sw_engine composition: invert alpha masking

composition invert alpha masking

@Examples: added InvMasking

@Issues: 31

Change-Id: I2ee9d428d5749240ddf2e6adbb7677dccbe1926f

inc/thorvg.h

@@ -51,7 +51,7 @@ enum class TVG_EXPORT StrokeCap { Square = 0, Round, Butt };
 enum class TVG_EXPORT StrokeJoin { Bevel = 0, Round, Miter };
 enum class TVG_EXPORT FillSpread { Pad = 0, Reflect, Repeat };
 enum class TVG_EXPORT FillRule { Winding = 0, EvenOdd };
-enum class TVG_EXPORT CompositeMethod { None = 0, ClipPath, AlphaMask };
+enum class TVG_EXPORT CompositeMethod { None = 0, ClipPath, AlphaMask, InvAlphaMask };
 enum class TVG_EXPORT CanvasEngine { Sw = (1 << 1), Gl = (1 << 2)};
 
 
@@ -390,4 +390,4 @@ public:
 }
 #endif
 
-#endif //_THORVG_H_
+#endif //_THORVG_H_

src/examples/InvMasking.cpp

@@ -0,0 +1,200 @@
+#include "Common.h"
+#include <fstream>
+
+/************************************************************************/
+/* Drawing Commands                                                     */
+/************************************************************************/
+
+uint32_t *data = nullptr;
+
+void tvgDrawCmds(tvg::Canvas* canvas)
+{
+    if (!canvas) return;
+
+    //Solid Rectangle
+    auto shape = tvg::Shape::gen();
+    shape->appendRect(0, 0, 400, 400, 0, 0);
+    shape->fill(0, 0, 255, 255);
+
+    //Mask
+    auto mask = tvg::Shape::gen();
+    mask->appendCircle(200, 200, 125, 125);
+    mask->fill(255, 0, 0, 255);
+    shape->composite(move(mask), tvg::CompositeMethod::InvAlphaMask);
+    canvas->push(move(shape));
+
+    //SVG
+    auto svg = tvg::Picture::gen();
+    if (svg->load(EXAMPLE_DIR"/cartman.svg") != tvg::Result::Success) return;
+    svg->opacity(100);
+    svg->scale(3);
+    svg->translate(50, 400);
+
+    //Mask2
+    auto mask2 = tvg::Shape::gen();
+    mask2->appendCircle(150, 500, 75, 75);
+    mask2->appendRect(150, 500, 200, 200, 30, 30);
+    mask2->fill(255, 255, 255, 255);
+    svg->composite(move(mask2), tvg::CompositeMethod::InvAlphaMask);
+    if (canvas->push(move(svg)) != tvg::Result::Success) return;
+
+    //Star
+    auto star = tvg::Shape::gen();
+    star->fill(80, 80, 80, 255);
+    star->moveTo(599, 34);
+    star->lineTo(653, 143);
+    star->lineTo(774, 160);
+    star->lineTo(687, 244);
+    star->lineTo(707, 365);
+    star->lineTo(599, 309);
+    star->lineTo(497, 365);
+    star->lineTo(512, 245);
+    star->lineTo(426, 161);
+    star->lineTo(546, 143);
+    star->close();
+    star->stroke(10);
+    star->stroke(255, 255, 255, 255);
+
+    //Mask3
+    auto mask3 = tvg::Shape::gen();
+    mask3->appendCircle(600, 200, 125, 125);
+    mask3->fill(255, 255, 255, 255);
+    star->composite(move(mask3), tvg::CompositeMethod::InvAlphaMask);
+    if (canvas->push(move(star)) != tvg::Result::Success) return;
+
+    //Image
+    ifstream file(EXAMPLE_DIR"/rawimage_200x300.raw");
+    if (!file.is_open()) return;
+    data = (uint32_t*) malloc(sizeof(uint32_t) * (200 * 300));
+    file.read(reinterpret_cast<char *>(data), sizeof (data) * 200 * 300);
+    file.close();
+
+    auto image = tvg::Picture::gen();
+    if (image->load(data, 200, 300, true) != tvg::Result::Success) return;
+    image->translate(500, 400);
+
+    //Mask4
+    auto mask4 = tvg::Shape::gen();
+    mask4->moveTo(599, 384);
+    mask4->lineTo(653, 493);
+    mask4->lineTo(774, 510);
+    mask4->lineTo(687, 594);
+    mask4->lineTo(707, 715);
+    mask4->lineTo(599, 659);
+    mask4->lineTo(497, 715);
+    mask4->lineTo(512, 595);
+    mask4->lineTo(426, 511);
+    mask4->lineTo(546, 493);
+    mask4->close();
+    mask4->fill(255, 255, 255, 70);
