
A
glAccum
Chapter 1
11
Each component value is divided by 2
n
-1, where n is the number of
bits allocated to each color component in the currently selected buffer.
The result is a floating-point value in the range [0, 1], which is
multiplied by value and added to the corresponding pixel component in
the accumulation buffer, thereby updating the accumulation buffer.
GL_LOAD
Similar to GL_ACCUM, except that the current value in the
accumulation buffer is not used in the calculation of the new value.
That is, the R, G, B, and A values from the currently selected buffer are
divided by 2
n
- 1, multiplied by value, and then stored in the
corresponding accumulation buffer cell, overwriting the current value.
GL_ADD
Adds value to each R, G, B, and A in the accumulation buffer.
GL_MULT
Multiplies each R, G, B, and A in the accumulation buffer by value and
returns the scaled component to its corresponding accumulation buffer
location.
GL_RETURN
Transfers accumulation buffer values to the color buffer or buffers
currently selected for writing. Each R, G, B, and A component is
multiplied by value, then multiplied by 2
n
- 1, clamped to the range [0,
2
n
- 1], and stored in the corresponding display buffer cell. The only
fragment operations that are applied to this transfer are pixel
ownership, scissor, dithering, and color writemasks.
To clear the accumulation buffer, call glClearAccum with R, G, B, and A values to set it
to, then call glClear with the accumulation buffer enabled.
Notes
Only pixels within the current scissor box are updated by a glAccum operation.
Errors
•
GL_INVALID_ENUM is generated if op is not an accepted value.
•
GL_INVALID_OPERATION is generated if there is no accumulation buffer.
•
GL_INVALID_OPERATION is generated if glAccum is executed between the
execution of glBegin and the corresponding execution of glEnd.
Associated Gets
glGet with argument GL_ACCUM_RED_BITS
glGet with argument GL_ACCUM_GREEN_BITS
glGet with argument GL_ACCUM_BLUE_BITS
glGet with argument GL_ACCUM_ALPHA_BITS
See Also
glBlendFunc,
glClear,
glClearAccum,
glCopyPixels,
glGet,
Содержание c3700 - Workstation
Страница 9: ...Chapter 1 9 1 A ...
Страница 12: ...A glAccum Chapter 1 12 glLogicOp glPixelStore glPixelTransfer glReadBuffer glReadPixels glScissor glStencilOp ...
Страница 18: ...A glArrayElement Chapter 1 18 glNormalPointer glTexCoordPointer glVertexPointer ...
Страница 19: ...Chapter 2 19 2 B ...
Страница 40: ...B gluBuild2DMipmaps Chapter 2 40 ...
Страница 41: ...Chapter 3 41 3 C ...
Страница 49: ...C glXChooseVisual Chapter 3 49 See Also glXCreateContext glXGetConfig ...
Страница 73: ...C glCopyPixels Chapter 3 73 glReadBuffer glReadPixels glStencilFunc ...
Страница 84: ...C glCopyTexSubImage2D Chapter 3 84 glTexParameter glTexSubImage1D glTexSubImage2D ...
Страница 93: ...Chapter 4 93 4 D ...
Страница 99: ...D glDeleteTextures Chapter 4 99 glTexImage1D glTexImage2D glTexParameter ...
Страница 127: ...Chapter 5 127 5 E ...
Страница 148: ...E glEvalPoint Chapter 5 148 ...
Страница 149: ...Chapter 6 149 6 F ...
Страница 161: ...Chapter 7 161 7 G ...
Страница 164: ...G glGenTextures Chapter 7 164 glTexImage1D glTexImage2D glTexParameter ...
Страница 185: ...G glGet Chapter 7 185 glGetTexGen glGetTexImage glGetTexLevelParameter glGetTexParameter glIsEnabled ...
Страница 207: ...G glGetPointer Chapter 7 207 glSelectBuffer glTexCoordPointer glVertexPointer ...
Страница 224: ...G glGetTexParameter Chapter 7 224 See Also glAreTexturesResident glPrioritizeTextures glTexParameter ...
Страница 225: ...Chapter 8 225 8 H ...
Страница 228: ...H glHint Chapter 8 228 ...
Страница 229: ...Chapter 9 229 9 I ...
Страница 248: ...I glIsTexture Chapter 9 248 ...
Страница 249: ...Chapter 10 249 10 L ...
Страница 256: ...L glLightModel Chapter 10 256 See Also glLight glMaterial ...
Страница 271: ...Chapter 11 271 11 M ...
Страница 291: ...Chapter 12 291 12 N ...
Страница 312: ...N gluNurbsSurface Chapter 12 312 ...
Страница 313: ...Chapter 13 313 13 O ...
Страница 317: ...Chapter 14 317 14 P ...
Страница 345: ...P glPolygonStipple Chapter 14 345 See Also glDrawPixels glLineStipple glPixelStore glPixelTransfer ...
Страница 360: ...P glPushName Chapter 14 360 See Also glInitNames glLoadName glRenderMode glSelectBuffer ...
Страница 362: ...P gluPwlCurve Chapter 14 362 ...
Страница 363: ...Chapter 15 363 15 Q ...
Страница 372: ...Q glXQueryVersion Chapter 15 372 glXQueryVersion ...
Страница 373: ...Chapter 16 373 16 R ...
Страница 390: ...R glRotate Chapter 16 390 ...
Страница 391: ...Chapter 17 391 17 S ...
Страница 397: ...S glScissor Chapter 17 397 See Also glEnable glViewport ...
Страница 409: ...Chapter 18 409 18 T ...
Страница 430: ...T glTexEnv Chapter 18 430 glCopyTexSubImage2D glTexImage1D glTexImage2D glTexParameter glTexSubImage1D glTexSubImage2D ...
Страница 448: ...T glTexImage3DEXT Chapter 18 448 glTexGen glTexImage1D glTexImage2D glTexParameter ...
Страница 457: ...T glTexSubImage1D Chapter 18 457 glTexImage2D glTexParameter glTexSubImage2D ...
Страница 465: ...T glTranslate Chapter 18 465 See Also glMatrixMode glMultMatrix glPushMatrix glScale ...
Страница 466: ...T glTranslate Chapter 18 466 ...
Страница 467: ...Chapter 19 467 19 U ...
Страница 469: ...U gluUnProject Chapter 19 469 See Also glGet gluProject ...
Страница 471: ...U glXUseXFont Chapter 19 471 See Also glBitmap glXMakeCurrent ...
Страница 472: ...U glXUseXFont Chapter 19 472 ...
Страница 473: ...Chapter 20 473 20 V ...
Страница 482: ...V glVisibilityBufferhp Chapter 20 482 ...
Страница 483: ...Chapter 21 483 21 W ...
Страница 486: ...W glXWaitX Chapter 21 486 ...