CAlpha
• OneMinusConstantColor = GL_ONE_MINUS_CONSTANT_COLOR: RColor = 1 - CColor, RAlpha = 1 - CAlpha
• ConstantAlpha = GL_CONSTANT_ALPHA: RColor = CAlpha, RAlpha = CAlpha
• OneMinusConstantAlpha = GL_ONE_MINUS_CONSTANT_ALPHA: RColor = 1 - CAlpha, RAlpha = 1 - CAlpha
• SrcAlphaSaturate = GL_SRC_ALPHA_SATURATE: RColor = Min(SAlpha, 1 - DAlpha), RAlpha = 1

Blend equations as used by gl.BlendEquation and gl.BlendEquationSeparate.

Values

• Add = GL_FUNC_ADD: Result = (SrcColor * SrcWeigth) + (DstColor * DstWeight)
• Subtract = GL_FUNC_SUBTRACT: Result = (SrcColor * SrcWeigth) - (DstColor * DstWeight)
• ReverseSubtract = GL_FUNC_REVERSE_SUBTRACT: Result = (DstColor * DstWeight) - (SrcColor * SrcWeigth)

Compare functions as used by gl.StencilFunc and gl.DepthFunc.

Values

• Never = GL_NEVER: The function always fails.
• Less = GL_LESS: For stencil operations, the function passes if (Ref and Mask) < (Stencil and Mask). For depth operations, the function passes if the incoming depth value is less than the stored depth value.
• LessOrEqual = GL_LEQUAL: For stencil operations, the function passes if (Ref and Mask) <= (Stencil and Mask). For depth operations, the function passes if the incoming depth value is less than or equal to the stored depth value.
• Greater = GL_GREATER: For stencil operations, the function passes if (Ref and Mask) > (Stencil and Mask). For depth operations, the function passes if the incoming depth value is greater than the stored depth value.
• GreaterOrEqual = GL_GEQUAL: For stencil operations, the function passes if (Ref and Mask) >= (Stencil and Mask). For depth operations, the function passes if the incoming depth value is greater than or equal to the stored depth value.
• Equal = GL_EQUAL: For stencil operations, the function passes if (Ref and Mask) = (Stencil and Mask). For depth operations, the function passes if the incoming depth value is equal to the stored depth value.
• NotEqual = GL_NOTEQUAL: For stencil operations, the function passes if (Ref and Mask) <> (Stencil and Mask). For depth operations, the function passes if the incoming depth value is not equal to the stored depth value.
• Always = GL_ALWAYS: The function always passes.

Stencil operations as used by gl.StencilOp.

Values

• Keep = GL_KEEP: Keeps the current value.
• Zero = GL_ZERO: Sets the stencil buffer value to 0.
• Replace = GL_REPLACE: Sets the stencil buffer value to ARef, as specified by gl.StencilFunc.
• Increment = GL_INCR: Increments the current stencil buffer value. Clamps to the maximum representable unsigned value.
• IncrementAndWrap = GL_INCR_WRAP: Increments the current stencil buffer value. Wraps stencil buffer value to zero when incrementing the maximum representable unsigned value.
• Decrement = GL_DECR: Decrements the current stencil buffer value. Clamps to 0.
• DecrementAndWrap = GL_DECR_WRAP: Decrements the current stencil buffer value. Wraps stencil buffer value to the maximum representable unsigned value when decrementing a stencil buffer value of zero.
• Invert = GL_INVERT: Bitwise inverts the current stencil buffer value.

Specifies the color-renderable, depth-renderable, or stencil-renderable format of a TGLRenderbuffer.

Values

• RGBA4 = GL_RGBA4: Color format with alpha support, using 4 bits per component (red, green, blue and alpha)
• RGB565 = GL_RGB565: Color format without alpha support, using 5 bits for the red and blue components and 6 bits for the green component.
• RGB5_A1 = GL_RGB5_A1: Color format with alpha support, using 5 bits for each color component (red, green and blue) and 1 bit for the alpha component.
• Depth16 = GL_DEPTH_COMPONENT16: 16-bit depth format
• Stencil8 = GL_STENCIL_INDEX8: 9-bit stencil format

Completeness status of a TGLFramebuffer.

