GreGetPageViewport: Difference between revisions

Latest revision as of 03:16, 24 January 2020

GreGetPageViewport loads the buffer indicated by prclViewport with the page viewport coordinates.

This function can be hooked by the presentation driver.

Simulation support: This function is simulated by a handling routine in the graphics engine.

Syntax

GreGetPageViewport(hdc, prclViewport, pInstance, lFunction)

Parameters

hdc (HDC) - input: Device context handle.
prclViewport (PRECTL) - input: Pointer to page viewport boundaries.
pInstance (PVOID) - input: Pointer to instance data.
lFunction (ULONG) - input: High-order WORD=flags; low-order WORD=NGreGetPageViewport.

Returns

fSuccess (BOOL) - returns

Return codes.

This function returns BOOLEAN (fSuccess).

TRUE Successful
FALSE Error

Possible Errors Detected: When an error is detected, the handling routine must call WinSetErrorInfo to post the condition. Error codes for conditions that the handling routine is expected to check include:

PMERR_HDC_BUSY
PMERR_INV_HDC

Refer to the "Error Explanations" section in the Presentation Manager Programming Reference for further explanation.

Sample

#define INCL_GRE_XFORMS
#include <os2.h>

HDC       hdc;           /*  Device context handle. */
PRECTL    prclViewport;  /*  Pointer to page viewport boundaries. */
PVOID     pInstance;     /*  Pointer to instance data. */
ULONG     lFunction;     /*  High-order WORD=flags; low-order WORD=NGreGetPageViewport. */
BOOL      fSuccess;      /*  Return codes. */

fSuccess = GreGetPageViewport(hdc, prclViewport, pInstance, lFunction);

@@ Line 1: / Line 1: @@
 GreGetPageViewport loads the buffer indicated by prclViewport with the page viewport coordinates.
 This function can be hooked by the presentation driver.
 ;Simulation support: This function is simulated by a handling routine in the graphics engine.
 == Syntax ==
-  GreGetPageViewport(hdc, prclViewport, pInstance, lFunction);
+  GreGetPageViewport(hdc, prclViewport, pInstance, lFunction)
 == Parameters ==
-;hdc (HDC) - input
+;hdc (HDC) - input:Device context handle.
-:Device context handle.
+;prclViewport (P[[RECTL]]) - input:Pointer to page viewport boundaries.
+;pInstance (PVOID) - input:Pointer to instance data.
-;prclViewport (PRECTL) - input
+;lFunction (ULONG) - input:High-order WORD=flags; low-order WORD=NGreGetPageViewport.
-:Pointer to page viewport boundaries.
-:This is a RECTL structure in device coordinates:
-::xLeft Minimum x-coordinate of viewport
-::yBottom Minimum y-coordinate
-::xRight Maximum x-coordinate of viewport
-::yTop Maximum y-coordinate
-:Boundaries are inclusive at the bottom-left corner, and exclusive at the top-right corner.
-;pInstance (PVOID) - input
-:Pointer to instance data.
-;lFunction (ULONG) - input
-:High-order WORD=flags; low-order WORD=NGreGetPageViewport.
 == Returns ==
-;fSuccess (BOOL) - returns
+;fSuccess (BOOL) - returns:Return codes.
-:Return codes.
+:This function returns BOOLEAN (fSuccess).
+:*TRUE Successful
-:This function returns BOOLEAN (fSuccess).
+:*FALSE Error
+:Possible Errors Detected: When an error is detected, the handling routine must call WinSetErrorInfo to post the condition. Error codes for conditions that the handling routine is expected to check include:
-:*TRUE Successful
+:*PMERR_HDC_BUSY
-:*FALSE Error
+:*PMERR_INV_HDC
+:Refer to the "Error Explanations" section in the ''Presentation Manager Programming Reference'' for further explanation.
-:Possible Errors Detected:   When an error is detected, the handling routine must call WinSetErrorInfo to post the condition. Error codes for conditions that the handling routine is expected to check include:
-:*PMERR_HDC_BUSY
-:*PMERR_INV_HDC
-:Refer to the "Error Explanations" section in the Presentation Manager Programming Reference for further explanation.
 == Sample ==
@@ Line 58: / Line 36: @@
 fSuccess = GreGetPageViewport(hdc, prclViewport, pInstance, lFunction);
 </pre>
 [[Category:Gre]]