commit 0081d6f2d6c3e20c7bb6e37ad4984f9ba3a39fbb
parent f258d192d0be5a79c9c4c28bf5010eec187dd33f
Author: amin <dev@aminmesbah.com>
Date: Sat, 5 Aug 2017 08:32:48 +0000
Add the ability to pan.
Uses simple delta x and delta y values to offsets the location of each
rendered pixel. Note that this doesn't play nice with trace mode.
FossilOrigin-Name: 98baf0a02db9dbb484a44b6ff33ec31e09ebc8c6182586f9978aa803f76bf2bc
Diffstat:
4 files changed, 102 insertions(+), 22 deletions(-)
diff --git a/README.md b/README.md
@@ -10,6 +10,9 @@ efficiently calculate the forces acting on each star.
### Keyboard Shortcuts
+- `WASD`: Pan.
+- `Arrow Keys`: Slow Pan.
+- `Home`: Center View.
- `b`: Toggle bounding box rendering.
- `f`: Toggle brute-force mode. Stars turn blue when this mode is active, and
gravitational attraction is calculated for every single pair of stars. The
diff --git a/src/platform_sdl.c b/src/platform_sdl.c
@@ -204,6 +204,47 @@ int main(int argc, char *argv[])
SDL_PumpEvents();
dimension = sdl_get_window_dimension(window);
+
+ const uint8_t *keystate = SDL_GetKeyboardState(0);
+
+ if (keystate[SDL_SCANCODE_A])
+ {
+ sim_state.view.dx += 5;
+ }
+ if (keystate[SDL_SCANCODE_D])
+ {
+ sim_state.view.dx -= 5;
+ }
+ if (keystate[SDL_SCANCODE_W])
+ {
+ sim_state.view.dy += 5;
+ }
+ if (keystate[SDL_SCANCODE_S])
+ {
+ sim_state.view.dy -= 5;
+ }
+ if (keystate[SDL_SCANCODE_LEFT])
+ {
+ sim_state.view.dx++;
+ }
+ if (keystate[SDL_SCANCODE_RIGHT])
+ {
+ sim_state.view.dx--;
+ }
+ if (keystate[SDL_SCANCODE_UP])
+ {
+ sim_state.view.dy++;
+ }
+ if (keystate[SDL_SCANCODE_DOWN])
+ {
+ sim_state.view.dy--;
+ }
+ if (keystate[SDL_SCANCODE_HOME])
+ {
+ sim_state.view.dx = 0;
+ sim_state.view.dy = 0;
+ }
+
struct OffscreenBuffer buffer;
// WARNING: these pointers are aliased until the end of the
// loop
diff --git a/src/star_garden.c b/src/star_garden.c
@@ -18,11 +18,15 @@ void sim_init(struct SimState *sim_state, int field_width, int field_height)
}
sim_state->num_stars = NUM_STARS;
+
sim_state->bounding_box.center_x = field_width / 2;
sim_state->bounding_box.center_y = field_height / 2;
sim_state->bounding_box.side_length_x = 0;
sim_state->bounding_box.side_length_y = 0;
+ sim_state->view.dx = 0;
+ sim_state->view.dy = 0;
+
float min_x = field_width / 2;
float max_x = field_width / 2;
float min_y = field_height / 2;
@@ -177,6 +181,8 @@ void sim_render(struct OffscreenBuffer *buffer, float dt, struct SimState *sim_s
return;
}
+ float dx = sim_state->view.dx;
+ float dy = sim_state->view.dy;
int num_stars = sim_state->num_stars;
struct Star *stars = sim_state->stars;
struct QuadTree *qt = sim_state->qt;
@@ -187,8 +193,8 @@ void sim_render(struct OffscreenBuffer *buffer, float dt, struct SimState *sim_s
{
sim_set_pixel(
buffer,
- stars[i].x + (sinf(stars[i].angle) * stars[i].speed) * dt,
- stars[i].y - (cosf(stars[i].angle) * stars[i].speed) * dt,
+ (stars[i].x + (sinf(stars[i].angle) * stars[i].speed) * dt) + dx,
+ (stars[i].y - (cosf(stars[i].angle) * stars[i].speed) * dt) + dy,
COLOR_CYAN);
}
}
@@ -198,19 +204,19 @@ void sim_render(struct OffscreenBuffer *buffer, float dt, struct SimState *sim_s
{
sim_set_pixel(
buffer,
- stars[i].x + (sinf(stars[i].angle) * stars[i].speed) * dt,
- stars[i].y - (cosf(stars[i].angle) * stars[i].speed) * dt,
+ (stars[i].x + (sinf(stars[i].angle) * stars[i].speed) * dt) + dx,
+ (stars[i].y - (cosf(stars[i].angle) * stars[i].speed) * dt) + dy,
stars[i].color);
}
}
if (RENDER_GRID)
{
- sim_grid_render(buffer, qt->root, COLOR_GREEN);
+ sim_grid_render(buffer, qt->root, COLOR_GREEN, dx, dy);
}
if (RENDER_BOUNDING_BOX)
{
- sim_bounding_box_render(buffer, &sim_state->bounding_box, COLOR_RED);
+ sim_bounding_box_render(buffer, &sim_state->bounding_box, COLOR_RED, dx, dy);
}
}
@@ -237,7 +243,7 @@ void sim_set_pixel(struct OffscreenBuffer *buffer, uint32_t x, uint32_t y, uint3
}
-void sim_grid_render(struct OffscreenBuffer *buffer, struct QuadTreeNode *node, uint32_t color)
+void sim_grid_render(struct OffscreenBuffer *buffer, struct QuadTreeNode *node, uint32_t color, float dx, float dy)
