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The camera slowly moves back when you rotate it. It works for our purposes though. Feel free to improve it!")]),t._v(" "),n("p",[t._v("We still need to plug this into our existing code to make it do anything. Add the controller to "),n("code",[t._v("State")]),t._v(" and create it in "),n("code",[t._v("new()")]),t._v(".")]),t._v(" "),n("div",{staticClass:"language-rust extra-class"},[n("pre",{pre:!0,attrs:{class:"language-rust"}},[n("code",[n("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("struct")]),t._v(" "),n("span",{pre:!0,attrs:{class:"token type-definition class-name"}},[t._v("State")]),t._v(" "),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("{")]),t._v("\n "),n("span",{pre:!0,attrs:{class:"token comment"}},[t._v("// ...")]),t._v("\n camera"),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(":")]),t._v(" "),n("span",{pre:!0,attrs:{class:"token class-name"}},[t._v("Camera")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v("\n "),n("span",{pre:!0,attrs:{class:"token comment"}},[t._v("// NEW!")]),t._v("\n camera_controller"),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(":")]),t._v(" "),n("span",{pre:!0,attrs:{class:"token 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The values in our uniform buffer need to be updated. There are a few main methods to do that.")]),t._v(" "),n("ol",[n("li",[t._v("We can create a separate buffer and copy it's contents to our "),n("code",[t._v("uniform_buffer")]),t._v(". The new buffer is known as a staging buffer. This method is usually how it's done as it allows the contents of the main buffer (in this case "),n("code",[t._v("uniform_buffer")]),t._v(") to only be accessible by the gpu. The gpu can do some speed optimizations which it couldn't if we could access the buffer via the cpu.")]),t._v(" "),n("li",[t._v("We can call on of the mapping method's "),n("code",[t._v("map_read_async")]),t._v(", and "),n("code",[t._v("map_write_async")]),t._v(" on the buffer itself. These allow us to access a buffer's contents directly, but requires us to deal with the "),n("code",[t._v("async")]),t._v(" aspect of these methods this also requires our buffer to use the "),n("code",[t._v("BufferUsage::MAP_READ")]),t._v(" and/or "),n("code",[t._v("BufferUsage::MAP_WRITE")]),t._v(". We won't talk about it here, but you check out "),n("a",{attrs:{href:"../../showcase/windowless"}},[t._v("Wgpu without a window")]),t._v(" tutorial if you want to know more.")]),t._v(" "),n("li",[t._v("We can use "),n("code",[t._v("write_buffer")]),t._v(" on "),n("code",[t._v("queue")]),t._v(".")])]),t._v(" "),n("p",[t._v("We're going to use option number 3.")]),t._v(" "),n("div",{staticClass:"language-rust extra-class"},[n("pre",{pre:!0,attrs:{class:"language-rust"}},[n("code",[n("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("fn")]),t._v(" "),n("span",{pre:!0,attrs:{class:"token function-definition function"}},[t._v("update")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),n("span",{pre:!0,attrs:{class:"token operator"}},[t._v("&")]),n("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("mut")]),t._v(" "),n("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("self")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),t._v(" "),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("{")]),t._v("\n "),n("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("self")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),t._v("camera_controller"),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),n("span",{pre:!0,attrs:{class:"token function"}},[t._v("update_camera")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),n("span",{pre:!0,attrs:{class:"token operator"}},[t._v("&")]),n("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("mut")]),t._v(" "),n("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("self")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),t._v("camera"),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(";")]),t._v("\n "),n("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("self")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),t._v("uniforms"),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),n("span",{pre:!0,attrs:{class:"token function"}},[t._v("update_view_proj")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),n("span",{pre:!0,attrs:{class:"token operator"}},[t._v("&")]),n("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("self")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),t._v("camera"),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(";")]),t._v("\n "),n("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("self")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),t._v("queue"),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),n("span",{pre:!0,attrs:{class:"token function"}},[t._v("write_buffer")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),n("span",{pre:!0,attrs:{class:"token operator"}},[t._v("&")]),n("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("self")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),t._v("uniform_buffer"),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v(" "),n("span",{pre:!0,attrs:{class:"token number"}},[t._v("0")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v(" "),n("span",{pre:!0,attrs:{class:"token namespace"}},[t._v("bytemuck"),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("::")])]),n("span",{pre:!0,attrs:{class:"token function"}},[t._v("cast_slice")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),n("span",{pre:!0,attrs:{class:"token operator"}},[t._v("&")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("[")]),n("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("self")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(".")]),t._v("uniforms"),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("]")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(";")]),t._v("\n"),n("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("}")]),t._v("\n")])])]),n("p",[t._v("That's all we need to do. If you run the code now you should see a pentagon with our tree texture that you can rotate around and zoom into with the wasd/arrow keys.")]),t._v(" "),n("h2",{attrs:{id:"challenge"}},[n("a",{staticClass:"header-anchor",attrs:{href:"#challenge"}},[t._v("#")]),t._v(" Challenge")]),t._v(" "),n("p",[t._v("Have our model rotate on it's own independently of the the camera. 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- + diff --git a/beginner/tutorial3-pipeline/index.html b/beginner/tutorial3-pipeline/index.html index 385e94e0..c2e05846 100644 --- a/beginner/tutorial3-pipeline/index.html +++ b/beginner/tutorial3-pipeline/index.html @@ -8,7 +8,7 @@ - + @@ -255,6 +255,6 @@ →

