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NAVTOR SDK
v.3.0
Software Development Kit for fast and efficient development of ECDIS, ECS and generic marine applications
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Go to the documentation of this file. 1 #ifndef SDK_GL2D_CANVAS_INTERFACE_H_
11 #define SDK_GL2D_CANVAS_INTERFACE_H_
16 #include <base/inc/sdk_component_base.h>
22 #include <visualizationlayer/inc/vis_const.h>
24 #include "./gl2d_canvas_func/gl2d_canvas_utils_interface.h"
25 #include "./gl2d_canvas_func/gl2d_canvas_projection_func_interface.h"
26 #include "./gl2d_canvas_func/gl2d_canvas_palette_func_interface.h"
27 #include "./gl2d_canvas_func/gl2d_canvas_radar_image_func_interface.h"
28 #include "./gl2d_canvas_func/gl2d_canvas_filled_circles_func_interface.h"
29 #include "./gl2d_canvas_func/gl2d_canvas_pattern_func_interface.h"
30 #include "./gl2d_canvas_func/gl2d_canvas_textbox_func_interface.h"
31 #include "./gl2d_canvas_func/gl2d_canvas_bordered_latin1_text_func_interface.h"
32 #include "./gl2d_canvas_func/gl2d_canvas_latin1_text_func_interface.h"
33 #include "./gl2d_canvas_func/gl2d_canvas_text_func_interface.h"
34 #include "./gl2d_canvas_func/gl2d_canvas_line_mark_func_interface.h"
35 #include "./gl2d_canvas_func/gl2d_canvas_sprites_func_interface.h"
36 #include "./gl2d_canvas_func/gl2d_canvas_textured_line_func_interface.h"
37 #include "./gl2d_canvas_func/gl2d_canvas_texture_func_interface.h"
38 #include "./gl2d_canvas_func/gl2d_canvas_light_source_func_interface.h"
39 #include "./gl2d_canvas_func/gl2d_canvas_mesh_func_interface.h"
40 #include "./gl2d_canvas_func/gl2d_canvas_line_func_interface.h"
45 #include "gl2d_textures_storage_interface.h"
48 #include "gl2d_thread_interface.h"
52 #if defined (SDK_CC_GCC)
53 # pragma GCC diagnostic push
54 # pragma GCC diagnostic ignored "-Wextra"
57 SDK_GL2D_BEGIN_NAMESPACE
90 kGL2DCanvasPropertyID_DPI = 1,
229 kGL2DCanvasPropertyID_Private = 1000,
237 kGL2DPlatformType_WGL = 0,
240 kGL2DPlatformType_EGL = 1,
243 kGL2DPlatformType_Mesa = 2,
246 kGL2DPlatformType_GLX = 3,
252 kGL2DPlatformType_ExternallyCreated = 4,
263 kGL2DPlatformType_ExternallyManaged = 5,
270 kGL2DCanvasType_Auto = 0,
271 kGL2DCanvasType_OpenGL = 1,
272 kGL2DCanvasType_OpenGL_ES2 = 2,
280 kGL2DDeviceType_Unknown = 0x00000000L,
284 kGL2DDeviceType_Generic_Desktop = 0x00000001L,
286 kGL2DDeviceType_Generic_Android = 0x00000002L,
288 kGL2DDeviceType_Generic_iOS = 0x00000003L,
292 kGL2DDeviceType_iMX6 = 0x00001000L,
298 kGL2DDeviceType_BSA_Laptop = 0x80000000L,
301 kGL2DDeviceType_DesktopLinux_TestDevice = 0x80000001L,
304 kGL2DDeviceType_iMX6_TestDevice = 0x80000002L,
307 kGL2DDeviceType_Android_TestDevice_SGS3 = 0x80000003L,
310 kGL2DDeviceType_Android_TestDevice_XperiaZ = 0x80000004L,
313 kGL2DDeviceType_Android_TestDevice_MediaPadM5Pro = 0x80000005L,
321 kGL2DCacheType_None = 0x00000000UL,
324 kGL2DCacheType_SymbolsTextures = 0x00000001UL,
326 kGL2DCacheType_CharMapTextures = 0x00000002UL,
328 kGL2DCacheType_GLBuffers = 0x00000004UL,
331 kGL2DCacheType_All = kGL2DCacheType_SymbolsTextures |
332 kGL2DCacheType_CharMapTextures |
