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39
40#ifndef QOPENGLPAINTENGINE_P_H
41#define QOPENGLPAINTENGINE_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists purely as an
48// implementation detail. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtGui/private/qtguiglobal_p.h>
55#include <QDebug>
56
57#include <qopenglpaintdevice.h>
58
59#include <private/qpaintengineex_p.h>
60#include <private/qopenglengineshadermanager_p.h>
61#include <private/qopengl2pexvertexarray_p.h>
62#include <private/qfontengine_p.h>
63#include <private/qdatabuffer_p.h>
64#include <private/qtriangulatingstroker_p.h>
65
66#include <private/qopenglextensions_p.h>
67
68#include <QOpenGLVertexArrayObject>
69#include <QOpenGLBuffer>
70
71enum EngineMode {
72 ImageDrawingMode,
73 TextDrawingMode,
74 BrushDrawingMode,
75 ImageArrayDrawingMode,
76 ImageOpacityArrayDrawingMode
77};
78
79QT_BEGIN_NAMESPACE
80
81#define GL_STENCIL_HIGH_BIT GLuint(0x80)
82#define QT_UNKNOWN_TEXTURE_UNIT GLuint(-1)
83#define QT_DEFAULT_TEXTURE_UNIT GLuint(0)
84#define QT_BRUSH_TEXTURE_UNIT GLuint(0)
85#define QT_IMAGE_TEXTURE_UNIT GLuint(0) //Can be the same as brush texture unit
86#define QT_MASK_TEXTURE_UNIT GLuint(1)
87#define QT_BACKGROUND_TEXTURE_UNIT GLuint(2)
88
89class QOpenGL2PaintEngineExPrivate;
90
91class QOpenGL2PaintEngineState : public QPainterState
92{
93public:
94 QOpenGL2PaintEngineState(QOpenGL2PaintEngineState &other);
95 QOpenGL2PaintEngineState();
96 ~QOpenGL2PaintEngineState();
97
98 uint isNew : 1;
99 uint needsClipBufferClear : 1;
100 uint clipTestEnabled : 1;
101 uint canRestoreClip : 1;
102 uint matrixChanged : 1;
103 uint compositionModeChanged : 1;
104 uint opacityChanged : 1;
105 uint renderHintsChanged : 1;
106 uint clipChanged : 1;
107 uint currentClip : 8;
108
109 QRect rectangleClip;
110};
111
112class Q_GUI_EXPORT QOpenGL2PaintEngineEx : public QPaintEngineEx
113{
114 Q_DECLARE_PRIVATE(QOpenGL2PaintEngineEx)
115public:
116 QOpenGL2PaintEngineEx();
117 ~QOpenGL2PaintEngineEx();
118
119 bool begin(QPaintDevice *device) override;
120 void ensureActive();
121 bool end() override;
122
123 virtual void clipEnabledChanged() override;
124 virtual void penChanged() override;
125 virtual void brushChanged() override;
126 virtual void brushOriginChanged() override;
127 virtual void opacityChanged() override;
128 virtual void compositionModeChanged() override;
129 virtual void renderHintsChanged() override;
130 virtual void transformChanged() override;
131
132 virtual void drawPixmap(const QRectF &r, const QPixmap &pm, const QRectF &sr) override;
133 virtual void drawPixmapFragments(const QPainter::PixmapFragment *fragments, int fragmentCount, const QPixmap &pixmap,
134 QPainter::PixmapFragmentHints hints) override;
135 virtual void drawImage(const QRectF &r, const QImage &pm, const QRectF &sr,
136 Qt::ImageConversionFlags flags = Qt::AutoColor) override;
137 virtual void drawTextItem(const QPointF &p, const QTextItem &textItem) override;
138 virtual void fill(const QVectorPath &path, const QBrush &brush) override;
