Changeset 60578ce in opengl-game for scene-notes.txt

Timestamp:

Dec 18, 2019, 2:48:28 AM (5 years ago)

Author:

Dmitry Portnoy <dmp1488@…>

Branches:

feature/imgui-sdl, master, points-test

Children:

a79be34

Parents:

7c929fc

Message:

In VulkanGame, make lighting work correctly in the ship shader with the model, view, and projection matrices all being applied

File:

• scene-notes.txt (modified) (1 diff)

scene-notes.txt

@@ -2 +2 @@
 In vulkan, it is upper left, so I set the projection matrix [1][1] cell to -1 to flip the y-axis and make it match opengl
 
-+z goes into the screen (in Vulkan)
+depth ranges ([-1, 1] in OpenGL, [0, 1] in Vulkan)
+
+Vulkan coordinates:
+X+ points toward right
+Y+ points toward down (but I flip it in vulkangame in the perspective matrix to point up)
+Z+ points toward inside the screen
+
+In opengl, all 3 coordinates range from -1 to 1
+
+For the perspective matrix, after the vertex shader finishes, the x, y, and z of the final point are automatically divided
+by the w. For testing the projection matrix in the console, I could do that manually as well.