{
if (!buffer)
{
@@ -251,25 +257,25 @@ void sim_grid_render(struct OffscreenBuffer *buffer, struct QuadTreeNode *node,
x <= (node->cell->center_x + node->cell->distance_x);
++x)
{
- sim_set_pixel(buffer, x, node->cell->center_y, color);
+ sim_set_pixel(buffer, x + dx, node->cell->center_y + dy, color);
}
for (int y = (node->cell->center_y - node->cell->distance_y);
y <= (node->cell->center_y + node->cell->distance_y);
++y)
{
- sim_set_pixel(buffer, node->cell->center_x, y, color);
+ sim_set_pixel(buffer, node->cell->center_x + dx, y + dy, color);
}
- sim_grid_render(buffer, node->ne, color);
- sim_grid_render(buffer, node->nw, color);
- sim_grid_render(buffer, node->sw, color);
- sim_grid_render(buffer, node->se, color);
+ sim_grid_render(buffer, node->ne, color, dx, dy);
+ sim_grid_render(buffer, node->nw, color, dx, dy);
+ sim_grid_render(buffer, node->sw, color, dx, dy);
+ sim_grid_render(buffer, node->se, color, dx, dy);
}
}
-void sim_bounding_box_render(struct OffscreenBuffer *buffer, struct SimBounds *bounding_box, uint32_t color)
+void sim_bounding_box_render(struct OffscreenBuffer *buffer, struct SimBounds *bounding_box, uint32_t color, float dx, float dy)
{
if (!buffer)
{
@@ -284,13 +290,20 @@ void sim_bounding_box_render(struct OffscreenBuffer *buffer, struct SimBounds *b
x <= bounding_box->center_x + reticle_radius;
x++)
{
- sim_set_pixel(buffer, x, bounding_box->center_y, color);
+ sim_set_pixel(
+ buffer, x + dx,
+ bounding_box->center_y + dy,
+ color);
}
for (int y = bounding_box->center_y - reticle_radius;
y <= bounding_box->center_y + reticle_radius;
y++)
{
- sim_set_pixel(buffer, bounding_box->center_x, y, color);
+ sim_set_pixel(
+ buffer,
+ bounding_box->center_x + dx,
+ y + dy,
+ color);
}
float half_length_x = bounding_box->side_length_x / 2;
@@ -300,16 +313,32 @@ void sim_bounding_box_render(struct OffscreenBuffer *buffer, struct SimBounds *b
x <= (bounding_box->center_x + half_length_x);
++x)
{
- sim_set_pixel(buffer, x, bounding_box->center_y - half_length_y, color);
- sim_set_pixel(buffer, x, bounding_box->center_y + half_length_y, color);
+ sim_set_pixel(
+ buffer,
+ x + dx,
+ bounding_box->center_y - half_length_y + dy,
+ color);
+ sim_set_pixel(
+ buffer,
+ x + dx,
+ bounding_box->center_y + half_length_y + dy,
+ color);
}
for (int y = (bounding_box->center_y - half_length_y);
y <= (bounding_box->center_y + half_length_y);
++y)
{
- sim_set_pixel(buffer, bounding_box->center_x - half_length_x, y, color);
- sim_set_pixel(buffer, bounding_box->center_x + half_length_x, y, color);
+ sim_set_pixel(
+ buffer,
+ bounding_box->center_x - half_length_x + dx,
+ y + dy,
+ color);
+ sim_set_pixel(
+ buffer,
+ bounding_box->center_x + half_length_x + dx,
+ y + dy,
+ color);
}
}
}
diff --git a/src/star_garden.h b/src/star_garden.h
@@ -62,10 +62,17 @@ struct SimBounds
float side_length_y;
};
+struct SimView
+{
+ float dx;
+ float dy;
+};
+
struct SimState
{
int num_stars;
struct SimBounds bounding_box;
+ struct SimView view;
struct QuadTree *qt;
struct Star stars[NUM_STARS];
};
@@ -84,8 +91,8 @@ void sim_update(struct SimState *sim_state, int field_width, int field_height);
void sim_bounding_box_update(struct SimBounds *bounds, float min_x, float min_y, float max_x, float max_y);
void sim_render(struct OffscreenBuffer *buffer, float dt, struct SimState *sim_state);
void sim_set_pixel(struct OffscreenBuffer *buffer, uint32_t x, uint32_t y, uint32_t color);
-void sim_bounding_box_render(struct OffscreenBuffer *buffer, struct SimBounds *bounding_box, uint32_t color);
-void sim_grid_render(struct OffscreenBuffer *buffer, struct QuadTreeNode *node, uint32_t color);
+void sim_bounding_box_render(struct OffscreenBuffer *buffer, struct SimBounds *bounding_box, uint32_t color, float dx, float dy);
+void sim_grid_render(struct OffscreenBuffer *buffer, struct QuadTreeNode *node, uint32_t color, float dx, float dy);
void sim_cleanup(struct SimState *sim_state);
#define STAR_GARDEN_H
