1 files changed, 98 insertions, 0 deletions
diff --git a/Canvas/Canvas.cpp b/Canvas/Canvas.cpp
new file mode 100644
index 0000000..6034633
--- /dev/null
+++ b/Canvas/Canvas.cpp
@@ -0,0 +1,98 @@
+//
+// Created by saintruler on 05.05.19.
+//
+#include "Canvas.h"
+
+Canvas::Canvas(int width, int height, Point *points, int nPoints)
+{
+    float vertices[] = {
+            // positions        // colors           // texture coords
+            1.f,  1.f, 0.0f,    1.0f, 0.0f, 0.0f,   1.0f, 1.0f, // top right
+            1.f, -1.f, 0.0f,    0.0f, 1.0f, 0.0f,   1.0f, 0.0f, // bottom right
+            -1.f, -1.f, 0.0f,   0.0f, 0.0f, 1.0f,   0.0f, 0.0f, // bottom left
+            -1.f,  1.f, 0.0f,   1.0f, 1.0f, 0.0f,   0.0f, 1.0f  // top left
+    };
+
+    int indices[] = {
+            0, 1, 3, // first triangle
+            1, 2, 3  // second triangle
+    };
+
+    glGenVertexArrays(1, &VAO);
+    glGenBuffers(1, &VBO);
+    glGenBuffers(1, &EBO);
+
+    glBindVertexArray(VAO);
+
+    glBindBuffer(GL_ARRAY_BUFFER, VBO);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
+
+    // position attribute
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
+    glEnableVertexAttribArray(0);
+    // color attribute
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float)));
+    glEnableVertexAttribArray(1);
+    // texture coord attribute
+    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float)));
+    glEnableVertexAttribArray(2);
+
+    this->width = width;
+    this->height = height;
+    this->nPoints = nPoints;
+
+    this->points = points;
+    canvas = (unsigned char*) malloc(width * height * 3);
+    glGenTextures(1, &texture);
+}
+
+void Canvas::SetPixel(int x, int y, Color color)
+{
+    canvas[y * width * 3 + x * 3 + 0] = color.r;
+    canvas[y * width * 3 + x * 3 + 1] = color.g;
+    canvas[y * width * 3 + x * 3 + 2] = color.b;
+
+    UpdateTexture();
+}
+
+void Canvas::UpdateTexture()
+{
+    // all upcoming GL_TEXTURE_2D operations now have effect on this texture object
+    glBindTexture(GL_TEXTURE_2D, texture);
+
+    // set texture wrapping to GL_REPEAT (default wrapping method)
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+
+    // set texture filtering parameters
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+    generate_canvas(width, height, canvas, points, nPoints);
+
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, width, 0, GL_RGB, GL_UNSIGNED_BYTE, canvas);
+    glGenerateMipmap(GL_TEXTURE_2D);
+}
+
+void Canvas::DrawTexture()
+{
+    UpdateTexture();
+
+    glBindTexture(GL_TEXTURE_2D, texture);
+    shader.use();
+
+    glBindVertexArray(VAO);
+    glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
+}
+
+void Canvas::DeleteCanvas()
+{
+    glDeleteVertexArrays(1, &VAO);
+    glDeleteBuffers(1, &VBO);
+    glDeleteBuffers(1, &EBO);
+
+    delete[] canvas;
+}