333 kGL2DCacheType_GLBuffers,
359 kGL2DCreateCanvasSettingIDs_GlLibHandle = 3,
414 kGL2DCreateCanvasSettingIDs_DebugContext = 1000,
416 typedef SDKPropertiesSP IGL2DCreateCanvasSettingsSP;
436 public IGL2DCanvasUtils,
437 public IGL2DCanvasProjectionFunc,
438 public IGL2DCanvasPaletteFunc,
439 public IGL2DCanvasRadarImageFunc,
440 public IGL2DCanvasFilledCirclesFunc,
441 public IGL2DCanvasPatternFunc,
442 public IGL2DCanvasTextBoxFunc,
443 public IGL2DCanvasBorderedLatin1TextFunc,
444 public IGL2DCanvasLatin1TextFunc,
445 public IGL2DCanvasTextFunc,
446 public IGL2DCanvasLineMarkFunc,
447 public IGL2DCanvasSpritesFunc,
448 public IGL2DCanvasTexturedLineFunc,
449 public IGL2DCanvasTextureFunc,
450 public IGL2DCanvasLightSourceFunc,
451 public IGL2DCanvasMeshFunc,
452 public IGL2DCanvasLineFunc
456 virtual void SDK_CALLTYPE
Dump()
const throw() = 0;
459 virtual IGL2DFactorySP SDK_CALLTYPE
GetParent()
const throw() = 0;
461 virtual IGL2DFontsStorageSP SDK_CALLTYPE
GetFontsStorage()
const throw() = 0;
463 virtual IGL2DCanvasDrawLockSP SDK_CALLTYPE
GetDrawLock()
const throw() = 0;
473 virtual IGL2DCapsSP SDK_CALLTYPE
GetCaps()
const throw() = 0;
475 virtual IGL2DStatsSP SDK_CALLTYPE
GetStats()
const throw() = 0;
482 const IGL2DCapsSP caps =
GetCaps();
483 return caps ? caps->IsCanvasOperationSupported(type) :
false;
520 const bool& release_internal_contexts)
throw() = 0;
539 GlCtx& resource_ctx) const throw() = 0;
545 GlCtx& drawing_ctx) const throw() = 0;
571 const SDKUInt32& cache_id) const throw() = 0;
577 const SDKUInt32& cache_id, const SDKUInt64& size_to_reduce) const throw() = 0;
581 IGL2DTexturesStorageSP& textures_storage) const throw() = 0;
593 const IGL2DTextureSP& output_texture,
594 const SDKMatrix3X2& canvas_transformation,
596 const IGL2DTexturesStorageSP& textures_to_render) const throw() = 0;
603 const IGL2DTextureSP& texture) throw() = 0;
612 virtual
SDKResult SDK_CALLTYPE FinishDraw(const
bool& with_glfinish) throw() = 0;
613 inline
SDKResult SDK_CALLTYPE FinishDraw()
614 {
return FinishDraw(
true); }
619 virtual IGL2DDrawStatsSP SDK_CALLTYPE
GetDrawStats() const throw() = 0;
639 const
bool& is_enabled) throw() = 0;
648 const SDKMatrix3X2& matrix) throw() = 0;
655 SDKMatrix3X2& matrix) const throw() = 0;
659 const SDKMatrix3X2& matrix) throw() = 0;
662 const SDKMatrix3X2& matrix) throw() = 0;
665 SDKMatrix3X2& matrix) const throw() = 0;
672 SDKMatrix3X2& matrix) const throw() = 0;
680 const IGL2DClipRuleSP& rule) throw() = 0;
682 virtual IGL2DClipRuleSP SDK_CALLTYPE
GetClipRule() const throw() = 0;
688 virtual SDKAtomicRefCount SDK_CALLTYPE
AddRef()
const throw() = 0;
689 virtual SDKAtomicRefCount SDK_CALLTYPE Release() const throw() = 0;
690 virtual
SDKResult SDK_CALLTYPE GetInterface(
691 const
InterfaceId&
id,
void** obj_ptr) throw() = 0;
703 : m_canvas(canvas), m_locked(
false)
705 if (m_canvas && !m_canvas->IsCanvasLocked())
710 {
if (m_locked) m_canvas->UnLockCanvas(); }
712 inline bool IsLocked()
const
713 {
return m_canvas ? m_canvas->IsCanvasLocked() :
false; }
716 const IGL2DCanvasSP m_canvas;
725 : m_canvas(canvas), m_started(
false), m_with_glfinish(
true)
