GLVIEWPORT(3G)

✨ NAME ✨

okay bestie, welcome to GLVIEWPORT(3G) — the manual page for glViewport, and its whole personality is: set the viewport. That’s the job, that’s the name, no cap 💅

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💖 C SPECIFICATION 💖

the exact signature vibe, preserved character-for-character:

       void glViewport( GLint x,
                        GLint y,
                        GLsizei width,
                        GLsizei height )

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🎀 PARAMETERS 🎀

• x, y — specify the lower left corner of the viewport rectangle, in pixels. The initial value is (0,0). iconic starting point, honestly 🫶
• width, height — specify the width and height of the viewport. When a GL context is first attached to a window, width and height are set to the dimensions of that window. slay, automatic sizing ✨

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🦋 DESCRIPTION 🦋

so glViewport specifies the affine transformation of x and y from normalized device coordinates to window coordinates. Let (xnd, ynd) be normalized device coordinates. Then the window coordinates (xw, yw) are computed as follows — and yes, I’m keeping the printed math exactly as it appears:

                                 xw=(xnd+1)⎝_____⎠+x

                                 yw=(ynd+1)⎝______⎠+y

Viewport width and height are silently clamped to a range that depends on the implementation. To query this range, call glGet with argument GL_MAX_VIEWPORT_DIMS. lowkey important, bestie 🔍

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💀 ERRORS 💀

• GL_INVALID_VALUE is generated if either width or height is negative. not the negative dimensions era, pls 😭
• GL_INVALID_OPERATION is generated if glViewport is executed between the execution of glBegin and the corresponding execution of glEnd. read the room, bestie 💀

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🔥 ASSOCIATED GETS 🔥

• glGet with argument GL_VIEWPORT
• glGet with argument GL_MAX_VIEWPORT_DIMS

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🌈 SEE ALSO 🌈

• glDepthRange(3G)

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okay that’s the whole page, bestie — the footer is just GLVIEWPORT(3G), and there’s no extra source/version/date line in the original, so I’m not inventing one. catch u in the next man page, mwah 🫶💖