drawing ellipses antialiased with Cairo

libcore/imagecache.c

@@ -3,9 +3,10 @@
 #include <map>
 #include <fstream>
 #include <sys/stat.h>
-#include "imagecache.h"
+#include "imagecreator.h"
 #include "../config.h"
 #include "helpers.h"
+#include "imagecache.h"
 
 
 cMutex cImageCache::mutex;
@@ -300,6 +301,37 @@ cImage *cImageCache::GetSkinpart(string name, int width, int height) {
     return NULL;    
 }
 
+void cImageCache::CacheEllipse(int id, int width, int height, tColor color, int quadrant) {
+    esyslog("skindesigner: caching ellipse %d, w %d, h %d, color %x, quadrant %d", id, width, height, color, quadrant);
+    GetEllipse(id, width, height, color, quadrant);
+}
+
+cImage *cImageCache::GetEllipse(int id, int width, int height, tColor color, int quadrant) {
+    if (width < 1 || width > 1920 || height < 1 || height > 1080)
+        return NULL;
+    cMutexLock MutexLock(&mutex);
+    map<int, cImage*>::iterator hit = cairoImageCache.find(id);
+    if (hit != cairoImageCache.end()) {
+        return (cImage*)hit->second;
+    } else {
+        cImageCreator ic;
+        if (!ic.InitCairoImage(width, height))
+            return NULL;
+        ic.DrawEllipse(color, quadrant);
+        cImage *ellipse = ic.GetImage();
+        cairoImageCache.insert(pair<int, cImage*>(id, ellipse));
+        hit = cairoImageCache.find(id);
+        if (hit != cairoImageCache.end()) {
+            return (cImage*)hit->second;
+        }
+    }
+    return NULL;
+}
+
+/****************************************************************************************
+* PRIVATE FUNCTIONS
+****************************************************************************************/
+
 bool cImageCache::LoadIcon(eImageType type, string name) {
     cString subdir("");
     if (type == itMenuIcon)
@@ -361,11 +393,17 @@ void cImageCache::Clear(void) {
     }
     channelLogoCache.clear();
 
-    for(map<std::string, cImage*>::const_iterator it = skinPartsCache.begin(); it != skinPartsCache.end(); it++) {
+    for(map<string, cImage*>::const_iterator it = skinPartsCache.begin(); it != skinPartsCache.end(); it++) {
         cImage *img = (cImage*)it->second;
         delete img;
     }
     skinPartsCache.clear();
+
+    for(map<int, cImage*>::const_iterator it = cairoImageCache.begin(); it != cairoImageCache.end(); it++) {
+        cImage *img = (cImage*)it->second;
+        delete img;
+    }
+    cairoImageCache.clear();
 }
 
 void cImageCache::Debug(bool full) {

libcore/imagecache.h

@@ -30,6 +30,9 @@ public:
     //skinparts
     void CacheSkinpart(string path, int width, int height);
     cImage *GetSkinpart(string name, int width, int height);
+    //Cairo Images
+    void CacheEllipse(int id, int width, int height, tColor color, int quadrant);
+    cImage *GetEllipse(int id, int width, int height, tColor color, int quadrant);
     //helpers
     void Clear(void);
     void Debug(bool full);
@@ -46,6 +49,7 @@ private:
     map<string, cImage*> iconCache;
     map<string, cImage*> channelLogoCache;
     map<string, cImage*> skinPartsCache;
+    map<int, cImage*> cairoImageCache;
     bool LoadIcon(eImageType type, string name);
     bool LoadLogo(const cChannel *channel);
     bool LoadSeparatorLogo(string name);

