move sphere intersection test back to procedure, prepare for multiple material types

Makefile

@@ -40,13 +40,15 @@ GRAPHICS	:=	gfx
 GFXBUILD	:=	$(BUILD)
 #ROMFS		:=	romfs
 #GFXBUILD	:=	$(ROMFS)/gfx
+APP_TITLE   :=  rt
+APP_AUTHOR  :=  Shy
 
 #---------------------------------------------------------------------------------
 # options for code generation
 #---------------------------------------------------------------------------------
 ARCH	:=	-march=armv6k -mtune=mpcore -mfloat-abi=hard -mtp=soft
 
-CFLAGS	:=	-g -Wall -O2 -mword-relocations \
+CFLAGS	:=	-Wall -O3 -mword-relocations \
 			-ffunction-sections \
 			$(ARCH)
 

source/main.cpp

@@ -62,7 +62,7 @@ static s8 sphereColorsUniformLocation;
 static s8 sphereLightsUniformLocation;
 static s8 randUniformLocation;
 
-static constexpr unsigned int VERTEX_COUNT_W = 210;
+static constexpr unsigned int VERTEX_COUNT_W = 150;
 static constexpr unsigned int VERTEX_COUNT_H = 10 * VERTEX_COUNT_W / 6;
 static constexpr unsigned int VERTEX_COUNT = VERTEX_COUNT_W * VERTEX_COUNT_H;
 
@@ -197,7 +197,7 @@ static void sceneInit()
 	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);
+	spheres[3] = FVec4_New(0.0f, 10.0f, -1.0f, 9.0f);
 
 	C3D_FVec* sphereColors = C3D_FVUnifWritePtr(GPU_VERTEX_SHADER, sphereColorsUniformLocation, NUM_SPHERES);
 	sphereColors[0] = FVec3_New(0.9f, 0.3f, 0.3f);

source/vshader.v.pica

@@ -77,7 +77,68 @@
 			mov r3, spheres[aL]
 			
 			; do calculation
-			; call calcSphere
+			call calcSphere
+		.end
+
+		; check if noHit < albedo
+		; and exit early if true
+		; as albedo has not been set
+		; after the initial set
+		; which only happens when
+		; a ray does not hit any spheres
+		cmp noHit.xyz, lt, lt, r10.xyz
+		breakc cmp.x
+
+		; multiply color by albedo
+		mul r4.xyz, r4.xyz, r10.xyz
+
+		; add emitted light
+		mad r13.xyz, r4.xyz, r12.xyz, r13.xyz
+
+		; set r1 to new ray origin
+		mov r1.xyz, r5.xyz
+
+		; set r2 to new ray direction
+		call diffuse
+	.end
+
+	; copy final color to output
+	mov outColor.xyz, r13.xyz
+
+	; set alpha to 1
+	mov outColor.w, ones
+
+	end
+.end
+
+; Calculate Sphere Intersection
+; -----------------------------
+;
+; Inputs
+; ------
+;   r1.xyz:   ray origin
+;   r2.xyz:   ray direction
+;   r3.xyz:   sphere origin
+;	r3.w:     sphere radius
+;   r4.w:     min distance
+;   r11.xyz:  random unit vector
+;   r11.w:    random number
+;
+; Outputs
+; -------
+;   r4.w:     new min distance
+;   r10.xyz:  albedo
+;   r12.xyz:  light emitted
+;
+; Temporaries
+; -----------
+;   r5.xyz:   new origin
+;   r6.xyz:   new direction
+;   r7.xyz:   hit normal
+;   r8.xyzw:  used for calculations
+;   r9.xyzw:  used for calculations
+
+.proc calcSphere
 	; vec3 oc = origin - center
 	add r8.xyz, r1.xyz, -r3.xyz
 
@@ -167,58 +228,8 @@
 	; early exit label
 	calcSphereExit:
 	nop
-			; done with calculation
 .end
 
-		; check if noHit < albedo
+.proc diffuse
-		cmp noHit.xyz, lt, lt, r10.xyz
-		breakc cmp.x
-
-		; 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
-
-		; set r2 to new ray direction
 	add r2.xyz, r7.xyz, r11.xyz
 .end
-
-	; copy final color to output
-	; min r13.xyz, ones, r13.xyz
-	mov outColor.xyz, r13.xyz
-
-	; set alpha to 1
-	mov outColor.w, ones
-
-	end
-.end
-
-; Calculate Sphere Intersection
-; -----------------------------
-;
-; Inputs
-; ------
-;   r1.xyz:   ray origin
-;   r2.xyz:   ray direction
-;   r3.xyz:   sphere origin
-;	r3.w:     sphere radius
-;   r4.w:     min distance
-;   r11.xyz:  random unit vector
-;   r11.w:    random number
-;
-; Outputs
-; -------
-;   r4.w:     new min distance
-;   r10.xyz:  albedo
-;   r12.xyz:  light emitted
-;
-; Temporaries
-; -----------
-;   r5.xyz:   new origin
-;   r6.xyz:   new direction
-;   r7.xyz:   hit normal
-;   r8.xyzw:  used for calculations
-;   r9.xyzw:  used for calculations