+    image->composite(move(mask4), tvg::CompositeMethod::InvAlphaMask);
+    if (canvas->push(move(image)) != tvg::Result::Success) return;
+}
+
+
+/************************************************************************/
+/* Sw Engine Test Code                                                  */
+/************************************************************************/
+
+static unique_ptr<tvg::SwCanvas> swCanvas;
+
+void tvgSwTest(uint32_t* buffer)
+{
+    //Create a Canvas
+    swCanvas = tvg::SwCanvas::gen();
+    swCanvas->target(buffer, WIDTH, WIDTH, HEIGHT, tvg::SwCanvas::ARGB8888);
+
+    /* Push the shape into the Canvas drawing list
+       When this shape is into the canvas list, the shape could update & prepare
+       internal data asynchronously for coming rendering.
+       Canvas keeps this shape node unless user call canvas->clear() */
+    tvgDrawCmds(swCanvas.get());
+}
+
+void drawSwView(void* data, Eo* obj)
+{
+    if (swCanvas->draw() == tvg::Result::Success) {
+        swCanvas->sync();
+    }
+}
+
+
+/************************************************************************/
+/* GL Engine Test Code                                                  */
+/************************************************************************/
+
+static unique_ptr<tvg::GlCanvas> glCanvas;
+
+void initGLview(Evas_Object *obj)
+{
+    static constexpr auto BPP = 4;
+
+    //Create a Canvas
+    glCanvas = tvg::GlCanvas::gen();
+    glCanvas->target(nullptr, WIDTH * BPP, WIDTH, HEIGHT);
+
+    /* Push the shape into the Canvas drawing list
+       When this shape is into the canvas list, the shape could update & prepare
+       internal data asynchronously for coming rendering.
+       Canvas keeps this shape node unless user call canvas->clear() */
+    tvgDrawCmds(glCanvas.get());
+}
+
+void drawGLview(Evas_Object *obj)
+{
+    auto gl = elm_glview_gl_api_get(obj);
+    gl->glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
+    gl->glClear(GL_COLOR_BUFFER_BIT);
+
+    if (glCanvas->draw() == tvg::Result::Success) {
+        glCanvas->sync();
+    }
+}
+
+
+/************************************************************************/
+/* Main Code                                                            */
+/************************************************************************/
+
+int main(int argc, char **argv)
+{
+    tvg::CanvasEngine tvgEngine = tvg::CanvasEngine::Sw;
+
+    if (argc > 1) {
+        if (!strcmp(argv[1], "gl")) tvgEngine = tvg::CanvasEngine::Gl;
+    }
+
+    //Initialize ThorVG Engine
+    if (tvgEngine == tvg::CanvasEngine::Sw) {
+        cout << "tvg engine: software" << endl;
+    } else {
+        cout << "tvg engine: opengl" << endl;
+    }
+
+    //Threads Count
+    auto threads = std::thread::hardware_concurrency();
+
+    //Initialize ThorVG Engine
+    if (tvg::Initializer::init(tvgEngine, threads) == tvg::Result::Success) {
+
+        elm_init(argc, argv);
+
+        if (tvgEngine == tvg::CanvasEngine::Sw) {
+            createSwView();
+        } else {
+            createGlView();
+        }
+
+        elm_run();
+        elm_shutdown();
+
+        //Terminate ThorVG Engine
+        tvg::Initializer::term(tvg::CanvasEngine::Sw);
+
+        if (data) free(data);
+
+    } else {
+        cout << "engine is not supported" << endl;
+    }
+    return 0;
+}

src/examples/meson.build

@@ -32,6 +32,7 @@ source_file = [
     'Update.cpp',
     'ClipPath.cpp',
     'Masking.cpp',
+    'InvMasking.cpp',
 ]
 
 foreach current_file : source_file

src/lib/sw_engine/tvgSwRaster.cpp

@@ -147,6 +147,30 @@ static bool _translucentRectAlphaMask(SwSurface* surface, const SwBBox& region,
     return true;
 }
 