- + diff --git a/beginner/tutorial4-buffer/index.html b/beginner/tutorial4-buffer/index.html index e5aa2430..fd9c89b3 100644 --- a/beginner/tutorial4-buffer/index.html +++ b/beginner/tutorial4-buffer/index.html @@ -8,7 +8,7 @@ - + @@ -252,6 +252,6 @@ render_pass. →

- + diff --git a/beginner/tutorial5-textures/index.html b/beginner/tutorial5-textures/index.html index 4399c50c..e905cf8d 100644 --- a/beginner/tutorial5-textures/index.html +++ b/beginner/tutorial5-textures/index.html @@ -8,7 +8,7 @@ - + @@ -399,6 +399,6 @@ render_pass. →

- + diff --git a/beginner/tutorial6-uniforms/index.html b/beginner/tutorial6-uniforms/index.html index 0134b661..2ce2b776 100644 --- a/beginner/tutorial6-uniforms/index.html +++ b/beginner/tutorial6-uniforms/index.html @@ -7,8 +7,8 @@ - - + + @@ -178,7 +178,7 @@ render_pass. }; void main() { - v_tex_coords = a_tex_coords; // UPDATED! + v_tex_coords = a_tex_coords; gl_Position = u_view_proj * vec4(a_position, 1.0); // 3. }
  1. Because we've created a new bind group, we need to specify which one we're using in the shader. The number is determined by our render_pipeline_layout. The texture_bind_group_layout is listed first, thus it's set=0, and uniform_bind_group is second, so it's set=1.
  2. The uniform block requires us to specify global identifiers for all the fields we intend to use. It's important to only specify fields that are actually in our uniform buffer, as trying to access data that isn't there may lead to undefined behavior.
  3. Multiplication order is important when it comes to matrices. The vector always goes on the right, and the matrices gone on the left in order of importance.

# A controller for our camera

If you run the code right now, you should get something that looks like this.

./static-tree.png

The shape's less stretched now, but it's still pretty static. You can experiment with moving the camera position around, but most cameras in games move around. Since this tutorial is about using wgpu and not how to process user input, I'm just going to post the CameraController code below.

struct CameraController {
@@ -278,7 +278,6 @@ render_pass.
             camera.eye = camera.target - (forward - right * self.speed).normalize() * forward_mag;
         }
     }
-    }
 }

This code is not perfect. The camera slowly moves back when you rotate it. It works for our purposes though. Feel free to improve it!

We still need to plug this into our existing code to make it do anything. Add the controller to State and create it in new().

struct State {
     // ...
@@ -309,7 +308,7 @@ render_pass.
     self.uniforms.update_view_proj(&self.camera);
     self.queue.write_buffer(&self.uniform_buffer, 0, bytemuck::cast_slice(&[self.uniforms]));
 }
-

That's all we need to do. If you run the code now you should see a pentagon with our tree texture that you can rotate around and zoom into with the wasd/arrow keys.

# Challenge

Have our model rotate on it's own independently of the the camera. Hint: you'll need another matrix for this.

Check out the code!
Last Updated: 3/21/2021, 2:01:00 PM

+

That's all we need to do. If you run the code now you should see a pentagon with our tree texture that you can rotate around and zoom into with the wasd/arrow keys.

# Challenge

Have our model rotate on it's own independently of the the camera. Hint: you'll need another matrix for this.

