fix matrix stuff (finally)

u07/matrixMath.c

@@ -89,6 +89,11 @@ void rotationZ(mat4* out, GLfloat angle) {
 }
 
 // CREATE 4x4 ROTATION MATRIX AROUND Y AXIS
+/*  cos a     0   sin a    0
+ *    0       1     0      0
+ * -sin a     0   cos a    0
+ *    0       0     0      1
+*/
 void rotationY(mat4* out, GLfloat angle) {
 	identity(out);
 	out->m00 = cos(angle);
@@ -209,7 +214,16 @@ void mat3From4(mat3* out, mat4* in) {
 	memcpy(&out->m02, &in->m02, sizeof(vec3));
 }
 
-void mat3Adjoint(mat3* out, mat3* in) {
+void mat3Transpose(mat3* out, mat3* in) {
+	transposeAny((GLfloat*)out, (GLfloat*)in, 3, 3);
+}
+
+/**
+ *  a - m00   b - m01   c - m02
+ *  d - m10   e - m11   f - m12
+ *  g - m20   h - m21   i - m22
+ */
+void mat3Minor(mat3* out, mat3* in) {
 	mat3 result;
 
 	result.m00 = in->m11 * in->m22 - in->m21 * in->m12;
@@ -227,6 +241,21 @@ void mat3Adjoint(mat3* out, mat3* in) {
 	memcpy(out, &result, sizeof(mat3));
 }
 
+void mat3Cofactor(mat3* out, mat3* in) {
+	mat3 result;
+	mat3Minor(out, in);
+
+	out->m01 *= -1;
+	out->m10 *= -1;
+	out->m21 *= -1;
+	out->m12 *= -1;
+}
+
+void mat3Adjoint(mat3* out, mat3* in) {
+	mat3Cofactor(out, in);
+	mat3Transpose(out, out);
+}
+
 void mat3MultiplyScalar(mat3* out, mat3* in, GLfloat x) {
 	for (int i = 0; i < 9; i++) {
 		((GLfloat*)out)[i] = ((GLfloat*)in)[i] * x;
@@ -245,10 +274,6 @@ GLfloat mat3Determinant(mat3* M) {
 	;
 }
 
-void mat3Transpose(mat3* out, mat3* in) {
-	transposeAny((GLfloat*)out, (GLfloat*)in, 3, 3);
-}
-
 void mat3Inverse(mat3* out, mat3* in) {
 	mat3 result;
 	mat3Adjoint(&result, in);
@@ -260,7 +285,7 @@ void mat3Inverse(mat3* out, mat3* in) {
 GLfloat sumDiffAny(GLfloat* A, GLfloat* B, int w, int h) {
 	GLfloat result = 0;
 	for (int i = 0; i < w * h; i++) {
-		result += abs(A[i] - B[i]);
+		result += fabs(A[i] - B[i]);
 	}
 	return result;
 }

u07/matrixMath.h

@@ -86,10 +86,12 @@ extern void mat4Print(mat4* m);
 extern void mat3Print(mat3* m);
 
 extern void mat3From4(mat3* out, mat4* in);
-extern void mat3Adjoint(mat3* out, mat3* in);
 extern void mat3MultiplyScalar(mat3* out, mat3* in, GLfloat x);
 extern GLfloat mat3Determinant(mat3* m);
 extern void mat3Transpose(mat3* out, mat3* in);
+extern void mat3Minor(mat3* out, mat3* in);
+extern void mat3Cofactor(mat3* out, mat3* in);
+extern void mat3Adjoint(mat3* out, mat3* in);
 extern void mat3Inverse(mat3* out, mat3* in);
 
 extern GLfloat sumDiffAny(GLfloat* A, GLfloat* B, int w, int h); 

u07/test.c

@@ -5,22 +5,28 @@
 
 #include "matrixMath.h"
 
+
+#define KRED  "\x1B[31m"
+#define KGRN  "\x1B[32m"
+#define KNRM  "\x1B[0m"
+
 #define EPSILON 0.001f
 
+int exitCode = 0;
+
 void printTest(char* name, bool result) {
 	if (result) {
-		printf("    PASSED - ");
+		printf("%s    PASSED%s - %s\n", KGRN, KNRM, name);
 	} else {
-		printf("!!! FAILED - ");
+		printf("%s!!! FAILED%s - %s\n", KRED, KNRM, name);
+		exitCode = 1;
 	}
-	printf("%s", name);
-	printf("\n");
 }
 
 void testSumDiff() {
-	mat3 A = {1.0f, 0.0f, 0.0f, -1.0f, 0.0f, -1.0f, 1.0f, -1.0f, 9.0f};
+	mat3 A = {1, 0, 0, -1, 0, -1, 1, -1, 9};
-	mat3 B = {0.0f, 1.0f, -1.0f, 0.0f, 0.0f, 1.0f, 1.0f, -1.0f, 8.0f};
+	mat3 B = {0, 1, -1, 0, 0, 1, 1, -1, 8};
-	GLfloat target = 7.0f;
+	GLfloat target = 7;
 
 	GLfloat value = mat3SumDiff(&A, &B);
 
