gl_engine: remove the outdated tesseletion mechanics

After introducing Triangle Fan-like Triangulation there is no necessary to have heavy and complex tessellator
All unused entities are removed

src/common/tvgArray.h

@@ -186,35 +186,10 @@ struct Array
         return count == reserved;
     }
 
-    template<class COMPARE> void sort()
-    {
-        qsort<COMPARE>(data, 0, (int32_t)(count - 1));
-    }
-
     ~Array()
     {
         tvg::free(data);
     }
-
-private:
-    template<class COMPARE>
-    void qsort(T* arr, int32_t low, int32_t high)
-    {
-        if (low < high) {
-            auto i = low;
-            auto j = high;
-            auto tmp = arr[low];
-            while (i < j) {
-                while (i < j && !COMPARE{}(arr[j], tmp)) --j;
-                if (i < j) arr[i++] = arr[j];
-                while (i < j && COMPARE{}(arr[i], tmp)) ++i;
-                if (i < j) arr[j--] = arr[i];
-            }
-            arr[i] = tmp;
-            qsort<COMPARE>(arr, low, i - 1);
-            qsort<COMPARE>(arr, i + 1, high);
-        }
-    }
 };
 
 }

src/renderer/gl_engine/meson.build

@@ -2,7 +2,6 @@ source_file = [
    'tvgGl.h',
    'tvgGlCommon.h',
    'tvgGlGpuBuffer.h',
-   'tvgGlList.h',
    'tvgGlProgram.h',
    'tvgGlRenderer.h',
    'tvgGlRenderPass.h',

src/renderer/gl_engine/tvgGlCommon.h

@@ -23,31 +23,29 @@
 #ifndef _TVG_GL_COMMON_H_
 #define _TVG_GL_COMMON_H_
 
-#include <assert.h>
+#include <cassert>
 #include "tvgGl.h"
 #include "tvgRender.h"
 #include "tvgMath.h"
 
 #define MIN_GL_STROKE_WIDTH 1.0f
 
-#define MVP_MATRIX(w, h) \
-    float mvp[4*4] = { \
-        2.f / w, 0.0, 0.0f, 0.0f, \
-        0.0, -2.f / h, 0.0f, 0.0f, \
-        0.0f, 0.0f, -1.f, 0.0f, \
-        -1.f, 1.f, 0.0f, 1.0f \
+#define MVP_MATRIX(w, h)                \
+    float mvp[4*4] = {                  \
+        2.f / w,      0.0,  0.0f, 0.0f, \
+        0.0,     -2.f / h,  0.0f, 0.0f, \
+        0.0f,        0.0f, -1.0f, 0.0f, \
+        -1.f,         1.f,  0.0f, 1.0f  \
     };
 
-#define MULTIPLY_MATRIX(A, B, transform) \
-    for(auto i = 0; i < 4; ++i) \
-    { \
-        for(auto j = 0; j < 4; ++j) \
-        { \
-            float sum = 0.0; \
-            for (auto k = 0; k < 4; ++k) \
+#define MULTIPLY_MATRIX(A, B, transform)    \
+    for(auto i = 0; i < 4; ++i) {           \
+        for(auto j = 0; j < 4; ++j) {       \
+            float sum = 0.0;                \
+            for (auto k = 0; k < 4; ++k)    \
                 sum += A[k*4+i] * B[j*4+k]; \
-            transform[j*4+i] = sum; \
-        } \
+            transform[j*4+i] = sum;         \
+        }                                   \
     }
 
 /**
@@ -61,24 +59,24 @@
  */
 
 // All GPU use 4x4 matrix with column major order
-#define GET_MATRIX44(mat3, mat4)    \
-    do {                            \
-        mat4[0] = mat3.e11;         \
-        mat4[1] = mat3.e21;         \
-        mat4[2] = 0;                \
-        mat4[3] = mat3.e31;         \
-        mat4[4] = mat3.e12;         \
-        mat4[5] = mat3.e22;         \
-        mat4[6] = 0;                \
-        mat4[7] = mat3.e32;         \
-        mat4[8] = 0;                \
-        mat4[9] = 0;                \
-        mat4[10] = 1;               \
-        mat4[11] = 0;               \
-        mat4[12] = mat3.e13;        \
-        mat4[13] = mat3.e23;        \
-        mat4[14] = 0;               \
-        mat4[15] = mat3.e33;        \
+#define GET_MATRIX44(mat3, mat4) \
+    do {                         \
+        mat4[0] = mat3.e11;      \
+        mat4[1] = mat3.e21;      \
+        mat4[2] = 0;             \
+        mat4[3] = mat3.e31;      \
+        mat4[4] = mat3.e12;      \
+        mat4[5] = mat3.e22;      \
+        mat4[6] = 0;             \
+        mat4[7] = mat3.e32;      \
+        mat4[8] = 0;             \
+        mat4[9] = 0;             \
+        mat4[10] = 1;            \
+        mat4[11] = 0;            \
+        mat4[12] = mat3.e13;     \
+        mat4[13] = mat3.e23;     \
+        mat4[14] = 0;            \
+        mat4[15] = mat3.e33;     \
     } while (false)
 