+static bool _translucentRectInvAlphaMask(SwSurface* surface, const SwBBox& region, uint32_t color)
+{
+    auto buffer = surface->buffer + (region.min.y * surface->stride) + region.min.x;
+    auto h = static_cast<uint32_t>(region.max.y - region.min.y);
+    auto w = static_cast<uint32_t>(region.max.x - region.min.x);
+
+#ifdef THORVG_LOG_ENABLED
+    printf("SW_ENGINE: Rectangle Alpha Mask Composition\n");
+#endif
+
+    auto cbuffer = surface->compositor->image.data + (region.min.y * surface->stride) + region.min.x;   //compositor buffer
+
+    for (uint32_t y = 0; y < h; ++y) {
+        auto dst = &buffer[y * surface->stride];
+        auto cmp = &cbuffer[y * surface->stride];
+        for (uint32_t x = 0; x < w; ++x) {
+            auto ialpha = 255 - surface->blender.alpha(*cmp);
+            auto tmp = ALPHA_BLEND(color, ialpha);
+            dst[x] = tmp + ALPHA_BLEND(dst[x], 255 - surface->blender.alpha(tmp));
+            ++cmp;
+        }
+    }
+    return true;
+}
 
 static bool _rasterTranslucentRect(SwSurface* surface, const SwBBox& region, uint32_t color)
 {
@@ -154,6 +178,9 @@ static bool _rasterTranslucentRect(SwSurface* surface, const SwBBox& region, uin
         if (surface->compositor->method == CompositeMethod::AlphaMask) {
             return _translucentRectAlphaMask(surface, region, color);
         }
+        if (surface->compositor->method == CompositeMethod::InvAlphaMask) {
+            return _translucentRectInvAlphaMask(surface, region, color);
+        }
     }
     return _translucentRect(surface, region, color);
 }
@@ -223,6 +250,33 @@ static bool _translucentRleAlphaMask(SwSurface* surface, SwRleData* rle, uint32_
     return true;
 }
 
+static bool _translucentRleInvAlphaMask(SwSurface* surface, SwRleData* rle, uint32_t color)
+{
+#ifdef THORVG_LOG_ENABLED
+    printf("SW_ENGINE: Rle Alpha Mask Composition\n");
+#endif
+    auto span = rle->spans;
+    uint32_t src;
+    auto tbuffer = static_cast<uint32_t*>(alloca(sizeof(uint32_t) * surface->w));  //temp buffer for intermediate processing
+    auto cbuffer = surface->compositor->image.data;
+
+    for (uint32_t i = 0; i < rle->size; ++i) {
+        auto dst = &surface->buffer[span->y * surface->stride + span->x];
+        auto cmp = &cbuffer[span->y * surface->stride + span->x];
+        auto tmp = tbuffer;
+        if (span->coverage < 255) src = ALPHA_BLEND(color, span->coverage);
+        else src = color;
+        for (uint32_t x = 0; x < span->len; ++x) {
+            auto ialpha = 255 - surface->blender.alpha(*cmp);
+            *tmp = ALPHA_BLEND(src, ialpha);
+            dst[x] = *tmp + ALPHA_BLEND(dst[x], 255 - surface->blender.alpha(*tmp));
+            ++tmp;
+            ++cmp;
+        }
+        ++span;
+    }
+    return true;
+}
 
 static bool _rasterTranslucentRle(SwSurface* surface, SwRleData* rle, uint32_t color)
 {
@@ -232,6 +286,9 @@ static bool _rasterTranslucentRle(SwSurface* surface, SwRleData* rle, uint32_t c
         if (surface->compositor->method == CompositeMethod::AlphaMask) {
             return _translucentRleAlphaMask(surface, rle, color);
         }
+        if (surface->compositor->method == CompositeMethod::InvAlphaMask) {
+            return _translucentRleInvAlphaMask(surface, rle, color);
+        }
     }
     return _translucentRle(surface, rle, color);
 }
@@ -347,6 +404,26 @@ static bool _translucentImageAlphaMask(SwSurface* surface, uint32_t *img, uint32
     return true;
 }
 