Values

• Complete = GL_FRAMEBUFFER_COMPLETE: The framebuffer is complete
• IncompleteAttachment = GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT: Not all framebuffer attachment points are framebuffer attachment complete. This means that at least one attachment point with a renderbuffer or texture attached has its attached object no longer in existence or has an attached image with a width or height of zero, or the color attachment point has a non-color-renderable image attached, or the depth attachment point has a non-depth-renderable image attached, or the stencil attachment point has a non-stencil-renderable image attached.
• IncompleteDimensions = GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS_EXT: Not all attached images have the same width and height.
• MissingAttachment = GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT: No images are attached to the framebuffer.
• Unsupported = GL_FRAMEBUFFER_UNSUPPORTED: The combination of internal formats of the attached images violates an implementation-dependent set of restrictions.

Attachment points of a TGLFramebuffer

Values

• Color = GL_COLOR_ATTACHMENT0: Attachment point for a color buffer
• Depth = GL_DEPTH_ATTACHMENT: Attachment point for a depth buffer
• Stencil = GL_STENCIL_ATTACHMENT: Attachment point for a stencil buffer

Types of objects attached to a TGLFramebuffer

Values

• None = GL_NONE: No renderbuffer or texture is attached.
• RenderBuffer = GL_RENDERBUFFER: The attachment is a renderbuffer
• Texture = GL_TEXTURE: The attachment is a texture

Supported data types for attributes

Values

• Float = GL_FLOAT: Single-precision floating-point type. Corresponds to Delphi's Single type.
• Vector2 = GL_FLOAT_VEC2: A vector of 2 floats. Corresponds to FastMath's TVector2 type.
• Vector3 = GL_FLOAT_VEC3: A vector of 3 floats. Corresponds to FastMath's TVector3 type.
• Vector4 = GL_FLOAT_VEC4: A vector of 4 floats. Corresponds to FastMath's TVector4 type.
• Matrix2 = GL_FLOAT_MAT2: A 2x2 matrix of floats. Corresponds to FastMath's TMatrix2 type.
• Matrix3 = GL_FLOAT_MAT3: A 3x3 matrix of floats. Corresponds to FastMath's TMatrix3 type.
• Matrix4 = GL_FLOAT_MAT4: A 4x4 matrix of floats. Corresponds to FastMath's TMatrix4 type.

Supported data types for uniforms

Values

• Float = GL_FLOAT: Single-precision floating-point type. Corresponds to Delphi's Single type.
• Vector2 = GL_FLOAT_VEC2: A vector of 2 floats. Corresponds to FastMath's TVector2 type.
• Vector3 = GL_FLOAT_VEC3: A vector of 3 floats. Corresponds to FastMath's TVector3 type.
• Vector4 = GL_FLOAT_VEC4: A vector of 4 floats. Corresponds to FastMath's TVector4 type.
• Int = GL_INT: 32-bit integer type. Corresponds to Delphi's Integer type.
• IVector2 = GL_INT_VEC2: A vector of 2 integers. Corresponds to FastMath's TIVector2 type.
• IVector3 = GL_INT_VEC3: A vector of 3 integers. Corresponds to FastMath's TIVector3 type.
• IVector4 = GL_INT_VEC4: A vector of 4 integers. Corresponds to FastMath's TIVector4 type.
• Bool = GL_BOOL: Boolean type.
• BVector2 = GL_BOOL_VEC2: A vector of 2 booleans.
• BVector3 = GL_BOOL_VEC3: A vector of 3 booleans.
• BVector4 = GL_BOOL_VEC4: A vector of 4 booleans.
• Matrix2 = GL_FLOAT_MAT2: A 2x2 matrix of floats. Corresponds to FastMath's TMatrix2 type.
• Matrix3 = GL_FLOAT_MAT3: A 3x3 matrix of floats. Corresponds to FastMath's TMatrix3 type.
• Matrix4 = GL_FLOAT_MAT4: A 4x4 matrix of floats. Corresponds to FastMath's TMatrix4 type.
• Sampler2D = GL_SAMPLER_2D: A 2D texture sampler
• SamplerCube = GL_SAMPLER_CUBE: A cubetexture sampler