add platforms and AABB collision

8 files changed, 161 insertions, 28 deletions

diff --git a/src/aabb.odin b/src/aabb.odin
new file mode 100644
index 0000000..9637ec9
--- /dev/null
+++ b/src/aabb.odin
@@ -0,0 +1,13 @@
+package demonchime
+
+aabb_hori :: proc(a: Rect, b: Rect) -> bool {
+  return a.start.x < b.start.x + b.size.x && b.start.x < a.start.x + a.size.x
+}
+
+aabb_vert :: proc(a: Rect, b: Rect) -> bool {
+  return a.start.y < b.start.y + b.size.y && b.start.y < a.start.y + a.size.y
+}
+
+aabb :: proc(a: Rect, b: Rect) -> bool {
+  return aabb_hori(a, b) && aabb_vert(a, b)
+}
diff --git a/src/constants.odin b/src/constants.odin
index ae763d7..d415c3e 100644
--- a/src/constants.odin
+++ b/src/constants.odin
@@ -1,4 +1,4 @@
 package demonchime
 
-GRAVITY :: 500
-TERMINAL_VELOCITY :: 500
+GRAVITY :: 1000
+TERMINAL_VELOCITY :: 900
diff --git a/src/draw/draw.odin b/src/draw/draw.odin
index d67e16c..1762b25 100644
--- a/src/draw/draw.odin
+++ b/src/draw/draw.odin
@@ -1,6 +1,5 @@
 package draw
 
-import "core:fmt"
 import "core:math/linalg"
 import "core:math"
 
@@ -20,8 +19,8 @@ Mat4 :: matrix[4, 4]f32
 
 Color :: [4]f32
 
-SCREEN_WIDTH :: 256
-SCREEN_HEIGHT :: 256
+SCREEN_WIDTH :: 480
+SCREEN_HEIGHT :: 360
 
 Renderer :: struct {
   screen: Framebuffer,
@@ -34,6 +33,8 @@ Renderer :: struct {
   view: sg.View,
   sampler: sg.Sampler,
 
+  white_1x1: sg.Image,
+
   projection: Mat4,
   current_batch: Batch,
 
@@ -69,6 +70,18 @@ init :: proc(r: ^Renderer) {
     },
   }
 
+  white := [?]u8{255, 255, 255, 255}
+
+  r.white_1x1 = sg.make_image({
+    width = 1,
+    height = 1,
+    data = {
+      mip_levels = {
+        0 = {ptr=&white, size=size_of(white)},
+      },
+    },
+  })
+
   init_framebuffer(
     &r.screen,
     SCREEN_WIDTH, SCREEN_HEIGHT,
@@ -125,7 +138,7 @@ end_frame :: proc(r: ^Renderer) {
     (f32(sapp.height()) - (SCREEN_HEIGHT * scale)) / 2,
   }
 
-  draw_texture(
+  texture(
     r,
     r.screen.img,
     screen_start,
@@ -210,12 +223,37 @@ batch_vertices :: proc(
   append(&b.vertices, ..vertices)
 }
 
-draw_texture :: proc{
-  draw_texture_full,
-  draw_texture_quad,
+rect :: proc(
+  r: ^Renderer,
+  rect: Rect,
+  color := Color{1, 1, 1, 1},
+) {
+  assert(rect.size.x > 0 && rect.size.y > 0)
+
+  batch := request_batch(r, r.white_1x1)
+
+  start := rect.start
+  end := rect.start + rect.size
+  
+  vertices := [?]Vertex{
+    {start,            {0, 0}, r.tint},
+    {{end.x, start.y}, {1, 0}, r.tint},
+    {{start.x, end.y}, {0, 1}, r.tint},
+
+    {{end.x, start.y}, {1, 0}, r.tint},
+    {{start.x, end.y}, {0, 1}, r.tint},
+    {end,              {1, 1}, r.tint},
+  }
+
+  batch_vertices(batch, vertices[:])
+}
+
+texture :: proc{
+  texture_full,
+  texture_quad,
 }
 