+static bool _translucentImageInvAlphaMask(SwSurface* surface, uint32_t *img, uint32_t w, uint32_t h, uint32_t opacity, const SwBBox& region, const Matrix* invTransform)
+{
+#ifdef THORVG_LOG_ENABLED
+    printf("SW_ENGINE: Transformed Image Alpha Mask Composition\n");
+#endif
+    for (auto y = region.min.y; y < region.max.y; ++y) {
+        auto dst = &surface->buffer[y * surface->stride + region.min.x];
+        auto cmp = &surface->compositor->image.data[y * surface->stride + region.min.x];
+        float ey1 = y * invTransform->e12 + invTransform->e13;
+        float ey2 = y * invTransform->e22 + invTransform->e23;
+        for (auto x = region.min.x; x < region.max.x; ++x, ++dst, ++cmp) {
+            auto rX = static_cast<uint32_t>(roundf(x * invTransform->e11 + ey1));
+            auto rY = static_cast<uint32_t>(roundf(x * invTransform->e21 + ey2));
+            if (rX >= w || rY >= h) continue;
+            auto tmp = ALPHA_BLEND(img[rX + (rY * w)], ALPHA_MULTIPLY(opacity, surface->blender.alpha(*cmp)));  //TODO: need to use image's stride
+            *dst = tmp + ALPHA_BLEND(*dst, 255 - surface->blender.alpha(tmp));
+        }
+    }
+    return true;
+}
 
 static bool _rasterTranslucentImage(SwSurface* surface, uint32_t *img, uint32_t w, uint32_t h, uint32_t opacity, const SwBBox& region, const Matrix* invTransform)
 {
@@ -354,6 +431,9 @@ static bool _rasterTranslucentImage(SwSurface* surface, uint32_t *img, uint32_t
         if (surface->compositor->method == CompositeMethod::AlphaMask) {
             return _translucentImageAlphaMask(surface, img, w, h, opacity, region, invTransform);
         }
+        if (surface->compositor->method == CompositeMethod::InvAlphaMask) {
+            return _translucentImageInvAlphaMask(surface, img, w, h, opacity, region, invTransform);
+        }
     }
     return _translucentImage(surface, img, w, h, opacity, region, invTransform);
 }
@@ -399,12 +479,41 @@ static bool _translucentImageAlphaMask(SwSurface* surface, uint32_t *img, uint32
 }
 
 
+static bool _translucentImageInvAlphaMask(SwSurface* surface, uint32_t *img, uint32_t w, uint32_t h, uint32_t opacity, const SwBBox& region)
+{
+    auto buffer = surface->buffer + (region.min.y * surface->stride) + region.min.x;
+    auto h2 = static_cast<uint32_t>(region.max.y - region.min.y);
+    auto w2 = static_cast<uint32_t>(region.max.x - region.min.x);
+
+#ifdef THORVG_LOG_ENABLED
+    printf("SW_ENGINE: Image Alpha Mask Composition\n");
+#endif
+
+    auto sbuffer = img + (region.min.y * w) + region.min.x;
+    auto cbuffer = surface->compositor->image.data + (region.min.y * surface->stride) + region.min.x;   //compositor buffer
+
+    for (uint32_t y = 0; y < h2; ++y) {
+        auto dst = &buffer[y * surface->stride];
+        auto cmp = &cbuffer[y * surface->stride];
+        auto src = &sbuffer[y * w];   //TODO: need to use image's stride
+        for (uint32_t x = 0; x < w2; ++x, ++dst, ++src, ++cmp) {
+            auto ialpha = 255 - surface->blender.alpha(*cmp);
+            auto tmp = ALPHA_BLEND(*src, ialpha);
+            *dst = tmp + ALPHA_BLEND(*dst, 255 - surface->blender.alpha(tmp));
+        }
+    }
+    return true;
+}
+
 static bool _rasterTranslucentImage(SwSurface* surface, uint32_t *img, uint32_t w, uint32_t h, uint32_t opacity, const SwBBox& region)
 {
     if (surface->compositor) {
         if (surface->compositor->method == CompositeMethod::AlphaMask) {
             return _translucentImageAlphaMask(surface, img, w, h, opacity, region);
         }
+        if (surface->compositor->method == CompositeMethod::InvAlphaMask) {
+            return _translucentImageInvAlphaMask(surface, img, w, h, opacity, region);
+        }
     }
     return _translucentImage(surface, img, w, h, opacity, region);
 }

src/lib/tvgPaint.h

@@ -186,7 +186,7 @@ namespace tvg
                 cmpTarget->pImpl->render(renderer);
             }
 
-            if (cmp) renderer.beginComposite(cmp, CompositeMethod::AlphaMask, cmpTarget->pImpl->opacity);
+            if (cmp) renderer.beginComposite(cmp, cmpMethod, cmpTarget->pImpl->opacity);
 
             auto ret = smethod->render(renderer);