nolibgs_hello_worlds/hello_light.c
2021-06-26 19:24:40 +02:00

276 lines
12 KiB
C

/* hello_light.c, by Schnappy, 06-2021
- Demonstrates setting and using light sources in 3D without libgs.
Controls:
Start - Toggle interactive/non-interactive mode.
Select - Reset object's position and angles.
L1/L2 - Move object closer/farther.
L2/R2 - Rotate object (XY).
Up/Down/Left/Right - Rotate object (XZ/YZ).
Triangle/Cross/Square/Circle - Move object up/down/left/right.
based on primdraw.c by Lameguy64 (http://www.psxdev.net/forum/viewtopic.php?f=64&t=537)
2014 Meido-Tek Productions.
*/
/* PSX screen coordinate system
*
* Z+
* /
* /
* +------X+
* /|
* / |
* / Y+
* eye */
#include <sys/types.h>
#include <libgte.h>
#include <libgpu.h>
#include <libetc.h>
#include <stdio.h>
// Sample vector model
#include "cube.c"
#define VMODE 0
#define SCREENXRES 320
#define SCREENYRES 240
#define CENTERX SCREENXRES/2
#define CENTERY SCREENYRES/2
#define OTLEN 2048 // Maximum number of OT entries
#define PRIMBUFFLEN 32768 // Maximum number of POLY_GT3 primitives
// Display and draw environments, double buffered
DISPENV disp[2];
DRAWENV draw[2];
u_long ot[2][OTLEN]; // Ordering table (contains addresses to primitives)
char primbuff[2][PRIMBUFFLEN] = {0}; // Primitive list // That's our prim buffer
char * nextpri = primbuff[0]; // Primitive counter
short db = 0; // Current buffer counter
long t, p, OTz, Flag; // t == vertex count, p == depth cueing interpolation value, OTz == value to create Z-ordered OT, Flag == see LibOver47.pdf, p.143
// Lighting
// See PsyQ's LibOver47.pdf, p.133 for more details on the purpose of each component and full calculations.
// Far color : This is the color used to fade to when the mesh is far from the cam (NearFog)
CVECTOR BGc = {150, 50, 75, 0};
// Back color
VECTOR BKc = {128, 128, 128, 0};
// Light rotation angle
SVECTOR lgtang = {0, 0, 0};
// These will be used to store the light rotation matrix, cube rotation matrix, and composite light matrix.
MATRIX rotlgt, rotcube, light;
// Local Light Matrix : Direction and reach of each light source.
// Each light points in the direction aligned with the axis, hence direction is in the same coordinate system as the PSX (see l.23-30 of this file)
// Negative/positive value denotes light direction on corresponding axis
// -4096 > Value < 4096 denotes reach/intensity of light source
MATRIX lgtmat = {
// X Y Z
-ONE, -ONE, ONE, // Lightsource 1 : here, the light source is at the Bottom-Left of the screen, and points into the screen.
0, 0, 0, // Lightsource 2
0, 0, 0, // Lightsource 3
};
// Local Color Matrix
// Set color of each light source (L)
// Value range : 0 > x < 4096
MATRIX cmat = {
// L1 L2 L3
4096, 0, 0, // R
4096, 0, 0, // G
4096, 0, 0 // B
};
// Prototypes
void init(void);
void display(void);
//~ void LoadTexture(u_long * tim, TIM_IMAGE * tparam);
void init(){
// Reset the GPU before doing anything and the controller
PadInit(0);
ResetGraph(0);
// Initialize and setup the GTE
InitGeom();
SetGeomOffset(CENTERX, CENTERY); // x, y offset
SetGeomScreen(CENTERX); // Distance between eye and screen
// Set the display and draw environments
SetDefDispEnv(&disp[0], 0, 0 , SCREENXRES, SCREENYRES);
SetDefDispEnv(&disp[1], 0, SCREENYRES, SCREENXRES, SCREENYRES);
SetDefDrawEnv(&draw[0], 0, SCREENYRES, SCREENXRES, SCREENYRES);