libcore/imagecreator.c

@@ -0,0 +1,202 @@
+#include "imagecreator.h"
+
+cImageCreator::cImageCreator(void) {
+	surface = NULL;
+	cr = NULL;
+}
+
+cImageCreator::~cImageCreator() {
+    if (cr)
+	    cairo_destroy (cr);
+    if (surface)
+	    cairo_surface_destroy (surface);
+}
+
+bool cImageCreator::InitCairoImage(int width, int height) {
+	this->width = width;
+	this->height = height;
+	if (width < 1 || height < 1 || width > 1920 || height > 1080)
+		return false;
+	surface = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height);
+    cr = cairo_create(surface);
+    cairo_set_antialias(cr, CAIRO_ANTIALIAS_BEST);
+    return true;
+}
+
+/**********************************************************************************
+* Public Functions
+**********************************************************************************/
+
+///< 0       draws the entire ellipse
+///< 1..4    draws only the first, second, third or fourth quadrant, respectively
+///< 5..8    draws the right, top, left or bottom half, respectively
+///< -1..-4  draws the inverted part of the given quadrant
+///< If Quadrants is not 0, the coordinates are those of the actual area, not
+///< the full circle!
+void cImageCreator::DrawEllipse(tColor color, int quadrants) {
+    if (!cr || !surface)
+        return;
+	//center of the ellipse
+	double x, y;
+	//radius 
+	double radius;
+	//start and stop angle (radian)
+	double arcStart, arcStop;
+	//scaling factors
+	double scaleX, scaleY;
+	//draw inverted ellipse
+	bool inverted;
+
+	scaleX = width;
+	scaleY = height;
+	inverted = false;
+
+	switch (quadrants) {
+		case 0:
+			x = 0.5;
+			y = 0.5;
+			radius = 0.5;
+			arcStart = 0.0;
+			arcStop = 2 * M_PI;
+			break;
+		case 1:
+			x = 0.0;
+			y = 1.0;
+			radius = 1.0;
+			arcStart = M_PI;
+			arcStop = 2 * M_PI;
+			break;
+		case 2:
+			x = 1.0;
+			y = 1.0;
+			radius = 1.0;
+			arcStart = M_PI;
+			arcStop = 2 * M_PI;
+			break;
+		case 3:
+			x = 1.0;
+			y = 0.0;
+			radius = 1.0;
+			arcStart = 0;
+			arcStop = M_PI;
+			break;
+		case 4:
+			x = 0.0;
+			y = 0.0;
+			radius = 1.0;
+			arcStart = 0;
+			arcStop = M_PI;
+			break;
+		case 5:
+		    scaleX = 2 * width;
+		    x = 0.0;
+		    y = 0.5;
+		    radius = 0.5;
+		    arcStart = 0;
+		    arcStop = 2* M_PI;
+			break;
+		case 6:
+		    scaleY = 2 * height;
+		    x = 0.5;
+		    y = 0.5;
+		    radius = 0.5;
+		    arcStart = 0;
+		    arcStop = 2* M_PI;
+			break;
+		case 7:
+		    scaleX = 2 * width;
+		    x = 0.5;
+		    y = 0.5;
+		    radius = 0.5;
+		    arcStart = 0;
+		    arcStop = 2* M_PI;
+			break;
+		case 8:
+		    scaleY = 2 * height;
+		    x = 0.5;
+		    y = 0.0;
+		    radius = 0.5;
+		    arcStart = 0;
+		    arcStop = 2* M_PI;
+			break;
+		case -1:
+		    x = 0.0;
+		    y = 1.0;
+		    radius = 1.0;
+		    arcStart = M_PI;
+		    arcStop = 2* M_PI;
+		    inverted = true;
+		    break;
+		case -2:
+			x = 1.0;
+			y = 1.0;
+			radius = 1.0;
+			arcStart = M_PI;
+			arcStop = 2 * M_PI;
+		    inverted = true;
+		    break;
+		case -3:
+			x = 1.0;
+			y = 0.0;
+			radius = 1.0;
+			arcStart = 0;
+			arcStop = M_PI;
+		    inverted = true;
+			break;
+		case -4:
+			x = 0.0;
+			y = 0.0;
+			radius = 1.0;
+			arcStart = 0;
+			arcStop = M_PI;
+		    inverted = true;
+			break;
+		default:
+			x = 0.5;
+			y = 0.5;
+			radius = 0.5;
+			arcStart = 0.0;
+			arcStop = 2 * M_PI;
+			break;
+	}
+
+	SetColor(color);
+	//Draw Background for inverted ellipses
+	if (inverted) {
+	    cairo_rectangle(cr, 0.0, 0.0, width, height);
+	    cairo_fill (cr);
+	    cairo_set_operator(cr, CAIRO_OPERATOR_CLEAR);
+	}
+	//Draw Ellipse
+	cairo_scale(cr, scaleX, scaleY);
+	cairo_arc(cr, x, y, radius, arcStart, arcStop);
+	cairo_fill(cr);
+}
+
+cImage *cImageCreator::GetImage(void) {
+    if (!cr || !surface)
+        NULL;
+	unsigned char *data = cairo_image_surface_get_data(surface);
+    cImage *image = new cImage(cSize(width, height), (tColor*)data);
+    return image;
+}
+
+/**********************************************************************************
+* Private Functions
+**********************************************************************************/
+
+void cImageCreator::SetColor(tColor color) {
+    if (!cr || !surface)
+        return;
+	tIndex tAlpha = (color & 0xFF000000) >> 24;
+    tIndex tRed = (color & 0x00FF0000) >> 16;
+    tIndex tGreen = (color & 0x0000FF00) >> 8;
+    tIndex tBlue = (color & 0x000000FF);
+    
+    double a = (int)tAlpha / (double)255;
+    double r = (int)tRed / (double)255;
+    double g = (int)tGreen / (double)255;
+    double b = (int)tBlue / (double)255;
+
+    cairo_set_source_rgba(cr, r, g, b, a);
+}

libcore/imagecreator.h

@@ -0,0 +1,26 @@
+#ifndef __IMAGECREATOR_H
+#define __IMAGECREATOR_H
+
+#include <cairo.h>
+#include <vdr/osd.h>
+#include <string>
+#include <sstream>
+
+using namespace std;
+
+class cImageCreator {
+private:
+    int width;
+    int height;
+    cairo_surface_t *surface;
+    cairo_t *cr;
+    void SetColor(tColor color);
+public:
+    cImageCreator(void);
+    virtual ~cImageCreator();
+    bool InitCairoImage(int width, int height);
+    void DrawEllipse(tColor color, int quadrants = 0);
+    cImage *GetImage(void);
+};
+
+#endif //__IMAGECREATOR_H