727 if (m_canvas && !m_canvas->IsDrawStarted())
731 const bool& with_glfinish)
732 : m_canvas(canvas), m_started(
false), m_with_glfinish(with_glfinish)
734 if (m_canvas && !m_canvas->IsDrawStarted())
739 {
if (m_started) m_canvas->FinishDraw(m_with_glfinish); }
741 inline bool IsStarted()
const
742 {
return m_canvas ? m_canvas->IsDrawStarted() :
false; }
745 const IGL2DCanvasSP m_canvas;
747 bool m_with_glfinish;
755 : m_canvas(canvas), m_applied(
false)
758 m_applied =
SDK_SUCCEEDED(m_canvas->PushObjectsTransformationMatrix(m));
762 {
if (m_applied) m_canvas->PopObjectsTransformationMatrix(); }
764 inline bool IsApplied()
const
765 {
return m_applied; }
768 const IGL2DCanvasSP m_canvas;
777 : m_canvas(canvas), m_applied(
false)
784 {
if (m_applied) m_canvas->ResetClipRule(); }
786 inline bool IsApplied()
const
787 {
return m_applied; }
790 const IGL2DCanvasSP m_canvas;
794 SDK_GL2D_END_NAMESPACE
796 #if defined (SDK_CC_GCC)
797 # pragma GCC diagnostic pop
800 #endif // SDK_GL2D_CANVAS_INTERFACE_H_
virtual bool SDK_CALLTYPE IsSameContextForDrawingAndResources() const =0
Returns true in case internal Resource GL context is same as internal GL Drawing context (Only one Op...
virtual bool SDK_CALLTYPE IsCanvasLocked() const =0
Checks, if canvas is locked.
A RGBA color.
Definition: color_base_types.h:15
virtual bool SDK_CALLTYPE IsDrawStarted() const =0
Checks, if draw in progress.
@ kGL2DCanvasPropertyID_CachedSymbolsCount
Definition: gl2d_canvas_interface.h:218
virtual SDKResult SDK_CALLTYPE RemoveObjectsTransformationMatrixes()=0
Removes all of applied objects transformation matrices.
@ kGL2DCreateCanvasSettingIDs_LogGlThreadUsage
Definition: gl2d_canvas_interface.h:410
virtual SDKResult SDK_CALLTYPE CreateTexturesStorage(IGL2DTexturesStorageSP &textures_storage) const =0
Creates new textures storage.
@ kGL2DCanvasPropertyID_DefFontBorderWidth
Definition: gl2d_canvas_interface.h:101
@ kGL2DCanvasPropertyID_DefLineRoundAngle
Definition: gl2d_canvas_interface.h:118
GL2DCanvasPropertyIDs
Generic GL2D Canvas properties.
Definition: gl2d_canvas_interface.h:76
virtual void SDK_CALLTYPE Dump() const =0
Dumps given object.
SDKResult SDK_CALLTYPE ResetClipRule()
Resets current clip rule.
Definition: gl2d_canvas_interface.h:684
virtual SDKResult SDK_CALLTYPE ToggleAntiAliasing(const bool &is_enabled)=0
Toggles anti-aliasing on/off.
@ kGL2DCanvasPropertyID_UseHighPriorityForGLThreads
Definition: gl2d_canvas_interface.h:210
virtual IGL2DStatsSP SDK_CALLTYPE GetStats() const =0
Returns OpenGL stats (OpenGL usage statistics)
virtual SDKResult SDK_CALLTYPE LockCanvas(const bool &release_internal_contexts)=0
Locks given GL2D canvas and suspends some or all of OpenGL operations Each lock operation should be f...
@ kGL2DCanvasPropertyID_MaxOzCoordinateValue
Definition: gl2d_canvas_interface.h:157
Provides with information about single registered font from GL2D fonts storage.
GL2D Draw Stats object, provides with statistics about last canvas draw operation (all of drawn objec...
@ kGL2DCreateCanvasSettingIDs_LogDirectory
Definition: gl2d_canvas_interface.h:383
Auto locks Canvas in ctor, unlocks in dtor.