 
@@ -115,7 +113,6 @@ struct GlGeometry
 {
     bool tesselate(const RenderShape& rshape, RenderUpdateFlag flag);
     bool tesselate(const RenderSurface* image, RenderUpdateFlag flag);
-    void disableVertex(uint32_t location);
     bool draw(GlRenderTask* task, GlStageBuffer* gpuBuffer, RenderUpdateFlag flag);
     GlStencilMode getStencilMode(RenderUpdateFlag flag);
     RenderRegion getBounds() const;

src/renderer/gl_engine/tvgGlGeometry.cpp

@@ -108,12 +108,6 @@ bool GlGeometry::tesselate(const RenderSurface* image, RenderUpdateFlag flag)
 }
 
 
-void GlGeometry::disableVertex(uint32_t location)
-{
-    GL_CHECK(glDisableVertexAttribArray(location));
-}
-
-
 bool GlGeometry::draw(GlRenderTask* task, GlStageBuffer* gpuBuffer, RenderUpdateFlag flag)
 {
     if (flag == RenderUpdateFlag::None) return false;

src/renderer/gl_engine/tvgGlList.h

@@ -1,90 +0,0 @@
-/*
- * Copyright (c) 2023 - 2025 the ThorVG project. All rights reserved.
-
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
-
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
-
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-#ifndef _TVG_LIST_H_
-#define _TVG_LIST_H_
-
-namespace tvg {
-
-template<typename T>
-struct LinkedList
-{
-    T *head = nullptr;
-    T *tail = nullptr;
-
-    LinkedList() = default;
-    LinkedList(T *head, T *tail) : head(head), tail(tail)
-    {
-    }
-
-    template<T *T::*Prev, T *T::*Next>
-    static void insert(T *t, T *prev, T *next, T **head, T **tail)
-    {
-        t->*Prev = prev;
-        t->*Next = next;
-
-        if (prev) {
-            prev->*Next = t;
-        } else if (head) {
-            *head = t;
-        }
-
-        if (next) {
-            next->*Prev = t;
-        } else if (tail) {
-            *tail = t;
-        }
-    }
-
-    template<T *T::*Prev, T *T::*Next>
-    static void remove(T *t, T **head, T **tail)
-    {
-        if (t->*Prev) {
-            t->*Prev->*Next = t->*Next;
-        } else if (head) {
-            *head = t->*Next;
-        }
-
-        if (t->*Next) {
-            t->*Next->*Prev = t->*Prev;
-        } else if (tail) {
-            *tail = t->*Prev;
-        }
-
-        t->*Prev = t->*Next = nullptr;
-    }
-
-    template <T* T::*Next>
-    static bool contains(T *t, T **head, T **tail) {
-        for (T *it = *head; it; it = it->*Next) {
-            if (it == t) {
-                return true;
-            }
-        }
-
-        return false;
-    }
-};
-
-}
-
-#endif // _TVG_LIST_H_

src/renderer/gl_engine/tvgGlTessellator.h

@@ -23,51 +23,11 @@
 #ifndef _TVG_GL_TESSELLATOR_H_
 #define _TVG_GL_TESSELLATOR_H_
 
-#include <cstdint>
 #include "tvgGlCommon.h"
 
 namespace tvg
 {
 
-class ObjectHeap;
-struct Vertex;
-struct Edge;
-struct Polygon;
-struct MonotonePolygon;
-struct VertexList;
-struct ActiveEdgeList;
-struct RenderShape;
-
-class Tessellator final
-{
-public:
-    Tessellator(GlGeometryBuffer* buffer);
-    ~Tessellator();
-    void tessellate(const Array<const RenderShape*> &shapes);
-
-private:
-    void visitShape(const RenderPath& path);
-    void buildMesh();
-    void mergeVertices();
-    bool simplifyMesh();
-    bool tessMesh();
-    bool matchFillRule(int32_t winding);
-    Edge *makeEdge(Vertex* p1, Vertex* p2);
-    bool checkIntersection(Edge* left, Edge* right, ActiveEdgeList* ael, Vertex** current);
-    bool splitEdge(Edge* edge, Vertex* v, ActiveEdgeList* ael, Vertex** current);
-    bool intersectPairEdge(Edge* left, Edge* right, ActiveEdgeList* ael, Vertex** current);
-    Polygon *makePoly(Vertex* v, int32_t winding);
-    void emitPoly(MonotonePolygon* poly);
-    void emitTriangle(Vertex* p1, Vertex* p2, Vertex* p3);
-
-    FillRule fillRule = FillRule::NonZero;
-    ObjectHeap* pHeap;
-    Array<VertexList*> outlines;
-    VertexList* pMesh;
-    Polygon* pPolygon;
-    GlGeometryBuffer* buffer;
-};
-
 class Stroker
 {
     struct State
@@ -79,7 +39,6 @@ class Stroker
     };
 public:
     Stroker(GlGeometryBuffer* buffer, const Matrix& matrix);
-    ~Stroker() = default;
     void stroke(const RenderShape *rshape, const RenderPath& path);
     RenderRegion bounds() const;
 
@@ -147,7 +106,6 @@ class BWTessellator
 {
 public:
     BWTessellator(GlGeometryBuffer* buffer);
-    ~BWTessellator() = default;
     void tessellate(const RenderPath& path, const Matrix& matrix);
     RenderRegion bounds() const;