Check out the code!
Last Updated: 3/21/2021, 10:26:16 PM

← →

- + diff --git a/beginner/tutorial7-instancing/index.html b/beginner/tutorial7-instancing/index.html index 6f731335..60217a94 100644 --- a/beginner/tutorial7-instancing/index.html +++ b/beginner/tutorial7-instancing/index.html @@ -8,7 +8,7 @@ - + @@ -170,6 +170,6 @@ render_pass. →

- + diff --git a/beginner/tutorial8-depth/index.html b/beginner/tutorial8-depth/index.html index 099d6045..7da98209 100644 --- a/beginner/tutorial8-depth/index.html +++ b/beginner/tutorial8-depth/index.html @@ -8,7 +8,7 @@ - + @@ -111,6 +111,6 @@ →

- + diff --git a/beginner/tutorial9-models/index.html b/beginner/tutorial9-models/index.html index 5cdda0d2..8c5f4df2 100644 --- a/beginner/tutorial9-models/index.html +++ b/beginner/tutorial9-models/index.html @@ -8,7 +8,7 @@ - + @@ -333,6 +333,6 @@ render_pass. →

- + diff --git a/index.html b/index.html index ebcee831..cf98751d 100644 --- a/index.html +++ b/index.html @@ -8,7 +8,7 @@ - + @@ -17,6 +17,6 @@ →

- + diff --git a/intermediate/tutorial10-lighting/index.html b/intermediate/tutorial10-lighting/index.html index f73395c5..76c171ff 100644 --- a/intermediate/tutorial10-lighting/index.html +++ b/intermediate/tutorial10-lighting/index.html @@ -8,7 +8,7 @@ - + @@ -474,6 +474,6 @@ v_normal = normal_matrix - + diff --git a/intermediate/tutorial11-normals/index.html b/intermediate/tutorial11-normals/index.html index 3ea785e5..942010ad 100644 --- a/intermediate/tutorial11-normals/index.html +++ b/intermediate/tutorial11-normals/index.html @@ -8,7 +8,7 @@ - + @@ -479,6 +479,6 @@ render_pass. →

- + diff --git a/intermediate/tutorial12-camera/index.html b/intermediate/tutorial12-camera/index.html index ed33034b..891b5611 100644 --- a/intermediate/tutorial12-camera/index.html +++ b/intermediate/tutorial12-camera/index.html @@ -8,7 +8,7 @@ - + @@ -373,6 +373,6 @@ →

- + diff --git a/intermediate/tutorial13-threading/index.html b/intermediate/tutorial13-threading/index.html index addbbcbb..99210fbb 100644 --- a/intermediate/tutorial13-threading/index.html +++ b/intermediate/tutorial13-threading/index.html @@ -8,7 +8,7 @@ - + @@ -133,6 +133,6 @@ Elapsed (Threaded): 199.645027ms →

- + diff --git a/news/index.html b/news/index.html index 99fcd21c..266682bc 100644 --- a/news/index.html +++ b/news/index.html @@ -8,7 +8,7 @@ - + @@ -24,6 +24,6 @@

- + diff --git a/showcase/alignment/index.html b/showcase/alignment/index.html index e2b06b15..c9c14b39 100644 --- a/showcase/alignment/index.html +++ b/showcase/alignment/index.html @@ -8,7 +8,7 @@ - + @@ -23,6 +23,6 @@ →

- + diff --git a/showcase/compute/index.html b/showcase/compute/index.html index 658d2d1c..7d67aa61 100644 --- a/showcase/compute/index.html +++ b/showcase/compute/index.html @@ -8,7 +8,7 @@ - + @@ -122,6 +122,6 @@ →

- + diff --git a/showcase/gifs/index.html b/showcase/gifs/index.html index 089babc7..3b3646d5 100644 --- a/showcase/gifs/index.html +++ b/showcase/gifs/index.html @@ -8,7 +8,7 @@ - + @@ -149,6 +149,6 @@ →

- + diff --git a/showcase/imgui-demo/index.html b/showcase/imgui-demo/index.html index f7bd6e56..14a37655 100644 --- a/showcase/imgui-demo/index.html +++ b/showcase/imgui-demo/index.html @@ -8,7 +8,7 @@ - + @@ -114,6 +114,6 @@ display.queue - + diff --git a/showcase/index.html b/showcase/index.html index b5c3fc2f..1800e0a9 100644 --- a/showcase/index.html +++ b/showcase/index.html @@ -8,7 +8,7 @@ - + @@ -21,6 +21,6 @@ →

- + diff --git a/showcase/pong/index.html b/showcase/pong/index.html index bc6724a1..121d81f6 100644 --- a/showcase/pong/index.html +++ b/showcase/pong/index.html @@ -8,7 +8,7 @@ - + @@ -205,6 +205,6 @@ →

- + diff --git a/showcase/windowless/index.html b/showcase/windowless/index.html index 1c444891..bd0a3cfb 100644 --- a/showcase/windowless/index.html +++ b/showcase/windowless/index.html @@ -8,7 +8,7 @@ - + @@ -229,6 +229,6 @@ output_buffer. - + diff --git a/todo.html b/todo.html index cd40381e..425113b9 100644 --- a/todo.html +++ b/todo.html @@ -8,11 +8,11 @@ - + - +