GLCLIENTACTIVETEXTUREARB(3G)

✨ GLCLIENTACTIVETEXTUREARB ✨

okay bestie, listen up 💖 this one lives in the 3G manual section, and it's literally the vibe-setter for which texture unit your client-side vertex arrays are about to get all up in. No cap.

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🌸 NAME 🌸

glClientActiveTextureARB — pick the active texture unit, bestie 👑

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🎀 C SPECIFICATION 🎀

void glClientActiveTextureARB( GLenum texture )

like, that's it. one arg. one job. she's simple but she's iconic 💅

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🦋 PARAMETERS 🦋

• texture — tells the universe which texture unit is getting the spotlight ✨. The number of texture units is implementation dependent, but it's gotta be at least two, periodt. So texture must be one of GL_TEXTUREi_ARB where 0 ≤ i < GL_MAX_TEXTURE_UNITS_ARB, and GL_MAX_TEXTURE_UNITS_ARB is itself an implementation-dependent value 🙈. The initial value is GL_TEXTURE0_ARB.

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🌈 DESCRIPTION 🌈

So here's the tea 🍓: glClientActiveTextureARB selects which vertex array client state parameters get modified by glTexCoordPointer, and which get enabled or disabled with glEnableClientState or glDisableClientState respectively — but only when you call those with a parameter of GL_TEXTURE_COORD_ARRAY. That's the whole plot. She's the main character that decides whose texcoord array we're talking about 💫

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💜 NOTES 💜

ngl, there's a whole prerequisite here 👇

glClientActiveTextureARB is supported only if GL_ARB_multitexture shows up in the string returned by glGetString when you call it with the argument GL_EXTENSIONS. So check that vibe first, fr fr 🔍

Also, fun fact for the group chat: glClientActiveTextureARB sets GL_CLIENT_ACTIVE_TEXTURE_ARB to the active texture unit. she literally updates the state, iconic behavior 👑

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💀 ERRORS 💀

• GL_INVALID_ENUM gets generated if texture is not one of GL_TEXTUREi_ARB, where 0 ≤ i < GL_MAX_TEXTURE_UNITS_ARB.

so like, don't pass a random number and expect her to be chill about it 😭 she will absolutely throw hands with that enum.

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👑 SEE ALSO 👑

• glActiveTextureARB(3G)
• glDisableClientState(3G)
• glEnableClientState(3G)
• glMultiTexCoordARB(3G)
• glTexCoordPointer(3G)

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🫶 reminder bestie: every flag, every value, every default in this page is exactly what the original said. the vibe is new, the facts are untouched. don't come for me about accuracy, I ate and left no crumbs 💅

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and that's the page!! 🌟 shoutout to the 3G manual for hosting her, and to the page itself, GLCLIENTACTIVETEXTUREARB(3G) — she's been in the source tree forever and she still slays. mwah 🎀💖✨