139 virtual void stroke(const QVectorPath &path, const QPen &pen) override;
140 virtual void clip(const QVectorPath &path, Qt::ClipOperation op) override;
141
142 virtual void drawStaticTextItem(QStaticTextItem *textItem) override;
143
144 bool drawTexture(const QRectF &r, GLuint textureId, const QSize &size, const QRectF &sr);
145
146 Type type() const override { return OpenGL2; }
147
148 virtual void setState(QPainterState *s) override;
149 virtual QPainterState *createState(QPainterState *orig) const override;
150 inline QOpenGL2PaintEngineState *state() {
151 return static_cast<QOpenGL2PaintEngineState *>(QPaintEngineEx::state());
152 }
153 inline const QOpenGL2PaintEngineState *state() const {
154 return static_cast<const QOpenGL2PaintEngineState *>(QPaintEngineEx::state());
155 }
156
157 void beginNativePainting() override;
158 void endNativePainting() override;
159
160 void invalidateState();
161
162 void setRenderTextActive(bool);
163
164 bool isNativePaintingActive() const;
165 bool requiresPretransformedGlyphPositions(QFontEngine *, const QTransform &) const override { return false; }
166 bool shouldDrawCachedGlyphs(QFontEngine *, const QTransform &) const override;
167
168private:
169 Q_DISABLE_COPY_MOVE(QOpenGL2PaintEngineEx)
170
171 friend class QOpenGLEngineShaderManager;
172};
173
174// This probably needs to grow to GL_MAX_VERTEX_ATTRIBS, but 3 is ok for now as that's
175// all the GL2 engine uses:
176#define QT_GL_VERTEX_ARRAY_TRACKED_COUNT 3
177
178class QOpenGL2PaintEngineExPrivate : public QPaintEngineExPrivate
179{
180 Q_DECLARE_PUBLIC(QOpenGL2PaintEngineEx)
181public:
182 enum StencilFillMode {
183 OddEvenFillMode,
184 WindingFillMode,
185 TriStripStrokeFillMode
186 };
187
188 QOpenGL2PaintEngineExPrivate(QOpenGL2PaintEngineEx *q_ptr) :
189 q(q_ptr),
190 shaderManager(nullptr),
191 width(0), height(0),
192 ctx(nullptr),
193 useSystemClip(true),
194 elementIndicesVBOId(0),
195 opacityArray(0),
196 snapToPixelGrid(false),
197 nativePaintingActive(false),
198 inverseScale(1),
199 lastTextureUnitUsed(QT_UNKNOWN_TEXTURE_UNIT),
200 vertexBuffer(QOpenGLBuffer::VertexBuffer),
201 texCoordBuffer(QOpenGLBuffer::VertexBuffer),
202 opacityBuffer(QOpenGLBuffer::VertexBuffer),
203 indexBuffer(QOpenGLBuffer::IndexBuffer)
204 { }
205
206 ~QOpenGL2PaintEngineExPrivate();
207
208 void updateBrushTexture();
209 void updateBrushUniforms();
210 void updateMatrix();
211 void updateCompositionMode();
212
213 enum TextureUpdateMode { UpdateIfNeeded, ForceUpdate };
214 template<typename T>
215 void updateTexture(GLenum textureUnit, const T &texture, GLenum wrapMode, GLenum filterMode, TextureUpdateMode updateMode = UpdateIfNeeded);
216 template<typename T>
217 GLuint bindTexture(const T &texture);
218 void activateTextureUnit(GLenum textureUnit);
219
220 void resetGLState();
221
222 // fill, stroke, drawTexture, drawPixmaps & drawCachedGlyphs are the main rendering entry-points,
223 // however writeClip can also be thought of as en entry point as it does similar things.