Definition: gl2d_canvas_interface.h:699
virtual SDKResult SDK_CALLTYPE SetClipRule(const IGL2DClipRuleSP &rule)=0
Sets new clip rule.
virtual IGL2DDrawStatsSP SDK_CALLTYPE GetDrawStats() const =0
Returns last draw operation statistics.
@ kGL2DCanvasPropertyID_PolygonsAsLines
Definition: gl2d_canvas_interface.h:176
@ kGL2DCreateCanvasSettingIDs_ExtCreatedCtx
Definition: gl2d_canvas_interface.h:369
virtual GL2DPlatformType SDK_CALLTYPE GetPlatformType() const =0
Returns GL platform type (WGL/EGL/MESA/GLX/etc)
GL2DDeviceType
Device type (generic, iPhone, Samsung etc)
Definition: gl2d_canvas_interface.h:277
static const SDKColorF kGL2DWhiteClr
100% opaque white color
Definition: gl2d_canvas_interface.h:68
virtual IGL2DFontsStorageSP SDK_CALLTYPE GetFontsStorage() const =0
Returns Fonts Storage.
GL2DPlatformType
OpenGL platform type.
Definition: gl2d_canvas_interface.h:234
Platform-dependent GL objects.
@ kGL2DCanvasPropertyID_CachedCharMapsCount
Definition: gl2d_canvas_interface.h:222
GL2DCacheType
Cache type.
Definition: gl2d_canvas_interface.h:318
bool IsCanvasOperationSupported(const GL2DCanvasOperationType &type) const
Checks, if given operation supported by canvas Same as IGL2DCaps::IsCanvasOperationSupported.
Definition: gl2d_canvas_interface.h:479
#define SDK_SUCCEEDED(res)
Checks no error result.
Definition: sdk_results_enum.h:67
Object generic properties interface.
@ kGL2DCanvasPropertyID_AutoAcquireReleaseDrawLock
Definition: gl2d_canvas_interface.h:169
Auto starts draw in ctor, finishes in dtor.
Definition: gl2d_canvas_interface.h:721
@ kGL2DCanvasPropertyID_CurrentDrawCycleNum
Definition: gl2d_canvas_interface.h:161
GL2D factory, which allows to create appropriate GL2D object.
Definition: gl2d_factory_interface.h:35
@ kGL2DCanvasPropertyID_AdjustTextPosition
Definition: gl2d_canvas_interface.h:141
Uuid InterfaceId
Definition of interface UUID.
Definition: sdk_uuid.h:45
@ kGL2DCreateCanvasSettingIDs_LogGlCalls
Definition: gl2d_canvas_interface.h:396
Applies objects transformation matrix on ctor, removes on dtor.
Definition: gl2d_canvas_interface.h:751
@ kGL2DCanvasPropertyID_AdjustLatin1TextPosition
Definition: gl2d_canvas_interface.h:147
@ kGL2DCanvasPropertyID_DefLineSmoothAngle
Definition: gl2d_canvas_interface.h:110
virtual SDKResult SDK_CALLTYPE GetObjectsTransformationMatrix(SDKMatrix3X2 &matrix) const =0
Returns current resulting object transformation matrix.
virtual SDKResult SDK_CALLTYPE StartDraw(const IGL2DTextureSP &texture)=0
Initiates new drawing process on texture. Texture can't be used during draw in progress In case conte...
virtual SDKResult SDK_CALLTYPE SetCanvasTransformationMatrix(const SDKMatrix3X2 &matrix)=0
Sets new canvas transformation matrix, removes previous one.
static const SDKColorF kGL2DTransparentClr
100% transparent color
Definition: gl2d_canvas_interface.h:66
GL2D Caps object, provides information about OpenGL/ES2 capabilities.
virtual SDKResult SDK_CALLTYPE GetCanvasTransformationMatrix(SDKMatrix3X2 &matrix) const =0
Returns current canvas transformation matrix.
@ kGL2DCanvasPropertyID_CacheCleanupTimeout
Definition: gl2d_canvas_interface.h:214
@ kGL2DCreateCanvasSettingIDs_LogGlTasks
Definition: gl2d_canvas_interface.h:405
virtual IGL2DClipRuleSP SDK_CALLTYPE CreateClipRule(const GL2DClipRuleType &type) const =0
Creates new clip rule of appropriate type.