SetDefDrawEnv(&draw[1], 0, 0, SCREENXRES, SCREENYRES);
if (VMODE)
{
SetVideoMode(MODE_PAL);
disp[0].screen.y += 8;
disp[1].screen.y += 8;
}
// Set light env
// Set far color
SetFarColor( BGc.r, BGc.g, BGc.b );
// Set Ambient color
SetBackColor( BKc.vx, BKc.vy, BKc.vz );
// Set Color matrix
SetColorMatrix(&cmat);
// Set Fog settings
SetFogNearFar( 1200, 2200, SCREENXRES );
setRGB0(&draw[0], 0, 0, 255);
setRGB0(&draw[1], 0, 0, 255);
draw[0].isbg = 1;
draw[1].isbg = 1;
PutDispEnv(&disp[db]);
PutDrawEnv(&draw[db]);
// Init font system
FntLoad(960, 0);
FntOpen(16, 16, 196, 64, 0, 256);
}
void display(void){
DrawSync(0);
VSync(0);
PutDispEnv(&disp[db]);
PutDrawEnv(&draw[db]);
SetDispMask(1);
DrawOTag(ot[db] + OTLEN - 1);
db = !db;
nextpri = primbuff[db];
}
int main() {
int i;
int PadStatus;
int TPressed=0;
int AutoRotate=1;
// Rotating cube
POLY_G3 * poly;
SVECTOR Rotate={ ONE/6,ONE/6,ONE/6 }; // Rotation coordinates
VECTOR Trans={ -SCREENXRES/2, 0, CENTERX * 3, 0 }; // Translation coordinates
VECTOR Scale={ ONE/2, ONE/2, ONE/2, 0 }; // Scaling coordinates : ONE == 4096
MATRIX Matrix={0}; // Matrix data for the GTE
// Static cube
POLY_G3 * poly1; // pointer to a POLY_G4
SVECTOR Rotate1={ ONE/6, ONE/6, ONE/6, 0 }; // Rotation coordinates
VECTOR Trans1={ SCREENXRES/2, 0, CENTERX * 3, 0 }; // Translation coordinates
VECTOR Scale1={ ONE/2, ONE/2, ONE/2, 0 }; // Scaling coordinates : ONE == 4096
MATRIX Matrix1={0}; // Matrix data for the GTE
init();
// Main loop
while (1) {
// Read pad status
PadStatus = PadRead(0);
if (AutoRotate == 0) {
if (PadStatus & PADL1) Trans.vz -= 4;
if (PadStatus & PADR1) Trans.vz += 4;
if (PadStatus & PADL2) Rotate.vz -= 8;
if (PadStatus & PADR2) Rotate.vz += 8;
if (PadStatus & PADLup) Rotate.vx -= 8;
if (PadStatus & PADLdown) Rotate.vx += 8;
if (PadStatus & PADLleft) Rotate.vy -= 8;
if (PadStatus & PADLright) Rotate.vy += 8;
if (PadStatus & PADRup) Trans.vy -= 2;
if (PadStatus & PADRdown) Trans.vy += 2;
if (PadStatus & PADRleft) Trans.vx -= 2;
if (PadStatus & PADRright) Trans.vx += 2;
}
if (PadStatus & PADstart) {
if (TPressed == 0) {
AutoRotate = (AutoRotate + 1) & 1;
Rotate.vy = Rotate.vx = Rotate.vz = ONE/6;
Scale.vx = Scale.vy = Scale.vz = ONE/2;
Trans.vx = -SCREENXRES/2;
Trans.vy = 0;
Trans.vz = CENTERX * 3;
}
TPressed = 1;
} else {
TPressed = 0;
}
if (AutoRotate) {
Rotate.vy += 8; // Pan
Rotate.vx += 8; // Tilt
//~ Rotate.vz += 8; // Roll
}
// Clear the current OT
ClearOTagR(ot[db], OTLEN);
// Render the sample vector model
t=0;
// modelCube is a TMESH, len member == # vertices, but here it's # of triangle... So, for each tri * 3 vertices ...
for (i = 0; i < (modelCube.len*3); i += 3) {
poly = (POLY_G3 *)nextpri;
// Initialize the primitive and set its color values
SetPolyG3(poly);
// Rotate, translate, and project the vectors and output the results into a primitive
// Could be replaced with one call with RotTransPers3()
OTz = RotTransPers(&modelCube_mesh[modelCube_index[t]] , (long*)&poly->x0, &p, &Flag);
OTz += RotTransPers(&modelCube_mesh[modelCube_index[t+2]], (long*)&poly->x1, &p, &Flag);
OTz += RotTransPers(&modelCube_mesh[modelCube_index[t+1]], (long*)&poly->x2, &p, &Flag);
// Find light color
// Work color vectors
CVECTOR outCol, outCol1, outCol2 = { 0,0,0,0 };
// Find local color from three normal vectors and perform depth cueing.