224 void fill(const QVectorPath &path);
225 void stroke(const QVectorPath &path, const QPen &pen);
226 void drawTexture(const QOpenGLRect& dest, const QOpenGLRect& src, const QSize &textureSize, bool opaque, bool pattern = false);
227 void drawPixmapFragments(const QPainter::PixmapFragment *fragments, int fragmentCount, const QPixmap &pixmap,
228 QPainter::PixmapFragmentHints hints);
229 void drawCachedGlyphs(QFontEngine::GlyphFormat glyphFormat, QStaticTextItem *staticTextItem);
230
231 // Calls glVertexAttributePointer if the pointer has changed
232 inline void uploadData(unsigned int arrayIndex, const GLfloat *data, GLuint count);
233 inline bool uploadIndexData(const void *data, GLenum indexValueType, GLuint count);
234
235 // draws whatever is in the vertex array:
236 void drawVertexArrays(const float *data, int *stops, int stopCount, GLenum primitive);
237 void drawVertexArrays(QOpenGL2PEXVertexArray &vertexArray, GLenum primitive) {
238 drawVertexArrays(data: (const float *) vertexArray.data(), stops: vertexArray.stops(), stopCount: vertexArray.stopCount(), primitive);
239 }
240
241 // Composites the bounding rect onto dest buffer:
242 void composite(const QOpenGLRect& boundingRect);
243
244 // Calls drawVertexArrays to render into stencil buffer:
245 void fillStencilWithVertexArray(const float *data, int count, int *stops, int stopCount, const QOpenGLRect &bounds, StencilFillMode mode);
246 void fillStencilWithVertexArray(QOpenGL2PEXVertexArray& vertexArray, bool useWindingFill) {
247 fillStencilWithVertexArray(data: (const float *) vertexArray.data(), count: 0, stops: vertexArray.stops(), stopCount: vertexArray.stopCount(),
248 bounds: vertexArray.boundingRect(),
249 mode: useWindingFill ? WindingFillMode : OddEvenFillMode);
250 }
251
252 void setBrush(const QBrush& brush);
253 void transferMode(EngineMode newMode);
254 bool prepareForDraw(bool srcPixelsAreOpaque); // returns true if the program has changed
255 bool prepareForCachedGlyphDraw(const QFontEngineGlyphCache &cache);
256 inline void useSimpleShader();
257 inline GLuint location(const QOpenGLEngineShaderManager::Uniform uniform) {
258 return shaderManager->getUniformLocation(id: uniform);
259 }
260
261 void clearClip(uint value);
262 void writeClip(const QVectorPath &path, uint value);
263 void resetClipIfNeeded();
264
265 void updateClipScissorTest();
266 void setScissor(const QRect &rect);
267 void regenerateClip();
268 void systemStateChanged() override;
269
270 void setVertexAttribArrayEnabled(int arrayIndex, bool enabled = true);
271 void syncGlState();
272
273 static QOpenGLEngineShaderManager* shaderManagerForEngine(QOpenGL2PaintEngineEx *engine) { return engine->d_func()->shaderManager; }
274 static QOpenGL2PaintEngineExPrivate *getData(QOpenGL2PaintEngineEx *engine) { return engine->d_func(); }
275 static void cleanupVectorPath(QPaintEngineEx *engine, void *data);
276
277 QOpenGLExtensions funcs;
278
279 QOpenGL2PaintEngineEx* q;
280 QOpenGLEngineShaderManager* shaderManager;
281 QOpenGLPaintDevice* device;
282 int width, height;
283 QOpenGLContext *ctx;
284 EngineMode mode;
285 QFontEngine::GlyphFormat glyphCacheFormat;
286
287 bool vertexAttributeArraysEnabledState[QT_GL_VERTEX_ARRAY_TRACKED_COUNT];
288
289 // Dirty flags
290 bool matrixDirty; // Implies matrix uniforms are also dirty
291 bool compositionModeDirty;
292 bool brushTextureDirty;
293 bool brushUniformsDirty;
294 bool opacityUniformDirty;
295 bool matrixUniformDirty;
296
297 bool stencilClean; // Has the stencil not been used for clipping so far?