-draw_texture_quad :: proc(
+texture_quad :: proc(
   r: ^Renderer,
   img: sg.Image, 
   quad: Rect,
@@ -252,7 +290,7 @@ draw_texture_quad :: proc(
   batch_vertices(batch, vertices[:])
 }
 
-draw_texture_full :: proc(
+texture_full :: proc(
   r: ^Renderer,
   img: sg.Image, 
   pos: Vec2,
@@ -263,7 +301,5 @@ draw_texture_full :: proc(
     f32(sg.query_image_width(img)),
     f32(sg.query_image_height(img)),
   }
-  draw_texture_quad(r, img, Rect{Vec2{0, 0}, size}, pos, offset, scale)
+  texture_quad(r, img, Rect{Vec2{0, 0}, size}, pos, offset, scale)
 }
-
-
diff --git a/src/draw/sprite.odin b/src/draw/sprite.odin
index ff8ce58..59d1c32 100644
--- a/src/draw/sprite.odin
+++ b/src/draw/sprite.odin
@@ -1,12 +1,10 @@
 package draw
 
 import "core:log"
-import "core:math"
 import "core:image"
 import "core:image/qoi"
 
 import sg "shared:sokol/gfx"
-import stime "shared:sokol/time"
 
 Sprite :: struct {
   image: sg.Image,
@@ -85,13 +83,13 @@ update_sprite :: proc(sprite: ^Sprite, dt: f32) {
   }
 }
 
-draw_sprite :: proc(
+sprite :: proc(
   r: ^Renderer,
   sprite: Sprite,
 ) {
   frame := sprite.anim.frames[sprite.current_frame]
   
-  draw_texture(
+  texture(
     r,
     sprite.image,
     Rect {
diff --git a/src/entity_list.odin b/src/entity_list.odin
index 4890d2c..1f07ef9 100644
--- a/src/entity_list.odin
+++ b/src/entity_list.odin
@@ -1,6 +1,6 @@
 package demonchime
 
-// import "core:math"
+import "core:math"
 
 Entity_Handle :: struct {
   idx: u32,
diff --git a/src/main.odin b/src/main.odin
index 95ddbcd..9a9c91c 100644
--- a/src/main.odin
+++ b/src/main.odin
@@ -18,9 +18,16 @@ import "draw"
 
 Vec2 :: [2]f32
 
+Rect :: struct {
+  start: Vec2,
+  size: Vec2,
+}
+
 state: struct {
   player: Player,
 
+  platform_list: Entity_List(Platform),
+
   renderer: draw.Renderer,
 
   input: Input,
@@ -49,6 +56,26 @@ init :: proc "c" () {
   draw.init(&state.renderer)
 
   init_player(&state.player)
+
+  make_platform(Rect{
+    start = {50, 50},
+    size = {100, 20}
+  })
+
+  make_platform(Rect{
+    start = {20, 340},
+    size = {440, 20}
+  })
+
+  make_platform(Rect{
+    start = {140, 320},
+    size = {20, 20}
+  })
+
+  make_platform(Rect{
+    start = {240, 280},
+    size = {20, 20}
+  })
 }
 
 frame :: proc "c" () {
@@ -60,6 +87,8 @@ frame :: proc "c" () {
 
   draw_player(state.player)
 
