Shaders and triangle filling

CMakeLists.txt

@@ -15,6 +15,6 @@ add_executable(
         src/painter.cpp
         src/painter.hpp
         src/main.cpp
-
+        src/shaders.hpp
         src/shaders.cpp
 )

src/drawing_assets.cpp

@@ -61,4 +61,79 @@ void draw_line(Frame *frame, int x1, int y1, int x2, int y2, COLOR color) {
             frame->set_pixel(x, y, color);
         }
     }
-}
+}
+
+void fill_triangle(Frame *f, int x0, int y0, int x1, int y1, int x2, int y2, Shader const *shader) {
+// Отсортируем точки таким образом, чтобы выполнилось условие: y0 < y1 < y2
+    if (y1 < y0) {
+        std::swap(y1, y0);
+        std::swap(x1, x0);
+    }
+    if (y2 < y1) {
+        std::swap(y2, y1);
+        std::swap(x2, x1);
+    }
+    if (y1 < y0) {
+        std::swap(y1, y0);
+        std::swap(x1, x0);
+    }
+// Определяем номера строк пикселей, в которых располагаются точки треугольника
+    int Y0 = (int) (y0 + 0.5f);
+    int Y1 = (int) (y1 + 0.5f);
+    int Y2 = (int) (y2 + 0.5f);
+// Отсечение невидимой части треугольника
+    if (Y0 < 0) Y0 = 0;
+    else if (Y0 >= f->height) Y0 = f->height;
+    if (Y1 < 0) Y1 = 0;
+    else if (Y1 >= f->height) Y1 = f->height;
+    if (Y2 < 0) Y2 = 0;
+    else if (Y2 >= f->height) Y2 = f->height;
+// Рисование верхней части треугольника
+    for (float y = Y0 + 0.5f; y < Y1; y++) {
+        int X0 = (int) ((y - y0) / (y1 - y0) * (x1 - x0) + x0 + 0.5f);
+        int X1 = (int) ((y - y0) / (y2 - y0) * (x2 - x0) + x0 + 0.5f);
+        if (X0 > X1) std::swap(X0, X1);
+        if (X0 < 0) X0 = 0;
+        if (X1 > f->width) X1 = f->width;
+        for (int x = X0; x < X1; x++) {
+            f->set_pixel(x, y, shader->get_color(x + 0.5f, y));
+        }
+    }
+// Рисование нижней части треугольника
+    for (float y = Y1 + 0.5f; y < Y2; y++) {
+        int X0 = (int) ((y - y1) / (y2 - y1) * (x2 - x1) + x1 + 0.5f);
+        int X1 = (int) ((y - y0) / (y2 - y0) * (x2 - x0) + x0 + 0.5f);
+        if (X0 > X1) std::swap(X0, X1);
+        if (X0 < 0) X0 = 0;
+        if (X1 > f->width) X1 = f->width;
+        for (int x = X0; x < X1; x++) {
+            f->set_pixel(x, y, shader->get_color(x + 0.5f, y));
+        }
+    }
+}
+
+
+
+COLOR ColorFromHSV(double hue, double saturation, double value) {
+    int hi = int(floor(hue / 60)) % 6;
+    double f = hue / 60 - floor(hue / 60);
+    value = value * 255;
+    const auto v = (unsigned char) (value);
+    const auto p = (unsigned char) (value * (1 - saturation));
+    const auto q = (unsigned char) (value * (1 - f * saturation));
+    const auto t = (unsigned char) (value * (1 - (1 - f) * saturation));
+    switch (hi) {
+        case 0:
+            return COLOR{v, t, p};
+        case 1:
+            return COLOR{q, v, p};
+        case 2:
+            return COLOR{p, v, t};
+        case 3:
+            return COLOR{p, q, v};
+        case 4:
+            return COLOR{t, p, v};
+        default:
+            return COLOR{v, p, q};
+    }
+}