@ kGL2DCanvasPropertyID_RemoveClipRuleOnDrawFinished
Definition: gl2d_canvas_interface.h:122
virtual IGL2DTextureSP SDK_CALLTYPE CloneActiveFboBackBuffer() const =0
Copies currently active FBO back-buffer to appropriate texture Allows to make screenshots of active F...
virtual SDKResult SDK_CALLTYPE ClearUpCache(const SDKUInt32 &cache_id) const =0
Tries to remove unused entries from appropriate canvas cache(s) cache_id - Combination of GL2DCacheTy...
SDKInt32 SDKResult
Type of all error or return codes which SDK functions can end with.
Definition: sdk_results.h:17
GL2DClipRuleType
Available clip rule types.
Definition: gl2d_clip_rule_interface.h:40
virtual GL2DCanvasType SDK_CALLTYPE GetCanvasType() const =0
Returns GL canvas type (OpenGL/OpenGL ES2/etc)
@ kGL2DCanvasPropertyID_Use32BitsTexturesForTexts
Definition: gl2d_canvas_interface.h:183
virtual SDKResult SDK_CALLTYPE Clear(const SDKColorF &clr) const =0
Clears whole canvas by specified color.
@ kGL2DCreateCanvasSettingIDs_GetGlProcAddr
Definition: gl2d_canvas_interface.h:353
virtual SDKResult SDK_CALLTYPE UnLockCanvas()=0
Unlocks previously locked canvas.
GL2D Stats object, provides with statistics about OpenGL usage.
virtual SDKResult SDK_CALLTYPE GetResourceGlContext(GlCtx &resource_ctx) const =0
Returns internal Resource GL context data (Canvas should be locked with release_internal_contexts = t...
virtual IGL2DCanvasDrawLockSP SDK_CALLTYPE GetDrawLock() const =0
Returns Canvas Draw Lock instance.
@ kGL2DCreateCanvasSettingIDs_BreakOnGlError
Definition: gl2d_canvas_interface.h:392
GL2DCanvasType
OpenGL canvas type.
Definition: gl2d_canvas_interface.h:268
virtual IGL2DClipRuleSP SDK_CALLTYPE GetClipRule() const =0
Returns current clip rule.
virtual SDKResult SDK_CALLTYPE PopObjectsTransformationMatrix()=0
Removes latest objects transformation matrix from matrices stack.
@ kGL2DCreateCanvasSettingIDs_UseSameCtxForResourceAndDrawing
Definition: gl2d_canvas_interface.h:379
@ kGL2DCanvasPropertyID_CachedGLBuffersCount
Some private properties, mostly for unittests.
Definition: gl2d_canvas_interface.h:226
Single 3D point.
Definition: geometry_base_types.h:101
@ kGL2DCreateCanvasSettingIDs_GlThread
Definition: gl2d_canvas_interface.h:347
virtual SDKResult SDK_CALLTYPE DrawTexturesToTexture(const IGL2DTextureSP &output_texture, const SDKMatrix3X2 &canvas_transformation, const SDKColorF &output_tex_clear_color, const IGL2DTexturesStorageSP &textures_to_render) const =0
Draws several textures to output texture. No need to call for StartDraw/FinishDraw for given operatio...
GL2DCreateCanvasSettingIDs
Available settings for new canvas.
Definition: gl2d_canvas_interface.h:338
static const SDKVertex3D kGL2DUndefinedPosition
Undefined position.
Definition: gl2d_canvas_interface.h:71
@ kGL2DCanvasPropertyID_TextTexturesAtlasBlockSize
Definition: gl2d_canvas_interface.h:189
@ kGL2DCanvasPropertyID_TextTexturesAtlasTextureHeight
Definition: gl2d_canvas_interface.h:201
virtual SDKResult SDK_CALLTYPE RemoveTransformationMatrixes()=0
Removes all of canvas/objects transformation matrixes.
@ kGL2DCanvasPropertyID_DefAntiAliasingWidth
Definition: gl2d_canvas_interface.h:95
@ kGL2DCanvasPropertyID_AllowExpandSymbolTexture
Definition: gl2d_canvas_interface.h:206
virtual SDKResult SDK_CALLTYPE GetTotalTransformationMatrix(SDKMatrix3X2 &matrix) const =0
Returns total (objects + canvas) transformation matrix, applied to canvas.