+  draw_platforms()
+
   draw.end_frame(&state.renderer)
 
   free_all(context.temp_allocator)
@@ -78,6 +107,8 @@ event :: proc "c" (event: ^sapp.Event) {
 cleanup :: proc "c" () {
   context = default_context()
   sg.shutdown()
+
+  delete_entity_list(state.platform_list)
 }
 
 main :: proc() {
diff --git a/src/platform.odin b/src/platform.odin
new file mode 100644
index 0000000..b837355
--- /dev/null
+++ b/src/platform.odin
@@ -0,0 +1,21 @@
+package demonchime
+
+import "draw"
+
+Platform :: struct {
+  handle: Entity_Handle,
+  rect: Rect,
+}
+
+make_platform :: proc(rect: Rect) -> (Entity_Handle, ^Platform) {
+  return make_entity(&state.platform_list, Platform {
+    rect = rect,
+  })
+}
+
+draw_platforms :: proc() {
+  iter := iter_entity_list(state.platform_list)
+  for p in entity_list_iter(&iter) {
+    draw.rect(&state.renderer, cast(draw.Rect)p.rect)
+  }
+}
diff --git a/src/player.odin b/src/player.odin
index e098167..1dd79ae 100644
--- a/src/player.odin
+++ b/src/player.odin
@@ -2,7 +2,6 @@ package demonchime
 
 import "core:fmt"
 import "core:math"
-import "core:math/linalg"
 
 import sapp "shared:sokol/app"
 
@@ -13,11 +12,12 @@ Player :: struct {
   vel: Vec2,
   anim: draw.Animation,
   sprite: draw.Sprite,
+  on_floor: bool
 }
 
 PLAYER_SPEED :: 100
 PLAYER_ACCEL :: 10
-PLAYER_JUMP_FORCE :: 300
+PLAYER_JUMP_FORCE :: 350
 
 init_player :: proc(p: ^Player) {
   p.pos = Vec2{50, 50}
@@ -58,7 +58,7 @@ update_player :: proc(p: ^Player, dt: f32) {
     draw.set_sprite_active_tag(&p.sprite, "down_idle")
   }
 
-  if is_keybind_down(state.input, state.input.jump) && p.pos.y >= 256 {
+  if is_keybind_down(state.input, state.input.jump) && p.on_floor {
     p.vel.y = -PLAYER_JUMP_FORCE
   }
 
@@ -69,18 +69,52 @@ update_player :: proc(p: ^Player, dt: f32) {
   )
   p.vel.y = math.min(p.vel.y + GRAVITY * dt, TERMINAL_VELOCITY)
 
-  p.pos += p.vel * dt
-  
-  if p.pos.y > 256 {
-    p.pos.y = 256
-    p.vel.y = 0
+  res_pos := p.pos + p.vel * dt
+
+  rect_size := Vec2{f32(p.sprite.width), f32(p.sprite.height)}
+  rect_offset := Vec2{-rect_size.x / 2, -rect_size.y}
+
+  rect := Rect{
+    res_pos + rect_offset,
+    rect_size,
   }
 
+  p.on_floor = false
+
+  iter := iter_entity_list(state.platform_list)
+  for plat in entity_list_iter(&iter) {
+    if aabb(rect, plat.rect) {
+      prev_rect := Rect{
+        p.pos + rect_offset,
+        rect_size,
+      }
+      if aabb_hori(prev_rect, plat.rect) {
+        if p.vel.y > 0 {
+          res_pos.y = plat.rect.start.y - rect.size.y - rect_offset.y
+          p.on_floor = true
+        } else {
+          res_pos.y = plat.rect.start.y + plat.rect.size.y - rect_offset.y
+        }
+        p.vel.y = 0
+      } else if aabb_vert(prev_rect, plat.rect) {
+        if p.vel.x > 0 {
+          res_pos.x = plat.rect.start.x - rect.size.x - rect_offset.x
+        } else {
+          res_pos.x = plat.rect.start.x + plat.rect.size.x - rect_offset.x
+        }
+        p.vel.x = 0
+      }
+    }
+  }
+
+  p.pos = res_pos
+
   p.sprite.pos = p.pos
 
   draw.update_sprite(&p.sprite, dt)
 }
 
 draw_player :: proc(p: Player) {
-  draw.draw_sprite(&state.renderer, p.sprite)
+  draw.sprite(&state.renderer, p.sprite)
 }
+