src/drawing_assets.hpp

@@ -114,4 +114,66 @@ void draw_polyline(Frame *frame, COLOR color, point_t ...points) {
         draw_polyline_<point_t...>::draw(frame, color, points...);
         draw_line(frame, draw_polyline_<point_t...>::last(points...), draw_polyline_<point_t...>::first(points...), color);
     }
-}
+}
+
+class Shader {
+public:
+    [[nodiscard]] virtual COLOR get_color(int x, int y) const = 0;
+};
+
+class MonoShader : public Shader {
+private:
+    COLOR color;
+public:
+    explicit MonoShader(COLOR color) : color{color} {}
+
+    [[nodiscard]] COLOR get_color(int x, int y) const override {
+        return this->color;
+    }
+};
+
+class BarycentricInterpolatorShader : public Shader {
+private:
+    int x0, y0, x1, y1, x2, y2, S;
+    COLOR C0, C1, C2;
+public:
+    BarycentricInterpolatorShader(float _x0, float _y0, float _x1, float _y1, float
+    _x2, float _y2, COLOR A0, COLOR A1, COLOR A2) :
+            x0(_x0), y0(_y0), x1(_x1), y1(_y1), x2(_x2), y2(_y2),
+            S((_y1 - _y2) * (_x0 - _x2) + (_x2 - _x1) * (_y0 - _y2)), C0(A0), C1(A1),
+            C2(A2) {
+    }
+
+    COLOR get_color(int x, int y) const override {
+// Барицентрическая интерполяция
+        float h0 = ((y1 - y2) * (x - x2) + (x2 - x1) * (y - y2)) / S;
+        float h1 = ((y2 - y0) * (x - x2) + (x0 - x2) * (y - y2)) / S;
+        float h2 = 1 - h0 - h1;
+        float r = h0 * C0.red + h1 * C1.red + h2 * C2.red;
+        float g = h0 * C0.green + h1 * C1.green + h2 * C2.green;
+        float b = h0 * C0.blue + h1 * C1.blue + h2 * C2.blue;
+        float a = h0 * C0.alpha + h1 * C1.alpha + h2 * C2.alpha;
+        return COLOR(r, g, b, a);
+    }
+};
+
+void fill_triangle(Frame *f, int x0, int y0, int x1, int y1, int x2, int y2, Shader const *shader);
+
+
+inline void fill_triangle(Frame *f, Point p0, Point p1, Point p2, Shader const *shader) {
+    fill_triangle(f, p0.x, p0.y, p1.x, p1.y, p2.x, p2.y, shader);
+}
+
+inline void fill_triangle(Frame *f, int x0, int y0, int x1, int y1, int x2, int y2, COLOR color) {
+    MonoShader s{color};
+    fill_triangle(f, x0, y0, x1, y1, x2, y2, &s);
+
+}
+
+
+inline void fill_triangle(Frame *f, Point p0, Point p1, Point p2, COLOR color) {
+    MonoShader s{color};
+    fill_triangle(f, p0.x, p0.y, p1.x, p1.y, p2.x, p2.y, &s);
+}
+
+COLOR ColorFromHSV(double hue, double saturation, double value);

src/painter.cpp

@@ -35,8 +35,42 @@ public:
     }
 };
 
+class Variant3S1Painter : public Painter {
+public:
+    void draw(PainterState *state, Frame *frame) const override {
+        int W = frame->width, H = frame->height;
+        // Размер рисунка возьмём меньше (7 / 8), чтобы он не касался границ экрана
+        float a = 7.0f / 8 * ((W < H) ? W - 1 : H - 1);
+        if (a < 1) return; // Если окно очень маленькое, то ничего не рисуем
+        float angle = state->angle; // Угол поворота
+        a = a / 2;
+
+        Point center{W / 2, H / 2};
+
+
+
+        // Рисуем описанную окружность
+        draw_circle(frame, center, a, COLOR(0, 0, 0));
+        draw_polyline(
+                frame, COLOR{0, 200, 0},
+                center.moved(0, a).rotated_around(center, 0 + angle),
+                center.moved(0, a).rotated_around(center, +2.0944 + angle),
+                center.moved(0, a).rotated_around(center, -2.0944 + angle)
+        );
+        draw_circle(frame, center, a / 2, COLOR(0, 200, 0));
+        draw_circle(frame, center.moved(0, a *2 / 3).rotated_around(center, angle), a / 6, COLOR(0, 200, 0));
+        draw_circle(frame, center.moved(0, a *2 / 3).rotated_around(center,  +2.0944 + angle), a / 6, COLOR(0, 200, 0));
+        draw_circle(frame, center.moved(0, a *2 / 3).rotated_around(center,  -2.0944 + angle), a / 6, COLOR(0, 200, 0));
+
+        // Рисуем пиксель, на который кликнул пользователь
+        if (state->clicked_pixel.x >= 0 && state->clicked_pixel.x < W &&
+            state->clicked_pixel.y >= 0 && state->clicked_pixel.y < H)
+            frame->set_pixel(state->clicked_pixel.x, state->clicked_pixel.y, {34, 175, 60}); // Пиксель зелёного цвета
+    }
+};
+
 static auto predefined_painters_ = std::make_tuple(
-        DemoPainter()
+        Variant3S1Painter()
 );
 
