forming the skeleton

src/preview.h

@@ -1,26 +1,50 @@
 #pragma once
 
-#include "texture.h"
+#include "resources.h"
+#include "input.h"
 
-static const ivec2 PREVIEW_SIZE = {1280, 720};
+static const ivec2 PREVIEW_SIZE = {960, 720};
+static const ivec2 PREVIEW_CENTER = {0, 0};
 
-#define PREVIEW_ZOOM_MIN 0
+#define PREVIEW_ZOOM_MIN 1
 #define PREVIEW_ZOOM_MAX 400
-#define PREVIEW_GRID_MIN 0
-#define PREVIEW_GRID_MAX 20
+#define PREVIEW_GRID_MIN 1
+#define PREVIEW_GRID_MAX 50
+#define PREVIEW_ZOOM_STEP 10
+
+static const f32 PREVIEW_AXIS_VERTICES[] = 
+{
+    -1.0f,  0.0f,
+    1.0f,   0.0f,
+    0.0f,   -1.0f,
+    0.0f,   1.0f
+};
 
 struct Preview
 {
     GLuint texture;
     GLuint fbo;
     GLuint rbo;
-    bool isGrid;
+    GLuint gridVAO;
+    GLuint gridVBO;
+    GLuint axisVAO;
+    GLuint axisVBO;
+    Input* input;
+    Resources* resources;
+    bool isGrid = false;
+    bool isAxis = true;
+    ivec2 viewport = PREVIEW_SIZE;
     f32 zoom = 100;
+    vec2 pan = PREVIEW_CENTER;
     ivec2 gridSize = {10, 10};
-    vec4 color = {0.69, 0.69, 0.69, 1.0f};
-    vec4 gridColor = {0.35, 0.35, 0.35, 1.0f};
+    ivec2 oldGridSize = {-1, -1};
+    s32 gridVertexCount = -1;
+    vec4 backgroundColor = {0.113, 0.184, 0.286, 1.0f};
+    vec4 gridColor = {1.0, 1.0, 1.0, 0.125f};
+    vec4 axisColor = {1.0, 1.0, 1.0, 0.5f};
 };
 
-void preview_init(Preview* self);
+void preview_init(Preview* self, Resources* resources, Input* input);
 void preview_draw(Preview* self);
+void preview_tick(Preview* self);
 void preview_free(Preview* self);