// Could be replaced with one call with NormalColorDpq3()
NormalColorDpq(&modelCube.n[ modelCube_index[t+0] ], &modelCube.c[i+0], p, &outCol);
NormalColorDpq(&modelCube.n[ modelCube_index[t+2] ], &modelCube.c[i+2], p, &outCol1);
NormalColorDpq(&modelCube.n[ modelCube_index[t+1] ], &modelCube.c[i+1], p, &outCol2);
// Set vertex colors
setRGB0(poly, outCol.r, outCol.g , outCol.b);
setRGB1(poly, outCol1.r, outCol1.g, outCol1.b);
setRGB2(poly, outCol2.r, outCol2.g, outCol2.b);
// Sort the primitive into the OT
OTz /= 3;
if ((OTz > 0) && (OTz < OTLEN))
AddPrim(&ot[db][OTz-2], poly);
nextpri += sizeof(POLY_G3);
t+=3;
}
// Find and apply light rotation matrix
//~ // Find rotmat from light angles
RotMatrix_gte(&lgtang, &rotlgt);
// Find rotmat from cube angles
RotMatrix_gte(&Rotate, &rotcube);
// RotMatrix cube * RotMatrix light
MulMatrix0(&rotcube, &rotlgt, &rotlgt);
// Light Matrix * RotMatrix light
MulMatrix0(&lgtmat, &rotlgt, &light);
// Set new light matrix
SetLightMatrix(&light);
// Convert and set the matrices
// Find Rotation matrix from object's angles
RotMatrix(&Rotate, &Matrix);
// Find Scale matrix from object's angles
ScaleMatrix(&Matrix, &Scale);
// Find Translation matrix from object's angles
TransMatrix(&Matrix, &Trans);
// Set GTE's rotation matrix
SetRotMatrix(&Matrix);
// Set GTE's Translation matrix
SetTransMatrix(&Matrix);
// Draw static cube
t=0;
for (i = 0; i < (modelCube1.len*3); i += 3) {
poly1 = (POLY_G3 *)nextpri;
SetPolyG3(poly1);
OTz = RotTransPers(&modelCube1_mesh[modelCube1_index[t]] , (long*)&poly1->x0, &p, &Flag);
OTz += RotTransPers(&modelCube1_mesh[modelCube1_index[t+2]], (long*)&poly1->x1, &p, &Flag);
OTz += RotTransPers(&modelCube1_mesh[modelCube1_index[t+1]], (long*)&poly1->x2, &p, &Flag);
CVECTOR outCol = { 0,0,0,0 };
CVECTOR outCol1 = { 0,0,0,0 };
CVECTOR outCol2 = { 0,0,0,0 };
NormalColorDpq(&modelCube1.n[ modelCube1_index[t+0] ], &modelCube1.c[i+0], p, &outCol);
NormalColorDpq(&modelCube1.n[ modelCube1_index[t+2] ], &modelCube1.c[i+2], p, &outCol1);
NormalColorDpq(&modelCube1.n[ modelCube1_index[t+1] ], &modelCube1.c[i+1], p, &outCol2);
setRGB0(poly1, outCol.r, outCol.g , outCol.b);
setRGB1(poly1, outCol1.r, outCol1.g, outCol1.b);
setRGB2(poly1, outCol2.r, outCol2.g, outCol2.b);
OTz /= 3;
if ((OTz > 0) && (OTz < OTLEN))
AddPrim(&ot[db][OTz-2], poly1);
nextpri += sizeof(POLY_G3);
t+=3;
}
// See l.216
RotMatrix_gte(&lgtang, &rotlgt);
RotMatrix_gte(&Rotate1, &rotcube);
MulMatrix0(&rotcube, &rotlgt, &rotlgt);
MulMatrix0(&lgtmat, &rotlgt, &light);
SetLightMatrix(&light);
// See l.227
RotMatrix(&Rotate1, &Matrix1);
ScaleMatrix(&Matrix1, &Scale1);
TransMatrix(&Matrix1, &Trans1);
SetRotMatrix(&Matrix1);
SetTransMatrix(&Matrix1);
FntPrint("Hello lightsources !\n");
FntFlush(-1);
display();
}
return 0;
}