GL2D Canvas to use to drawing NOTE! Create/Draw functionality was moved to appropriate GL2D Canvas Fu...
Definition: gl2d_canvas_interface.h:435
@ kGL2DCanvasPropertyID_TextsBlurring
Definition: gl2d_canvas_interface.h:153
virtual IGL2DFactorySP SDK_CALLTYPE GetParent() const =0
Returns parent factory object.
virtual SDKResult SDK_CALLTYPE ReduceCacheSize(const SDKUInt32 &cache_id, const SDKUInt64 &size_to_reduce) const =0
Tries to reduce appropriate cache size by removing unused items Only kGL2DGL2DCacheType_GLBuffers can...
Applies canvas clip rule on ctor, removes on dtor.
Definition: gl2d_canvas_interface.h:773
GL2D fonts storage, which allows to register/unregister/manage fonts collection. Only registered font...
Definition: gl2d_fonts_storage_interface.h:36
virtual SDKResult SDK_CALLTYPE ApplyCanvasTransformationMatrix(const SDKMatrix3X2 &matrix)=0
Applies new canvas transformation matrix to current canvas transformation.
virtual SDKResult SDK_CALLTYPE GetDrawingGlContext(GlCtx &drawing_ctx) const =0
Returns internal Drawing GL context data (Canvas should be locked with release_internal_contexts = tr...
@ kGL2DCanvasPropertyID_RootShadersFolder
Definition: gl2d_canvas_interface.h:84
@ kGL2DCreateCanvasSettingIDs_CheckGlCalls
Definition: gl2d_canvas_interface.h:387
@ kGL2DCanvasPropertyID_TextTexturesAtlasTextureWidth
Definition: gl2d_canvas_interface.h:195
GL2DCanvasOperationType
Available canvas operations.
Definition: gl2d_caps_interface.h:58
virtual SDKResult SDK_CALLTYPE PushObjectsTransformationMatrix(const SDKMatrix3X2 &matrix)=0
Adds new objects transformation matrix to transformation matrices stack.
virtual GL2DDeviceType SDK_CALLTYPE GetDeviceType() const =0
Returns device type (Generic/iPhone/whatever)
virtual SDKAtomicRefCount SDK_CALLTYPE AddRef() const =0
ISDKComponent own declaration.
static const float kGL2DCanvasDefTextBorderWidth
Default text border width for bordered texts.
Definition: gl2d_canvas_interface.h:429
virtual SDKResult SDK_CALLTYPE EnsureGLDataLoaded() const =0
Some devices have issues while working with separate Resource/Drawing contexts, in case GL object is ...
bool SDK_CALLTYPE IsSeparateContextsForDrawingAndResources() const
Returns true in case internal Resource GL context is not same as internal Drawing GL context.
Definition: gl2d_canvas_interface.h:553
virtual SDKSize SDK_CALLTYPE GetSize() const =0
Returns current canvas size Draw should be in progress, otherwise canvas size is zero Returns either ...
@ kGL2DCanvasPropertyID_DontCreateNonRenderableObjects
Definition: gl2d_canvas_interface.h:127
virtual SDKResult SDK_CALLTYPE ForceUnlockAndResume()=0
NL-1671: retained as a no-op vtable slot for ABI compatibility (was a Fix-4 recovery entry point; rec...
@ kGL2DCreateCanvasSettingIDs_LogGlCallPerf
Definition: gl2d_canvas_interface.h:400
SDK return values synonyms in the sdk namespace.
@ kGL2DCanvasPropertyID_AllowCreateCompatibleObject
Definition: gl2d_canvas_interface.h:134
static const float SDK_MAX_FLOAT
Max limit of float.
Definition: platform.h:197
SizeUI.
Definition: geometry_base_types.h:1235
FWD_DECL_INTERFACE(ILWEParserWrapper)
Provides a wrapper around the message parser to get, add or remove the.
virtual IGL2DCapsSP SDK_CALLTYPE GetCaps() const =0
Returns OpenGL caps (OpenGL capabilities info)
Platform-specific OpenGL/ES2 context.
Definition: gl2d_objects.h:170
virtual bool SDK_CALLTYPE IsAntiAliasingEnabled() const =0
Returns current state of anti-aliasing flag (enabled/disabled)