Adjusting Sprite Cards to Counter Projection | Episode Guide

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0:02Recap and set the stage for the day

1:07handmade_math.h: Make PerspectiveProjection() set the near clip plane to a positive value and perform some test multiplications

3:58Step into PerspectiveProjection() and inspect Test0 and Test1

6:42Blackboard: Check our clip plane equations

12:29handmade_math.h: Swap the perspective and non-perspective code in PerspectiveProjection(), step into it and inspect Test0 and Test1 again

16:42Blackboard: Solving for d and e

22:04handmade_math.h: Make PerspectiveProjection() compute Test0 and Test1 using negated n and f, step into it and inspect them again

23:37handmade_math.h: Switch PerspectiveProjection() to use the perspective correct equation, step in and inspect the Test0 and Test1

24:42Blackboard: Checking the math for the perspective correct terms

33:32handmade_math.h: Simplify the d term for the perspective correct equation

34:43Blackboard: Solving for d and e in the perspective correct clip plane equations

38:51handmade_platform.h: Rename w to __ in the v3 union

40:48Step into PerspectiveProjection() and inspect Test0 and Test1

42:06Run the game to see that we're back in business

43:30handmade_render_group.cpp: Make PushBitmap() tilt upright sprites and run the game

44:40Reflect on our unwitting correctness

47:27Blackboard: Sprite Cards

51:24Run the game to demo the squatness of the trees

53:41Blackboard: Producing the sprites' depth and height using the camera's relative position

55:18"Watch this point"^α

59:14Blackboard: Approaching this problem using ray intersections

1:03:08Blackboard: Solving for ray intersects ray

1:09:02Blackboard: Simplifying this down

1:12:56Blackboard: Handling the case when the vectors are parallel

1:20:13Blackboard: Determining the conditions under which this equation is unsolvable

1:23:29handmade_math.h: Introduce RayIntersect2()

1:27:01Blackboard: Producing a ta that goes with the same denominator

1:39:43handmade_math.h: Make RayIntersect2() compute ta and tb using the same denominator

1:43:21Try to solve our equations using an online tool

1:48:07handmade_render_group.cpp: Make PushBitmap() compute and call RayIntersect2() on the camera and card positions

1:54:22handmade_render_group.h: Add CameraP, CameraX, CameraY and CameraZ to the render_group struct

1:57:56handmade_render_group.cpp: Make SetCameraTransform() take the Camera position values

2:01:17Run the game to see that it is not nearly as messed up as expected

2:02:07Q&A

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2:02:07Q&A

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2:02:07Q&A

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2:03:09quikligames There was a lot of chat about Wolfram expecting 1-letter variable names and interpreting rbx as r * b * x

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2:03:09quikligames There was a lot of chat about Wolfram expecting 1-letter variable names and interpreting rbx as r * b * x

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2:03:09quikligames There was a lot of chat about Wolfram expecting 1-letter variable names and interpreting rbx as r * b * x

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2:03:23billdstrong Didn't we do this math when doing the screen projection?

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2:03:23billdstrong Didn't we do this math when doing the screen projection?

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2:03:23billdstrong Didn't we do this math when doing the screen projection?

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2:04:12Miblo Do you think we needed an epilepsy warning there?

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2:04:12Miblo Do you think we needed an epilepsy warning there?

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2:04:12Miblo Do you think we needed an epilepsy warning there?

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2:04:44pepevel Hello, yesterday I was asking about shaders and the z-buffer. Could I rephrase the question? It will be the last time

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2:04:44pepevel Hello, yesterday I was asking about shaders and the z-buffer. Could I rephrase the question? It will be the last time

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2:04:44pepevel Hello, yesterday I was asking about shaders and the z-buffer. Could I rephrase the question? It will be the last time

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2:05:00macielda Maybe if you swap the order of the sum on 'tb = ...' you get an equation more similar to 'ta = ...'?

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2:05:00macielda Maybe if you swap the order of the sum on 'tb = ...' you get an equation more similar to 'ta = ...'?

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2:05:00macielda Maybe if you swap the order of the sum on 'tb = ...' you get an equation more similar to 'ta = ...'?