 Painter const *const predefined_painters[] = {

src/shaders.cpp

@@ -1,127 +1,26 @@
-#include <utility>
 #include "frame.hpp"
-#include "painter.hpp"
+#include "shaders.hpp"
 
-template<class ShaderClass>
+COLOR BarycentricInterpolator::get_color(int x, int y) const {
-void Triangle(Frame *f, float x0, float y0, float x1, float y1, float x2, float y2, COLOR color, ShaderClass *shader) {
-// Отсортируем точки таким образом, чтобы выполнилось условие: y0 < y1 < y2
-    if (y1 < y0) {
-        std::swap(y1, y0);
-        std::swap(x1, x0);
-    }
-    if (y2 < y1) {
-        std::swap(y2, y1);
-        std::swap(x2, x1);
-    }
-    if (y1 < y0) {
-        std::swap(y1, y0);
-        std::swap(x1, x0);
-    }
-// Определяем номера строк пикселей, в которых располагаются точки треугольника
-    int Y0 = (int) (y0 + 0.5f);
-    int Y1 = (int) (y1 + 0.5f);
-    int Y2 = (int) (y2 + 0.5f);
-// Отсечение невидимой части треугольника
-    if (Y0 < 0) Y0 = 0;
-    else if (Y0 >= f->height) Y0 = f->height;
-    if (Y1 < 0) Y1 = 0;
-    else if (Y1 >= f->height) Y1 = f->height;
-    if (Y2 < 0) Y2 = 0;
-    else if (Y2 >= f->height) Y2 = f->height;
-// Рисование верхней части треугольника
-    for (float y = Y0 + 0.5f; y < Y1; y++) {
-        int X0 = (int) ((y - y0) / (y1 - y0) * (x1 - x0) + x0 + 0.5f);
-        int X1 = (int) ((y - y0) / (y2 - y0) * (x2 - x0) + x0 + 0.5f);
-        if (X0 > X1) std::swap(X0, X1);
-        if (X0 < 0) X0 = 0;
-        if (X1 > f->width) X1 = f->width;
-        for (int x = X0; x < X1; x++) {
-// f(x + 0.5, y)
-            SetPixel(x, y, shader->getColor(x + 0.5f, y));
-        }
-    }
-// Рисование нижней части треугольника
-    for (float y = Y1 + 0.5f; y < Y2; y++) {
-        int X0 = (int) ((y - y1) / (y2 - y1) * (x2 - x1) + x1 + 0.5f);
-        int X1 = (int) ((y - y0) / (y2 - y0) * (x2 - x0) + x0 + 0.5f);
-        if (X0 > X1) std::swap(X0, X1);
-        if (X0 < 0) X0 = 0;
-        if (X1 > f->width) X1 = f->width;
-        for (int x = X0; x < X1; x++) {
-// f(x + 0.5, y)
-            SetPixel(x, y, shader->getColor(x + 0.5f, y));
-        }
-    }
-}
-
-class BarycentricInterpolator {
-    float x0, y0, x1, y1, x2, y2, S;
-    COLOR C0, C1, C2;
-public:
-    BarycentricInterpolator(float _x0, float _y0, float _x1, float _y1, float
-    _x2, float _y2, COLOR A0, COLOR A1, COLOR A2) :
-            x0(_x0), y0(_y0), x1(_x1), y1(_y1), x2(_x2), y2(_y2),
-            S((_y1 - _y2) * (_x0 - _x2) + (_x2 - _x1) * (_y0 - _y2)), C0(A0), C1(A1),
-            C2(A2) {
-    }
-
-    COLOR getColor(float x, float y) {
 // Барицентрическая интерполяция
-        float h0 = ((y1 - y2) * (x - x2) + (x2 - x1) * (y - y2)) / S;
+    float h0 = ((y1 - y2) * (x - x2) + (x2 - x1) * (y - y2)) / S;
-        float h1 = ((y2 - y0) * (x - x2) + (x0 - x2) * (y - y2)) / S;
+    float h1 = ((y2 - y0) * (x - x2) + (x0 - x2) * (y - y2)) / S;
-        float h2 = 1 - h0 - h1;
+    float h2 = 1 - h0 - h1;
-        float r = h0 * C0.red + h1 * C1.red + h2 * C2.red;
+    float r = h0 * C0.red + h1 * C1.red + h2 * C2.red;
-        float g = h0 * C0.green + h1 * C1.green + h2 * C2.green;
+    float g = h0 * C0.green + h1 * C1.green + h2 * C2.green;
-        float b = h0 * C0.blue + h1 * C1.blue + h2 * C2.blue;
+    float b = h0 * C0.blue + h1 * C1.blue + h2 * C2.blue;
-        float a = h0 * C0.alpha + h1 * C1.alpha + h2 * C2.alpha;
+    float a = h0 * C0.alpha + h1 * C1.alpha + h2 * C2.alpha;
-        return COLOR(r, g, b, a);
+    return COLOR(r, g, b, a);
-    }
-};
-
-
-class RadialBrush {
-    float cx, cy; // Центр прямоугольника
-    COLOR C0, C1; // Цвета радиальной заливки
-    float angle; // Начальный угол заливки
-public:
-    RadialBrush(float _x0, float _y0, float _x1, float _y1, COLOR A0, COLOR A1, float
-    _angle) :
-            cx((_x0 + _x1) / 2.0f), cy((_y0 + _y1) / 2.0f),
-            C0(A0), C1(A1), angle(_angle) {
-    }
-
-    COLOR getColor(float x, float y) {
-        double dx = (double) x - cx, dy = (double) y - cy;
-        double radius = sqrt(dx * dx + dy * dy);
-        float h0 = (sin(radius / 10 + angle) + 1.0f) / 2;
-        float h1 = 1 - h0;
-        float r = h0 * C0.red + h1 * C1.red;
-        float g = h0 * C0.green + h1 * C1.green;
-        float b = h0 * C0.blue + h1 * C1.blue;
-        return COLOR(r, g, b);
-    }
-};
-
-COLOR ColorFromHSV(double hue, double saturation, double value) {
-    int hi = int(floor(hue / 60)) % 6;
-    double f = hue / 60 - floor(hue / 60);
-    value = value * 255;
-    const auto v = (unsigned char) (value);
-    const auto p = (unsigned char) (value * (1 - saturation));
-    const auto q = (unsigned char) (value * (1 - f * saturation));
-    const auto t = (unsigned char) (value * (1 - (1 - f) * saturation));
-    switch (hi) {
-        case 0:
-            return COLOR{v, t, p};
-        case 1:
-            return COLOR{q, v, p};
-        case 2:
-            return COLOR{p, v, t};
-        case 3:
-            return COLOR{p, q, v};
-        case 4:
-            return COLOR{t, p, v};
-        default:
-            return COLOR{v, p, q};
-    }
 }
+
+
+COLOR RadialBrush::get_color(int x, int y) const {
+    double dx = (double) x - cx, dy = (double) y - cy;
+    double radius = sqrt(dx * dx + dy * dy);
+    float h0 = (sin(radius / 10 + angle) + 1.0f) / 2;
+    float h1 = 1 - h0;
+    float r = h0 * C0.red + h1 * C1.red;
+    float g = h0 * C0.green + h1 * C1.green;
+    float b = h0 * C0.blue + h1 * C1.blue;
+    return COLOR(r, g, b);
+}

