Add support for rendering raster images

.gitignore

@@ -0,0 +1,7 @@
+# Ignore build dirs
+/build
+/cmake-build-*
+
+# Ignore IDE specific dirs
+*.idea
+**/.vscode

example/CMakeLists.txt

@@ -2,7 +2,12 @@ cmake_minimum_required(VERSION 3.3)
 
 set(CMAKE_C_STANDARD 99)
 
-project(smiley C)
+project(examples C)
 
 add_executable(smiley smiley.c)
 target_link_libraries(smiley plutovg m)
+
+add_executable(texture texture.c)
+target_link_libraries(texture plutovg m)
+
+file(COPY assets DESTINATION ${CMAKE_CURRENT_BINARY_DIR})

example/texture.c

@@ -0,0 +1,82 @@
+#include "plutovg.h"
+
+#define STB_IMAGE_IMPLEMENTATION
+#include "stb_image.h"
+
+#define NUM_TEXTURES 4
+
+int main(void) {
+    // PlutoVG
+    const int canvas_width = 900;
+    const int canvas_height = 900;
+    plutovg_surface_t *surface = plutovg_surface_create(canvas_width, canvas_height);
+    plutovg_t *pluto = plutovg_create(surface);
+
+    // Draw raster textures in 4 corners
+    int positions[NUM_TEXTURES][2] = {{-1, -1},
+                                      {1,  -1},
+                                      {-1, 1},
+                                      {1,  1}};
+    for (int i = 0; i < NUM_TEXTURES; ++i)
+    {
+        char filename[PATH_MAX];
+        sprintf(filename, "assets/texture%d.png", i + 1);
+
+        int width, height, channels;
+        unsigned char *image_data = stbi_load(filename, &width, &height, &channels, 0);
+
+        if (!image_data) {
+            fprintf(stderr, "Error loading textures: %s\n", stbi_failure_reason());
+            return 1;
+        }
+
+        const int x = positions[i][0] * width / 2;
+        const int y = positions[i][1] * height / 2;
+
+        plutovg_save(pluto);
+        plutovg_image(pluto, x, y, image_data, width, height, channels);
+        plutovg_restore(pluto);
+
+        stbi_image_free(image_data);
+    }
+
+    // Draw vector shapes on top of the textures
+    const double center_x = canvas_width * 0.5;
+    const double center_y = canvas_height * 0.5;
+    const double face_radius = canvas_width * 0.25;
+    const double eye_radius = face_radius * 0.1;
+    const double mouth_radius = face_radius * 0.7;
+    const double eye_offset_x = face_radius * 0.35;
+    const double eye_offset_y = face_radius * 0.3;
+    const double eye_x = center_x - eye_offset_x;
+    const double eye_y = center_y - eye_offset_y;
+
+    const double pi = 3.14159265358979323846;
+
+    plutovg_save(pluto);
+    plutovg_arc(pluto, center_x, center_y, face_radius, 0, 2 * pi, 0);
+    plutovg_set_rgb(pluto, 1, 1, 0);
+    plutovg_fill_preserve(pluto);
+    plutovg_set_rgb(pluto, 0, 0, 0);
+    plutovg_set_line_width(pluto, 10);
+    plutovg_stroke(pluto);
+    plutovg_restore(pluto);
+
+    plutovg_save(pluto);
+    plutovg_arc(pluto, eye_x, eye_y, eye_radius, 0, 2 * pi, 0);
+    plutovg_arc(pluto, center_x + eye_offset_x, eye_y, eye_radius, 0, 2 * pi, 0);
+    plutovg_fill(pluto);
+    plutovg_restore(pluto);
+
+    plutovg_save(pluto);
+    plutovg_arc(pluto, center_x, center_y, mouth_radius, 0, pi, 0);
+    plutovg_set_line_width(pluto, 10);
+    plutovg_stroke(pluto);
+    plutovg_restore(pluto);
+
+    plutovg_surface_write_to_png(surface, "texture.png");
+    plutovg_surface_destroy(surface);
+    plutovg_destroy(pluto);
+
+    return 0;
+}

include/plutovg.h

@@ -302,6 +302,8 @@ void plutovg_rel_quad_to(plutovg_t* pluto, double dx1, double dy1, double dx2, d
 void plutovg_rel_cubic_to(plutovg_t* pluto, double dx1, double dy1, double dx2, double dy2, double dx3, double dy3);
 
 void plutovg_rect(plutovg_t* pluto, double x, double y, double w, double h);
+void plutovg_pixel(plutovg_t* pluto, int x, int y);
+void plutovg_image(plutovg_t* pluto, int x, int y, unsigned char* data, int w, int h, int c);
 void plutovg_round_rect(plutovg_t* pluto, double x, double y, double w, double h, double rx, double ry);
 void plutovg_ellipse(plutovg_t* pluto, double cx, double cy, double rx, double ry);
 void plutovg_circle(plutovg_t* pluto, double cx, double cy, double r);

source/plutovg.c

@@ -668,6 +668,32 @@ void plutovg_rect(plutovg_t* pluto, double x, double y, double w, double h)
     plutovg_path_add_rect(pluto->path, x, y, w, h);
 }
 
+void plutovg_pixel(plutovg_t* pluto, int x, int y)
+{
+    plutovg_path_add_rect(pluto->path, x, y, 1, 1);
+}
+
+void plutovg_image(plutovg_t* pluto, int x, int y, unsigned char* data, int w, int h, int c)
+{
+    const int canvas_h = pluto->surface->height;
+    const int canvas_w = pluto->surface->width;
+
+    for (int i = plutovg_max(0, -y); i < plutovg_min(h, canvas_h - y); ++i) {
+        for (int j = plutovg_max(0, -x); j < plutovg_min(w, canvas_w - x); ++j) {
+            plutovg_pixel(pluto, j + x, i + y);
+
+            unsigned char *pixel_offset = data + (j + w * i) * c;
+            const double r = pixel_offset[0] / 255.0;
+            const double g = pixel_offset[1] / 255.0;
+            const double b = pixel_offset[2] / 255.0;
+            const double a = c >= 4 ? pixel_offset[3] / 255.0 : 1.0;
+
+            plutovg_set_rgba(pluto, r, g, b, a);
+            plutovg_fill(pluto);
+        }
+    }
+}
+
 void plutovg_round_rect(plutovg_t* pluto, double x, double y, double w, double h, double rx, double ry)
 {
     plutovg_path_add_round_rect(pluto->path, x, y, w, h, rx, ry);