add basic lighting

source/main.cpp

@@ -59,9 +59,10 @@ static DVLB_s* vshaderDVLB;
 static shaderProgram_s program;
 static s8 spheresUniformLocation;
 static s8 sphereColorsUniformLocation;
-static s8 randLocation;
+static s8 sphereLightsUniformLocation;
+static s8 randUniformLocation;
 
-static constexpr unsigned int VERTEX_COUNT_W = 150;
+static constexpr unsigned int VERTEX_COUNT_W = 210;
 static constexpr unsigned int VERTEX_COUNT_H = 10 * VERTEX_COUNT_W / 6;
 static constexpr unsigned int VERTEX_COUNT = VERTEX_COUNT_W * VERTEX_COUNT_H;
 
@@ -111,12 +112,12 @@ static void setupVertices()
 		{
 			vertex& v = vertexList[x + y * VERTEX_COUNT_W];
 
-			const float s = static_cast<float>(x + rand01()) / VERTEX_COUNT_W;
+			const float s = static_cast<float>(x) / VERTEX_COUNT_W;
-			const float t = static_cast<float>(y + rand01()) / VERTEX_COUNT_H;
+			const float t = static_cast<float>(y) / VERTEX_COUNT_H;
 
 			// swapped due to 3DS screen orientation
-			v.st[0] = t;
+			v.st[0] = t + rand01() / VERTEX_COUNT_W;
-			v.st[1] = s;
+			v.st[1] = s + rand01() / VERTEX_COUNT_H;
 
 			v.coords[0] = 2.0f * s - 1.0f;
 			v.coords[1] = 2.0f * t - 1.0f;
@@ -128,9 +129,12 @@ static void setupVertices()
 	}
 
 	memcpy(vboData, vertexList, sizeof(vertexList));
+}
 
-	constexpr int NUM_RAND = 4;
+static void setupRandom()
-	C3D_FVec* randPtr = C3D_FVUnifWritePtr(GPU_VERTEX_SHADER, randLocation, NUM_RAND);
+{
+	constexpr int NUM_RAND = 10;
+	C3D_FVec* randPtr = C3D_FVUnifWritePtr(GPU_VERTEX_SHADER, randUniformLocation, NUM_RAND);
 	for (int i = 0; i < NUM_RAND; i++)
 	{
 		randPtr[i] = randvec();
@@ -162,7 +166,8 @@ static void sceneInit()
 
 	spheresUniformLocation = shaderInstanceGetUniformLocation(program.vertexShader, "spheres");
 	sphereColorsUniformLocation = shaderInstanceGetUniformLocation(program.vertexShader, "sphereColors");
-	randLocation = shaderInstanceGetUniformLocation(program.vertexShader, "rand");
+	sphereLightsUniformLocation = shaderInstanceGetUniformLocation(program.vertexShader, "sphereLights");
+	randUniformLocation = shaderInstanceGetUniformLocation(program.vertexShader, "rand");
 
 	C3D_AttrInfo* attrInfo = C3D_GetAttrInfo();
 	AttrInfo_Init(attrInfo);
@@ -187,16 +192,24 @@ static void sceneInit()
 	C3D_TexEnvFunc(env, C3D_RGB, GPU_INTERPOLATE);
 	C3D_TexEnvFunc(env, C3D_Alpha, GPU_REPLACE);
 
-	constexpr u16 NUM_SPHERES = 3;
+	constexpr u16 NUM_SPHERES = 4;
 	C3D_FVec* spheres = C3D_FVUnifWritePtr(GPU_VERTEX_SHADER, spheresUniformLocation, NUM_SPHERES);
 	spheres[0] = FVec4_New(0.0f, -100.5f, -1.0f, 100.0f);
 	spheres[1] = FVec4_New(0.6f, 0.0f, -1.0f, 0.5f);
 	spheres[2] = FVec4_New(-0.6f, 0.0f, -1.0f, 0.5f);
+	spheres[3] = FVec4_New(0.0f, 1.75f, -1.0f, 1.0f);
 