src/shaders.hpp

@@ -0,0 +1,35 @@
+#pragma once
+
+#include "painter.hpp"
+#include "drawing_assets.hpp"
+
+class BarycentricInterpolator : public Shader {
+private:
+    float x0, y0, x1, y1, x2, y2, S;
+    COLOR C0, C1, C2;
+public:
+    inline BarycentricInterpolator(float _x0, float _y0, float _x1, float _y1, float _x2, float _y2, COLOR A0, COLOR A1, COLOR A2) :
+            x0(_x0), y0(_y0), x1(_x1), y1(_y1), x2(_x2), y2(_y2),
+            S((_y1 - _y2) * (_x0 - _x2) + (_x2 - _x1) * (_y0 - _y2)),
+            C0(A0), C1(A1), C2(A2) {}
+
+    inline BarycentricInterpolator(Point p0, Point p1, Point p2, COLOR A0, COLOR A1, COLOR A2) :
+            BarycentricInterpolator(p0.x, p0.y, p1.x, p1.y, p2.x, p2.y, A0, A1, A2) {}
+
+    COLOR get_color(int x, int y) const override;
+};
+
+
+class RadialBrush : public Shader {
+private:
+    float cx, cy;
+    COLOR C0, C1;
+    float angle;
+public:
+    RadialBrush(float _x0, float _y0, float _x1, float _y1, COLOR A0, COLOR A1, float _angle) :
+            cx((_x0 + _x1) / 2.0f), cy((_y0 + _y1) / 2.0f),
+            C0(A0), C1(A1), angle(_angle) {}
+
+
+    COLOR get_color(int x, int y) const override;
+};