298 bool useSystemClip;
299 QRegion dirtyStencilRegion;
300 QRect currentScissorBounds;
301 uint maxClip;
302
303 QBrush currentBrush; // May not be the state's brush!
304 const QBrush noBrush;
305
306 QImage currentBrushImage;
307
308 QOpenGL2PEXVertexArray vertexCoordinateArray;
309 QOpenGL2PEXVertexArray textureCoordinateArray;
310 QVector<GLushort> elementIndices;
311 GLuint elementIndicesVBOId;
312 QDataBuffer<GLfloat> opacityArray;
313 GLfloat staticVertexCoordinateArray[8];
314 GLfloat staticTextureCoordinateArray[8];
315
316 bool snapToPixelGrid;
317 bool nativePaintingActive;
318 GLfloat pmvMatrix[3][3];
319 GLfloat inverseScale;
320
321 GLenum lastTextureUnitUsed;
322 GLuint lastTextureUsed;
323
324 QOpenGLVertexArrayObject vao;
325 QOpenGLBuffer vertexBuffer;
326 QOpenGLBuffer texCoordBuffer;
327 QOpenGLBuffer opacityBuffer;
328 QOpenGLBuffer indexBuffer;
329
330 bool needsSync;
331 bool multisamplingAlwaysEnabled;
332
333 QTriangulatingStroker stroker;
334 QDashedStrokeProcessor dasher;
335
336 QVector<GLuint> unusedVBOSToClean;
337 QVector<GLuint> unusedIBOSToClean;
338
339 const GLfloat *vertexAttribPointers[3];
340};
341
342
343void QOpenGL2PaintEngineExPrivate::uploadData(unsigned int arrayIndex, const GLfloat *data, GLuint count)
344{
345 Q_ASSERT(arrayIndex < 3);
346
347 // If a vertex array object is created we have a profile that supports them
348 // and we will upload the data via a QOpenGLBuffer. Otherwise we will use
349 // the legacy way of uploading the data via glVertexAttribPointer.
350 if (vao.isCreated()) {
351 if (arrayIndex == QT_VERTEX_COORDS_ATTR) {
352 vertexBuffer.bind();
353 vertexBuffer.allocate(data, count: count * sizeof(float));
354 }
355 if (arrayIndex == QT_TEXTURE_COORDS_ATTR) {
356 texCoordBuffer.bind();
357 texCoordBuffer.allocate(data, count: count * sizeof(float));
358 }
359 if (arrayIndex == QT_OPACITY_ATTR) {
360 opacityBuffer.bind();
361 opacityBuffer.allocate(data, count: count * sizeof(float));
362 }
363 if (arrayIndex == QT_OPACITY_ATTR)
364 funcs.glVertexAttribPointer(indx: arrayIndex, size: 1, GL_FLOAT, GL_FALSE, stride: 0, ptr: nullptr);
365 else
366 funcs.glVertexAttribPointer(indx: arrayIndex, size: 2, GL_FLOAT, GL_FALSE, stride: 0, ptr: nullptr);
367 } else {
368 // If we already uploaded the data we don't have to do it again
369 if (data == vertexAttribPointers[arrayIndex])
370 return;
371
372 // Store the data in cache and upload it to the graphics card.
373 vertexAttribPointers[arrayIndex] = data;
374 if (arrayIndex == QT_OPACITY_ATTR)
375 funcs.glVertexAttribPointer(indx: arrayIndex, size: 1, GL_FLOAT, GL_FALSE, stride: 0, ptr: data);
376 else
377 funcs.glVertexAttribPointer(indx: arrayIndex, size: 2, GL_FLOAT, GL_FALSE, stride: 0, ptr: data);
378 }
379}
380
381bool QOpenGL2PaintEngineExPrivate::uploadIndexData(const void *data, GLenum indexValueType, GLuint count)
382{
383 // Follow the uploadData() logic: VBOs are used only when VAO support is available.
384 // Otherwise the legacy client-side pointer path is used.
385 if (vao.isCreated()) {
386 Q_ASSERT(indexValueType == GL_UNSIGNED_SHORT || indexValueType == GL_UNSIGNED_INT);
387 indexBuffer.bind();
388 indexBuffer.allocate(data, count: count * (indexValueType == GL_UNSIGNED_SHORT ? sizeof(quint16) : sizeof(quint32)));
389 return true;
390 }
391 return false;
392}
393
394QT_END_NAMESPACE
395
396#endif
397

source code of qtbase/src/gui/opengl/qopenglpaintengine_p.h