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2:05:26handmade_math.h: Try swapping the order of the sum in RayIntersect2()

2:06:03vaualbus Can you show again the equation?

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2:06:03vaualbus Can you show again the equation?

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2:06:03vaualbus Can you show again the equation?

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2:07:11zennmystic Is the stream weekends only now or is it temp thing?

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2:07:11zennmystic Is the stream weekends only now or is it temp thing?

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2:07:11zennmystic Is the stream weekends only now or is it temp thing?

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2:07:31insobot 1935 is Molly Rocket's upcoming volitional fiction game, set in the criminal underworld of New York City in the 1930s¹

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2:07:31insobot 1935 is Molly Rocket's upcoming volitional fiction game, set in the criminal underworld of New York City in the 1930s¹

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2:07:31insobot 1935 is Molly Rocket's upcoming volitional fiction game, set in the criminal underworld of New York City in the 1930s¹

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2:07:37pepevel As Handmade Hero is a 2D game, my idea would be to treat the z variable not as the z coordinate but as a variable that the pixel shader will use to kill hidden pixels and do alpha blending with the GPU power

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2:07:37pepevel As Handmade Hero is a 2D game, my idea would be to treat the z variable not as the z coordinate but as a variable that the pixel shader will use to kill hidden pixels and do alpha blending with the GPU power

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2:07:37pepevel As Handmade Hero is a 2D game, my idea would be to treat the z variable not as the z coordinate but as a variable that the pixel shader will use to kill hidden pixels and do alpha blending with the GPU power

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2:10:28macielda Are you doing this so you can mix perspective projection and orthographic projection for game objects?

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2:10:28macielda Are you doing this so you can mix perspective projection and orthographic projection for game objects?

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2:10:28macielda Are you doing this so you can mix perspective projection and orthographic projection for game objects?

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2:11:31rooctag Now we have the alpha issue with the 3D stuff, is this easier to fix than the 2D sort because you already know how to fix that?

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2:11:31rooctag Now we have the alpha issue with the 3D stuff, is this easier to fix than the 2D sort because you already know how to fix that?

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2:11:31rooctag Now we have the alpha issue with the 3D stuff, is this easier to fix than the 2D sort because you already know how to fix that?

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2:13:32vaualbus This could be the solutiun at least for Matlab: [ta = -(Pax*rby - Pay*rbx - Pbx*rby + Pby*rbx)/(rax*rby - ray*rbx), tb = -(Pax*ray - Pay*rax - Pbx*ray + Pby*rax)/(rax*rby - ray*rbx)]

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2:13:32vaualbus This could be the solutiun at least for Matlab: [ta = -(Pax*rby - Pay*rbx - Pbx*rby + Pby*rbx)/(rax*rby - ray*rbx), tb = -(Pax*ray - Pay*rax - Pbx*ray + Pby*rax)/(rax*rby - ray*rbx)]

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2:13:32vaualbus This could be the solutiun at least for Matlab: [ta = -(Pax*rby - Pay*rbx - Pbx*rby + Pby*rbx)/(rax*rby - ray*rbx), tb = -(Pax*ray - Pay*rax - Pbx*ray + Pby*rax)/(rax*rby - ray*rbx)]

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2:17:57handmade_render_group.cpp: Make PushBitmap() use CardRyz to set the YAxis

2:18:24Run the game to see that we're surprisingly good

2:20:01macielda It seems like vaualbus' solution is negated in relation to yours

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2:20:01macielda It seems like vaualbus' solution is negated in relation to yours

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2:20:01macielda It seems like vaualbus' solution is negated in relation to yours

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2:23:14handmade_render_group.cpp: Enable PushBitmap() to produce a standard sprite card and run the game to see that

2:25:14handmade_opengl.cpp: Temporarily make OpenGLRenderCommands() clip out all transparent pixels, and run the game

2:27:47Consider addressing transparency in the sort, and close it down

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2:27:47Consider addressing transparency in the sort, and close it down

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2:27:47Consider addressing transparency in the sort, and close it down

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