@@ -38,9 +44,28 @@ void testSumDiff() {
 	printTest("mat3SumDiff", result);
 }
 
+void testMat3Minor() {
+	mat3 M = {2, 0, 1, -1, 5, -1, 3, 2, -2};
+	mat3 target = {-8, 5, -17, -2, -7, 4, -5, -1, 10};
+
+	mat3Minor(&M, &M);
+
+	printTest("mat3Minor", mat3SumDiff(&M, &target) < EPSILON);
+}
+
+void testMat3Cofactor() {
+	mat3 M = {2, 0, 1, -1, 5, -1, 3, 2, -2};
+	mat3 target = {-8, -5, -17, 2, -7, -4, -5, 1, 10};
+
+	mat3Cofactor(&M, &M);
+
+	printTest("mat3Cofactor", mat3SumDiff(&M, &target) < EPSILON);
+}
+
 void testMat3Adjoint() {
-	mat3 M = {2.0f, 0.0f, 1.0f, -1.0f, 5.0f, -1.0f, 3.0f, 2.0f, -2.0f};
+	mat3 M = {1, 2, -1, 2, 1, 2, -1, 2, 1};
-	mat3 target = {-8.0f, 5.0f, -17.0f, -2.0f, -7.0f, 4.0f, -5.0f, -1.0f, 10.0f};
+	mat3 target = {-3, -4, 5, -4, 0, -4, 5, -4, -3};
+
 
 	mat3Adjoint(&M, &M);
 
@@ -48,9 +73,9 @@ void testMat3Adjoint() {
 }
 
 void testMat3MultiplyScalar() {
-	mat3 M = {1.0f, 2.0f, 3.0f, 4.0f, 0.0f, -1.5f, -2.5f, -3.5f, -4.5f};
+	mat3 M = {1, 2, 3, 4, 0, -1.5f, -2.5f, -3.5f, -4.5f};
 	GLfloat x = 0.9f;
-	mat3 target = {0.9f, 1.8f, 2.7f, 3.6f, 0.0f, -1.35f, -2.25f, -3.15f, -4.05f};
+	mat3 target = {0.9f, 1.8f, 2.7f, 3.6f, 0, -1.35f, -2.25f, -3.15f, -4.05f};
 
 	mat3MultiplyScalar(&M, &M, x);
 
@@ -58,25 +83,48 @@ void testMat3MultiplyScalar() {
 }
 
 void testMat3Determinant() {
-	mat3 M = {1.0f, -3.0f, 2.0f, 3.0f, -1.0f, 3.0f, 2.0f, -3.0f, 1.0f};
+	mat3 M = {1, -3, 2, 3, -1, 3, 2, -3, 1};
-	GLfloat target = -15.0f;
+	GLfloat target = -15;
 
 	printTest("mat3Determinant", fabs(mat3Determinant(&M) - target) < EPSILON);
 }
 
 void testMat3Inverse() {
-	mat3 M = {1.0f, 2.0f, -1.0f, 2.0f, 1.0f, 2.0f, -1.0f, 2.0f, 1.0f};
+	mat3 M = {1, 2, -1, 2, 1, 2, -1, 2, 1};
-	mat3 target = {0.1875f, 0.25f, -0.3125f, 0.2f, 0.0f, 0.25f, -0.3125f, 0.25f, 0.1875f};
+	mat3 target = {0.1875f, 0.25f, -0.3125f, 0.25f, 0, 0.25f, -0.3125f, 0.25f, 0.1875f};
 
 	mat3Inverse(&M, &M);
 
-	printTest("mat3Inverse", mat3SumDiff(&M, &target) < EPSILON);
+	bool result = mat3SumDiff(&M, &target) < EPSILON;
+
+	if (!result) {
+		printf("\nM:\n");
+		mat3Print(&M);
+		printf("\ntarget:\n");
+		mat3Print(&target);
+	}
+
+	printTest("mat3Inverse", result);
+}
+
+void testMat3Transpose() {
+	mat3 M = {1, 2, 3, 4, 5, 6, 7, 8, 9};
+	mat3 target = {1, 4, 7, 2, 5, 8, 3, 6, 9};
+
+	mat3Transpose(&M, &M);
+
+	printTest("mat3Transpose", mat3SumDiff(&M, &target) < EPSILON);
 }
 
 int main(void) {
 	testSumDiff();
+	testMat3Minor();
+	testMat3Cofactor();
 	testMat3Adjoint();
 	testMat3MultiplyScalar();
 	testMat3Determinant();
 	testMat3Inverse();
+	testMat3Transpose();
+
+	return exitCode;
 }

u07/vertexShader.glsl

@@ -12,6 +12,9 @@ out vec3 fragmentPosition;
 void main() {
 	normal = normalModelView * aNormal;
 
-	gl_Position = projection * modelView * vec4(aPosition, 1.0);
+	vec4 modelViewPos = modelView * vec4(aPosition, 1.0);
-	fragmentPosition = vec3(modelView * vec4(aPosition, 1.0));
+
+	gl_Position = projection * modelViewPos;
+	
+	fragmentPosition = vec3(modelViewPos);
 }