 	C3D_FVec* sphereColors = C3D_FVUnifWritePtr(GPU_VERTEX_SHADER, sphereColorsUniformLocation, NUM_SPHERES);
 	sphereColors[0] = FVec3_New(0.9f, 0.3f, 0.3f);
 	sphereColors[1] = FVec3_New(0.3f, 0.9f, 0.3f);
 	sphereColors[2] = FVec3_New(0.3f, 0.3f, 0.9f);
+	sphereColors[3] = FVec3_New(1.0f, 1.0f, 1.0f);
+
+	C3D_FVec* sphereLights = C3D_FVUnifWritePtr(GPU_VERTEX_SHADER, sphereLightsUniformLocation, NUM_SPHERES);
+	sphereLights[0] = FVec3_New(0.0f, 0.0f, 0.0f);
+	sphereLights[1] = FVec3_New(0.0f, 0.0f, 0.0f);
+	sphereLights[2] = FVec3_New(0.0f, 0.0f, 0.0f);
+	sphereLights[3] = FVec3_New(1.0f, 1.0f, 1.0f);
 }
 
 static void sceneRender()
@@ -323,6 +336,7 @@ int main(int argc, char* argv[])
 		}
 
 		setupVertices();
+		setupRandom();
 
 		C3D_TexEnvColor(C3D_GetTexEnv(0), getFrameNumColor(frameNum));
 

source/vshader.v.pica

@@ -7,21 +7,24 @@
 .alias far myconst.wwww
 .alias noHit myconst2.yyyy
 
-.consti bounceLoopParams(3, 0, 1, 0)
+.consti bounceLoopParams(9, 0, 1, 0)
-.consti calcSphereLoopParams(2, 0, 1, 0)
+.consti calcSphereLoopParams(3, 0, 1, 0)
 
 .setb b0 true
 .alias true b0
 
 ; xyz center (in world space)
 ; w radius (in world space)
-.fvec spheres[3]
+.fvec spheres[4]
 
 ; material albedo
-.fvec sphereColors[3]
+.fvec sphereColors[4]
+
+; material emitted light
+.fvec sphereLights[4]
 
 ; random numbers
-.fvec rand[4]
+.fvec rand[10]
 
 .in inOrigin v0
 .in inLowerLeftCorner v1
@@ -51,10 +54,12 @@
 	mad r2.xyz, inHorizontal, r3.x, r2.xyz
 	mad r2.xyz, inVertical, r3.y, r2.xyz
 
-	; set initial color to (1, 1, 1)
+	; set initial color multiplier to (1, 1, 1)
-	; as lights are not implemented yet
 	mov r4.xyz, ones
 
+	; set initial color to (0, 0, 0)
+	mov r13.xyz, zeros
+
 	; calculate light bounces
 	for bounceLoopParams
 		; setup random numbers for this iteration
@@ -156,20 +161,24 @@
 				; set albedo
 				mov r10.xyz, sphereColors[aL].xyz
 
+				; set light emitted
+				mov r12.xyz, sphereLights[aL].xyz
+
 				; early exit label
 				calcSphereExit:
 				nop
 			; done with calculation
 		.end
 
-		; check if noHit > albedo
+		; check if noHit < albedo
-		cmp noHit.xyz, le, le, r10.xyz
+		cmp noHit.xyz, lt, lt, r10.xyz
 		breakc cmp.x
-		jmpc cmp.x, noHitLabel
 
 		; multiply color by albedo
 		mul r4.xyz, r4.xyz, r10.xyz
 
+		mad r13.xyz, r4.xyz, r12.xyz, r13.xyz
+
 		; set r1 to new ray origin
 		mov r1.xyz, r5.xyz
 
@@ -177,10 +186,10 @@
 		add r2.xyz, r7.xyz, r11.xyz
 	.end
 
-	noHitLabel:
-
 	; copy final color to output
-	mov outColor.xyz, r4.xyz
+	; min r13.xyz, ones, r13.xyz
+	mov outColor.xyz, r13.xyz
+
 	; set alpha to 1
 	mov outColor.w, ones
 
@@ -197,12 +206,14 @@
 ;   r3.xyz:   sphere origin
 ;	r3.w:     sphere radius
 ;   r4.w:     min distance
-;   r11.xyzw: random numbers
+;   r11.xyz:  random unit vector
+;   r11.w:    random number
 ;
 ; Outputs
 ; -------
 ;   r4.w:     new min distance
 ;   r10.xyz:  albedo
+;   r12.xyz:  light emitted
 ;
 ; Temporaries
 ; -----------