Name
gl.ReadPixelsRaw -- read a block of pixels from the frame buffer
Synopsis
gl.ReadPixelsRaw(x, y, width, height, format, type, pixels)
Function
This does the same as gl.ReadPixels() but doesn't return the pixels in a table. Instead, the pixels are written directly to a memory block that has to be passed in pixels. This must be a memory buffer allocated by Hollywood's AllocMem() function and returned by GetMemPointer(). See Working with pointers for details on how to use memory pointers with Hollywood.

See gl.ReadPixels for a list of supported types for the format parameter.

Additionally, gl.ReadPixelsRaw() also allows you to define the data type that should be used when reading pixels from the frame buffer. type can assume the following values: #GL_UNSIGNED_BYTE, #GL_BYTE, #GL_BITMAP, #GL_UNSIGNED_SHORT, #GL_SHORT, #GL_UNSIGNED_INT, #GL_INT, or #GL_FLOAT. gl.ReadPixels() always uses #GL_FLOAT. With gl.ReadPixelsRaw() you can adjust this parameter to your specific needs.

See gl.ReadPixels for details.

Please consult an OpenGL reference manual for more information.

Inputs
x
specify the left coordinate of a rectangular block of pixels
y
specify the lower coordinate of a rectangular block of pixels
width
width of the pixel rectangle
height
height of the pixel rectangle
format
format of the pixel data (see above)
type
specifies the data type of the pixel data (see above)
pixels
pointer to a memory buffer to write the pixels to
Errors
#GL_INVALID_ENUM is generated if format or type is not an accepted value.

#GL_INVALID_VALUE is generated if either width or height is negative.

#GL_INVALID_OPERATION is generated if format is #GL_COLOR_INDEX and the color buffers store RGBA color components.

#GL_INVALID_OPERATION is generated if format is #GL_STENCIL_INDEX and there is no stencil buffer.

#GL_INVALID_OPERATION is generated if format is #GL_DEPTH_COMPONENT and there is no depth buffer.

#GL_INVALID_OPERATION is generated if gl.ReadPixels() is executed between the execution of gl.Begin() and the corresponding execution of gl.End().

Associated gets
gl.Get() with argument #GL_INDEX_MODE

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